zig/src/codegen/c.zig
2022-10-12 12:40:59 +03:00

4339 lines
158 KiB
Zig

const std = @import("std");
const builtin = @import("builtin");
const assert = std.debug.assert;
const mem = std.mem;
const log = std.log.scoped(.c);
const link = @import("../link.zig");
const Module = @import("../Module.zig");
const Compilation = @import("../Compilation.zig");
const Value = @import("../value.zig").Value;
const Type = @import("../type.zig").Type;
const TypedValue = @import("../TypedValue.zig");
const C = link.File.C;
const Decl = Module.Decl;
const trace = @import("../tracy.zig").trace;
const LazySrcLoc = Module.LazySrcLoc;
const Air = @import("../Air.zig");
const Liveness = @import("../Liveness.zig");
const CType = @import("../type.zig").CType;
const Mutability = enum { Const, Mut };
const BigIntConst = std.math.big.int.Const;
pub const CValue = union(enum) {
none: void,
/// Index into local_names
local: usize,
/// Index into local_names, but take the address.
local_ref: usize,
/// A constant instruction, to be rendered inline.
constant: Air.Inst.Ref,
/// Index into the parameters
arg: usize,
/// By-value
decl: Decl.Index,
decl_ref: Decl.Index,
/// An undefined (void *) pointer (cannot be dereferenced)
undefined_ptr: void,
/// Render the slice as an identifier (using fmtIdent)
identifier: []const u8,
/// Render these bytes literally.
/// TODO make this a [*:0]const u8 to save memory
bytes: []const u8,
};
const BlockData = struct {
block_id: usize,
result: CValue,
};
pub const CValueMap = std.AutoHashMap(Air.Inst.Ref, CValue);
pub const TypedefMap = std.ArrayHashMap(
Type,
struct { name: []const u8, rendered: []u8 },
Type.HashContext32,
true,
);
const FormatTypeAsCIdentContext = struct {
ty: Type,
mod: *Module,
};
const ValueRenderLocation = enum {
FunctionArgument,
Other,
};
/// TODO make this not cut off at 128 bytes
fn formatTypeAsCIdentifier(
data: FormatTypeAsCIdentContext,
comptime fmt: []const u8,
options: std.fmt.FormatOptions,
writer: anytype,
) !void {
_ = fmt;
_ = options;
var buffer = [1]u8{0} ** 128;
var buf = std.fmt.bufPrint(&buffer, "{}", .{data.ty.fmt(data.mod)}) catch &buffer;
return formatIdent(buf, "", .{}, writer);
}
pub fn typeToCIdentifier(ty: Type, mod: *Module) std.fmt.Formatter(formatTypeAsCIdentifier) {
return .{ .data = .{
.ty = ty,
.mod = mod,
} };
}
const reserved_idents = std.ComptimeStringMap(void, .{
.{ "_Alignas", {
@setEvalBranchQuota(4000);
} },
.{ "_Alignof", {} },
.{ "_Atomic", {} },
.{ "_Bool", {} },
.{ "_Complex", {} },
.{ "_Decimal128", {} },
.{ "_Decimal32", {} },
.{ "_Decimal64", {} },
.{ "_Generic", {} },
.{ "_Imaginary", {} },
.{ "_Noreturn", {} },
.{ "_Pragma", {} },
.{ "_Static_assert", {} },
.{ "_Thread_local", {} },
.{ "alignas", {} },
.{ "alignof", {} },
.{ "asm", {} },
.{ "atomic_bool", {} },
.{ "atomic_char", {} },
.{ "atomic_char16_t", {} },
.{ "atomic_char32_t", {} },
.{ "atomic_int", {} },
.{ "atomic_int_fast16_t", {} },
.{ "atomic_int_fast32_t", {} },
.{ "atomic_int_fast64_t", {} },
.{ "atomic_int_fast8_t", {} },
.{ "atomic_int_least16_t", {} },
.{ "atomic_int_least32_t", {} },
.{ "atomic_int_least64_t", {} },
.{ "atomic_int_least8_t", {} },
.{ "atomic_intmax_t", {} },
.{ "atomic_intptr_t", {} },
.{ "atomic_llong", {} },
.{ "atomic_long", {} },
.{ "atomic_ptrdiff_t", {} },
.{ "atomic_schar", {} },
.{ "atomic_short", {} },
.{ "atomic_size_t", {} },
.{ "atomic_uchar", {} },
.{ "atomic_uint", {} },
.{ "atomic_uint_fast16_t", {} },
.{ "atomic_uint_fast32_t", {} },
.{ "atomic_uint_fast64_t", {} },
.{ "atomic_uint_fast8_t", {} },
.{ "atomic_uint_least16_t", {} },
.{ "atomic_uint_least32_t", {} },
.{ "atomic_uint_least64_t", {} },
.{ "atomic_uint_least8_t", {} },
.{ "atomic_uintmax_t", {} },
.{ "atomic_uintptr_t", {} },
.{ "atomic_ullong", {} },
.{ "atomic_ulong", {} },
.{ "atomic_ushort", {} },
.{ "atomic_wchar_t", {} },
.{ "auto", {} },
.{ "bool", {} },
.{ "break", {} },
.{ "case", {} },
.{ "char", {} },
.{ "complex", {} },
.{ "const", {} },
.{ "continue", {} },
.{ "default", {} },
.{ "do", {} },
.{ "double", {} },
.{ "else", {} },
.{ "enum", {} },
.{ "extern ", {} },
.{ "float", {} },
.{ "for", {} },
.{ "fortran", {} },
.{ "goto", {} },
.{ "if", {} },
.{ "imaginary", {} },
.{ "inline", {} },
.{ "int", {} },
.{ "int16_t", {} },
.{ "int32_t", {} },
.{ "int64_t", {} },
.{ "int8_t", {} },
.{ "intptr_t", {} },
.{ "long", {} },
.{ "noreturn", {} },
.{ "register", {} },
.{ "restrict", {} },
.{ "return", {} },
.{ "short ", {} },
.{ "signed", {} },
.{ "size_t", {} },
.{ "sizeof", {} },
.{ "ssize_t", {} },
.{ "static", {} },
.{ "static_assert", {} },
.{ "struct", {} },
.{ "switch", {} },
.{ "thread_local", {} },
.{ "typedef", {} },
.{ "uint16_t", {} },
.{ "uint32_t", {} },
.{ "uint64_t", {} },
.{ "uint8_t", {} },
.{ "uintptr_t", {} },
.{ "union", {} },
.{ "unsigned", {} },
.{ "void", {} },
.{ "volatile", {} },
.{ "while ", {} },
});
fn formatIdent(
ident: []const u8,
comptime fmt: []const u8,
options: std.fmt.FormatOptions,
writer: anytype,
) !void {
_ = options;
const solo = fmt.len != 0 and fmt[0] == ' '; // space means solo; not part of a bigger ident.
if (solo and reserved_idents.has(ident)) {
try writer.writeAll("zig_e_");
}
for (ident) |c, i| {
switch (c) {
'a'...'z', 'A'...'Z', '_' => try writer.writeByte(c),
'.' => try writer.writeByte('_'),
'0'...'9' => if (i == 0) {
try writer.print("_{x:2}", .{c});
} else {
try writer.writeByte(c);
},
else => try writer.print("_{x:2}", .{c}),
}
}
}
pub fn fmtIdent(ident: []const u8) std.fmt.Formatter(formatIdent) {
return .{ .data = ident };
}
/// This data is available when outputting .c code for a `*Module.Fn`.
/// It is not available when generating .h file.
pub const Function = struct {
air: Air,
liveness: Liveness,
value_map: CValueMap,
blocks: std.AutoHashMapUnmanaged(Air.Inst.Index, BlockData) = .{},
next_arg_index: usize = 0,
next_local_index: usize = 0,
next_block_index: usize = 0,
object: Object,
func: *Module.Fn,
fn resolveInst(f: *Function, inst: Air.Inst.Ref) !CValue {
const gop = try f.value_map.getOrPut(inst);
if (gop.found_existing) return gop.value_ptr.*;
const val = f.air.value(inst).?;
const ty = f.air.typeOf(inst);
switch (ty.zigTypeTag()) {
.Array => {
const writer = f.object.code_header.writer();
const decl_c_value = f.allocLocalValue();
gop.value_ptr.* = decl_c_value;
try writer.writeAll("static ");
try f.object.dg.renderTypeAndName(
writer,
ty,
decl_c_value,
.Const,
0,
);
try writer.writeAll(" = ");
try f.object.dg.renderValue(writer, ty, val, .Other);
try writer.writeAll(";\n ");
return decl_c_value;
},
else => {
const result = CValue{ .constant = inst };
gop.value_ptr.* = result;
return result;
},
}
}
fn allocLocalValue(f: *Function) CValue {
const result = f.next_local_index;
f.next_local_index += 1;
return .{ .local = result };
}
fn allocLocal(f: *Function, ty: Type, mutability: Mutability) !CValue {
return f.allocAlignedLocal(ty, mutability, 0);
}
fn allocAlignedLocal(f: *Function, ty: Type, mutability: Mutability, alignment: u32) !CValue {
const local_value = f.allocLocalValue();
try f.object.dg.renderTypeAndName(
f.object.writer(),
ty,
local_value,
mutability,
alignment,
);
return local_value;
}
fn writeCValue(f: *Function, w: anytype, c_value: CValue) !void {
switch (c_value) {
.constant => |inst| {
const ty = f.air.typeOf(inst);
const val = f.air.value(inst).?;
return f.object.dg.renderValue(w, ty, val, .Other);
},
else => return f.object.dg.writeCValue(w, c_value),
}
}
fn writeCValueDeref(f: *Function, w: anytype, c_value: CValue) !void {
switch (c_value) {
.constant => |inst| {
const ty = f.air.typeOf(inst);
const val = f.air.value(inst).?;
try w.writeAll("(*");
try f.object.dg.renderValue(w, ty, val, .Other);
return w.writeByte(')');
},
else => return f.object.dg.writeCValueDeref(w, c_value),
}
}
fn fail(f: *Function, comptime format: []const u8, args: anytype) error{ AnalysisFail, OutOfMemory } {
return f.object.dg.fail(format, args);
}
fn renderType(f: *Function, w: anytype, t: Type) !void {
return f.object.dg.renderType(w, t);
}
fn renderTypecast(f: *Function, w: anytype, t: Type) !void {
return f.object.dg.renderTypecast(w, t);
}
};
/// This data is available when outputting .c code for a `Module`.
/// It is not available when generating .h file.
pub const Object = struct {
dg: DeclGen,
code: std.ArrayList(u8),
/// Goes before code. Initialized and deinitialized in `genFunc`.
code_header: std.ArrayList(u8) = undefined,
indent_writer: IndentWriter(std.ArrayList(u8).Writer),
fn writer(o: *Object) IndentWriter(std.ArrayList(u8).Writer).Writer {
return o.indent_writer.writer();
}
};
/// This data is available both when outputting .c code and when outputting an .h file.
pub const DeclGen = struct {
gpa: std.mem.Allocator,
module: *Module,
decl: *Decl,
decl_index: Decl.Index,
fwd_decl: std.ArrayList(u8),
error_msg: ?*Module.ErrorMsg,
/// The key of this map is Type which has references to typedefs_arena.
typedefs: TypedefMap,
typedefs_arena: std.mem.Allocator,
fn fail(dg: *DeclGen, comptime format: []const u8, args: anytype) error{ AnalysisFail, OutOfMemory } {
@setCold(true);
const src = LazySrcLoc.nodeOffset(0);
const src_loc = src.toSrcLoc(dg.decl);
dg.error_msg = try Module.ErrorMsg.create(dg.module.gpa, src_loc, format, args);
return error.AnalysisFail;
}
fn getTypedefName(dg: *DeclGen, t: Type) ?[]const u8 {
if (dg.typedefs.get(t)) |some| {
return some.name;
} else {
return null;
}
}
fn renderDeclValue(
dg: *DeclGen,
writer: anytype,
ty: Type,
val: Value,
decl_index: Decl.Index,
) error{ OutOfMemory, AnalysisFail }!void {
if (ty.isSlice()) {
try writer.writeByte('(');
try dg.renderTypecast(writer, ty);
try writer.writeAll("){");
var buf: Type.SlicePtrFieldTypeBuffer = undefined;
try dg.renderValue(writer, ty.slicePtrFieldType(&buf), val.slicePtr(), .Other);
try writer.writeAll(", ");
try writer.print("{d}", .{val.sliceLen(dg.module)});
try writer.writeAll("}");
return;
}
const decl = dg.module.declPtr(decl_index);
assert(decl.has_tv);
// We shouldn't cast C function pointers as this is UB (when you call
// them). The analysis until now should ensure that the C function
// pointers are compatible. If they are not, then there is a bug
// somewhere and we should let the C compiler tell us about it.
if (ty.castPtrToFn() == null) {
// Determine if we must pointer cast.
if (ty.eql(decl.ty, dg.module)) {
try writer.writeByte('&');
try dg.renderDeclName(writer, decl_index);
return;
}
try writer.writeAll("((");
try dg.renderTypecast(writer, ty);
try writer.writeAll(")&");
try dg.renderDeclName(writer, decl_index);
try writer.writeByte(')');
return;
}
try dg.renderDeclName(writer, decl_index);
}
fn renderInt128(
writer: anytype,
int_val: anytype,
) error{ OutOfMemory, AnalysisFail }!void {
const int_info = @typeInfo(@TypeOf(int_val)).Int;
const is_signed = int_info.signedness == .signed;
const is_neg = int_val < 0;
comptime assert(int_info.bits > 64 and int_info.bits <= 128);
// Clang and GCC don't support 128-bit integer constants but will hopefully unfold them
// if we construct one manually.
const magnitude = std.math.absCast(int_val);
const high = @truncate(u64, magnitude >> 64);
const low = @truncate(u64, magnitude);
// (int128_t)/<->( ( (uint128_t)( val_high << 64 )u ) + (uint128_t)val_low/u )
if (is_signed) try writer.writeAll("(int128_t)");
if (is_neg) try writer.writeByte('-');
try writer.print("(((uint128_t)0x{x}u<<64)", .{high});
if (low > 0)
try writer.print("+(uint128_t)0x{x}u", .{low});
return writer.writeByte(')');
}
fn renderBigIntConst(
dg: *DeclGen,
writer: anytype,
val: BigIntConst,
signed: bool,
) error{ OutOfMemory, AnalysisFail }!void {
if (signed) {
try renderInt128(writer, val.to(i128) catch {
return dg.fail("TODO implement integer constants larger than 128 bits", .{});
});
} else {
try renderInt128(writer, val.to(u128) catch {
return dg.fail("TODO implement integer constants larger than 128 bits", .{});
});
}
}
// Renders a "parent" pointer by recursing to the root decl/variable
// that its contents are defined with respect to.
//
// Used for .elem_ptr, .field_ptr, .opt_payload_ptr, .eu_payload_ptr
fn renderParentPtr(dg: *DeclGen, writer: anytype, ptr_val: Value, ptr_ty: Type) error{ OutOfMemory, AnalysisFail }!void {
try writer.writeByte('(');
try dg.renderTypecast(writer, ptr_ty);
try writer.writeByte(')');
switch (ptr_val.tag()) {
.decl_ref_mut, .decl_ref, .variable => {
const decl_index = switch (ptr_val.tag()) {
.decl_ref => ptr_val.castTag(.decl_ref).?.data,
.decl_ref_mut => ptr_val.castTag(.decl_ref_mut).?.data.decl_index,
.variable => ptr_val.castTag(.variable).?.data.owner_decl,
else => unreachable,
};
try dg.renderDeclValue(writer, ptr_ty, ptr_val, decl_index);
},
.field_ptr => {
const field_ptr = ptr_val.castTag(.field_ptr).?.data;
const container_ty = field_ptr.container_ty;
const index = field_ptr.field_index;
const FieldInfo = struct { name: []const u8, ty: Type };
const field_info: FieldInfo = switch (container_ty.zigTypeTag()) {
.Struct => .{
.name = container_ty.structFields().keys()[index],
.ty = container_ty.structFields().values()[index].ty,
},
.Union => .{
.name = container_ty.unionFields().keys()[index],
.ty = container_ty.unionFields().values()[index].ty,
},
.Pointer => switch (container_ty.ptrSize()) {
.Slice => switch (index) {
0 => FieldInfo{ .name = "ptr", .ty = container_ty.childType() },
1 => FieldInfo{ .name = "len", .ty = Type.usize },
else => unreachable,
},
else => unreachable,
},
else => unreachable,
};
var container_ptr_ty_pl: Type.Payload.ElemType = .{
.base = .{ .tag = .c_mut_pointer },
.data = field_ptr.container_ty,
};
const container_ptr_ty = Type.initPayload(&container_ptr_ty_pl.base);
if (field_info.ty.hasRuntimeBitsIgnoreComptime()) {
try writer.writeAll("&(");
try dg.renderParentPtr(writer, field_ptr.container_ptr, container_ptr_ty);
if (field_ptr.container_ty.tag() == .union_tagged or field_ptr.container_ty.tag() == .union_safety_tagged) {
try writer.print(")->payload.{ }", .{fmtIdent(field_info.name)});
} else {
try writer.print(")->{ }", .{fmtIdent(field_info.name)});
}
} else {
try dg.renderParentPtr(writer, field_ptr.container_ptr, field_info.ty);
}
},
.elem_ptr => {
const elem_ptr = ptr_val.castTag(.elem_ptr).?.data;
var elem_ptr_ty_pl: Type.Payload.ElemType = .{
.base = .{ .tag = .c_mut_pointer },
.data = elem_ptr.elem_ty,
};
const elem_ptr_ty = Type.initPayload(&elem_ptr_ty_pl.base);
try writer.writeAll("&(");
try dg.renderParentPtr(writer, elem_ptr.array_ptr, elem_ptr_ty);
try writer.print(")[{d}]", .{elem_ptr.index});
},
.opt_payload_ptr, .eu_payload_ptr => {
const payload_ptr = ptr_val.cast(Value.Payload.PayloadPtr).?.data;
var container_ptr_ty_pl: Type.Payload.ElemType = .{
.base = .{ .tag = .c_mut_pointer },
.data = payload_ptr.container_ty,
};
const container_ptr_ty = Type.initPayload(&container_ptr_ty_pl.base);
try writer.writeAll("&(");
try dg.renderParentPtr(writer, payload_ptr.container_ptr, container_ptr_ty);
try writer.writeAll(")->payload");
},
else => unreachable,
}
}
fn renderValue(
dg: *DeclGen,
writer: anytype,
ty: Type,
val: Value,
location: ValueRenderLocation,
) error{ OutOfMemory, AnalysisFail }!void {
const target = dg.module.getTarget();
if (val.isUndefDeep()) {
switch (ty.zigTypeTag()) {
// Using '{}' for integer and floats seemed to error C compilers (both GCC and Clang)
// with 'error: expected expression' (including when built with 'zig cc')
.Int => {
const c_bits = toCIntBits(ty.intInfo(dg.module.getTarget()).bits) orelse
return dg.fail("TODO: C backend: implement integer types larger than 128 bits", .{});
switch (c_bits) {
8 => return writer.writeAll("0xaau"),
16 => return writer.writeAll("0xaaaau"),
32 => return writer.writeAll("0xaaaaaaaau"),
64 => return writer.writeAll("0xaaaaaaaaaaaaaaaau"),
128 => return renderInt128(writer, @as(u128, 0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa)),
else => unreachable,
}
},
.Float => {
switch (ty.floatBits(dg.module.getTarget())) {
32 => return writer.writeAll("zig_bitcast_f32_u32(0xaaaaaaaau)"),
64 => return writer.writeAll("zig_bitcast_f64_u64(0xaaaaaaaaaaaaaaaau)"),
else => return dg.fail("TODO float types > 64 bits are not support in renderValue() as of now", .{}),
}
},
.Pointer => switch (dg.module.getTarget().cpu.arch.ptrBitWidth()) {
32 => return writer.writeAll("(void *)0xaaaaaaaa"),
64 => return writer.writeAll("(void *)0xaaaaaaaaaaaaaaaa"),
else => unreachable,
},
.Struct, .ErrorUnion => {
try writer.writeByte('(');
try dg.renderTypecast(writer, ty);
return writer.writeAll("){0xaa}");
},
else => {
// This should lower to 0xaa bytes in safe modes, and for unsafe modes should
// lower to leaving variables uninitialized (that might need to be implemented
// outside of this function).
return writer.writeAll("{}");
},
}
}
switch (ty.zigTypeTag()) {
.Int => switch (val.tag()) {
.int_big_positive => try dg.renderBigIntConst(writer, val.castTag(.int_big_positive).?.asBigInt(), ty.isSignedInt()),
.int_big_negative => try dg.renderBigIntConst(writer, val.castTag(.int_big_negative).?.asBigInt(), true),
.field_ptr,
.elem_ptr,
.opt_payload_ptr,
.eu_payload_ptr,
.decl_ref_mut,
.decl_ref,
=> try dg.renderParentPtr(writer, val, ty),
else => {
if (ty.isSignedInt())
return writer.print("{d}", .{val.toSignedInt()});
return writer.print("{d}u", .{val.toUnsignedInt(target)});
},
},
.Float => {
if (ty.floatBits(dg.module.getTarget()) <= 64) {
if (std.math.isNan(val.toFloat(f64)) or std.math.isInf(val.toFloat(f64))) {
// just generate a bit cast (exactly like we do in airBitcast)
switch (ty.tag()) {
.f32 => return writer.print("zig_bitcast_f32_u32(0x{x})", .{@bitCast(u32, val.toFloat(f32))}),
.f64 => return writer.print("zig_bitcast_f64_u64(0x{x})", .{@bitCast(u64, val.toFloat(f64))}),
else => return dg.fail("TODO float types > 64 bits are not support in renderValue() as of now", .{}),
}
} else {
return writer.print("{x}", .{val.toFloat(f64)});
}
}
return dg.fail("TODO: C backend: implement lowering large float values", .{});
},
.Pointer => switch (val.tag()) {
.null_value => try writer.writeAll("NULL"),
// Technically this should produce NULL but the integer literal 0 will always coerce
// to the assigned pointer type. Note this is just a hack to fix warnings from ordered comparisons (<, >, etc)
// between pointers and 0, which is an extension to begin with.
.zero => try writer.writeByte('0'),
.variable => {
const decl = val.castTag(.variable).?.data.owner_decl;
return dg.renderDeclValue(writer, ty, val, decl);
},
.slice => {
const slice = val.castTag(.slice).?.data;
var buf: Type.SlicePtrFieldTypeBuffer = undefined;
try writer.writeByte('(');
try dg.renderTypecast(writer, ty);
try writer.writeAll("){");
try dg.renderValue(writer, ty.slicePtrFieldType(&buf), slice.ptr, location);
try writer.writeAll(", ");
try dg.renderValue(writer, Type.usize, slice.len, location);
try writer.writeAll("}");
},
.function => {
const func = val.castTag(.function).?.data;
try dg.renderDeclName(writer, func.owner_decl);
},
.extern_fn => {
const extern_fn = val.castTag(.extern_fn).?.data;
try dg.renderDeclName(writer, extern_fn.owner_decl);
},
.int_u64, .one => {
try writer.writeAll("((");
try dg.renderTypecast(writer, ty);
try writer.print(")0x{x}u)", .{val.toUnsignedInt(target)});
},
.field_ptr,
.elem_ptr,
.opt_payload_ptr,
.eu_payload_ptr,
.decl_ref_mut,
.decl_ref,
=> try dg.renderParentPtr(writer, val, ty),
else => unreachable,
},
.Array => {
// First try specific tag representations for more efficiency.
switch (val.tag()) {
.undef, .empty_struct_value, .empty_array => {
try writer.writeByte('{');
const ai = ty.arrayInfo();
if (ai.sentinel) |s| {
try dg.renderValue(writer, ai.elem_type, s, location);
}
try writer.writeByte('}');
},
else => {
// Fall back to generic implementation.
var arena = std.heap.ArenaAllocator.init(dg.module.gpa);
defer arena.deinit();
const arena_allocator = arena.allocator();
if (location == .FunctionArgument) {
try writer.writeByte('(');
try dg.renderTypecast(writer, ty);
try writer.writeByte(')');
}
try writer.writeByte('{');
const ai = ty.arrayInfo();
var index: usize = 0;
while (index < ai.len) : (index += 1) {
if (index != 0) try writer.writeAll(",");
const elem_val = try val.elemValue(dg.module, arena_allocator, index);
try dg.renderValue(writer, ai.elem_type, elem_val, .Other);
}
if (ai.sentinel) |s| {
if (index != 0) try writer.writeAll(",");
try dg.renderValue(writer, ai.elem_type, s, .Other);
}
try writer.writeByte('}');
},
}
},
.Bool => return writer.print("{}", .{val.toBool()}),
.Optional => {
var opt_buf: Type.Payload.ElemType = undefined;
const payload_ty = ty.optionalChild(&opt_buf);
if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
const is_null = val.castTag(.opt_payload) == null;
return writer.print("{}", .{is_null});
}
if (ty.optionalReprIsPayload()) {
return dg.renderValue(writer, payload_ty, val, location);
}
try writer.writeByte('(');
try dg.renderTypecast(writer, ty);
try writer.writeAll("){");
if (val.castTag(.opt_payload)) |pl| {
const payload_val = pl.data;
try writer.writeAll(" .is_null = false, .payload = ");
try dg.renderValue(writer, payload_ty, payload_val, location);
try writer.writeAll(" }");
} else {
try writer.writeAll(" .is_null = true }");
}
},
.ErrorSet => {
switch (val.tag()) {
.@"error" => {
const payload = val.castTag(.@"error").?;
// error values will be #defined at the top of the file
return writer.print("zig_error_{s}", .{payload.data.name});
},
else => {
// In this case we are rendering an error union which has a
// 0 bits payload.
return writer.writeAll("0");
},
}
},
.ErrorUnion => {
const error_type = ty.errorUnionSet();
const payload_type = ty.errorUnionPayload();
if (!payload_type.hasRuntimeBits()) {
// We use the error type directly as the type.
const err_val = if (val.errorUnionIsPayload()) Value.initTag(.zero) else val;
return dg.renderValue(writer, error_type, err_val, location);
}
try writer.writeByte('(');
try dg.renderTypecast(writer, ty);
try writer.writeAll("){");
if (val.castTag(.eu_payload)) |pl| {
const payload_val = pl.data;
try writer.writeAll(" .payload = ");
try dg.renderValue(writer, payload_type, payload_val, location);
try writer.writeAll(", .error = 0 }");
} else {
try writer.writeAll(" .error = ");
try dg.renderValue(writer, error_type, val, location);
try writer.writeAll(" }");
}
},
.Enum => {
switch (val.tag()) {
.enum_field_index => {
const field_index = val.castTag(.enum_field_index).?.data;
switch (ty.tag()) {
.enum_simple => return writer.print("{d}", .{field_index}),
.enum_full, .enum_nonexhaustive => {
const enum_full = ty.cast(Type.Payload.EnumFull).?.data;
if (enum_full.values.count() != 0) {
const tag_val = enum_full.values.keys()[field_index];
return dg.renderValue(writer, enum_full.tag_ty, tag_val, location);
} else {
return writer.print("{d}", .{field_index});
}
},
.enum_numbered => {
const enum_obj = ty.castTag(.enum_numbered).?.data;
if (enum_obj.values.count() != 0) {
const tag_val = enum_obj.values.keys()[field_index];
return dg.renderValue(writer, enum_obj.tag_ty, tag_val, location);
} else {
return writer.print("{d}", .{field_index});
}
},
else => unreachable,
}
},
else => {
var int_tag_ty_buffer: Type.Payload.Bits = undefined;
const int_tag_ty = ty.intTagType(&int_tag_ty_buffer);
return dg.renderValue(writer, int_tag_ty, val, location);
},
}
},
.Fn => switch (val.tag()) {
.function => {
const decl = val.castTag(.function).?.data.owner_decl;
return dg.renderDeclValue(writer, ty, val, decl);
},
.extern_fn => {
const decl = val.castTag(.extern_fn).?.data.owner_decl;
return dg.renderDeclValue(writer, ty, val, decl);
},
else => unreachable,
},
.Struct => {
const field_vals = val.castTag(.aggregate).?.data;
try writer.writeAll("(");
try dg.renderTypecast(writer, ty);
try writer.writeAll("){");
var i: usize = 0;
for (field_vals) |field_val, field_index| {
const field_ty = ty.structFieldType(field_index);
if (!field_ty.hasRuntimeBits()) continue;
if (i != 0) try writer.writeAll(",");
try dg.renderValue(writer, field_ty, field_val, location);
i += 1;
}
try writer.writeAll("}");
},
.Union => {
const union_obj = val.castTag(.@"union").?.data;
const layout = ty.unionGetLayout(target);
try writer.writeAll("(");
try dg.renderTypecast(writer, ty);
try writer.writeAll("){");
if (ty.unionTagTypeSafety()) |tag_ty| {
if (layout.tag_size != 0) {
try writer.writeAll(".tag = ");
try dg.renderValue(writer, tag_ty, union_obj.tag, location);
try writer.writeAll(", ");
}
try writer.writeAll(".payload = {");
}
const index = ty.unionTagFieldIndex(union_obj.tag, dg.module).?;
const field_ty = ty.unionFields().values()[index].ty;
const field_name = ty.unionFields().keys()[index];
if (field_ty.hasRuntimeBits()) {
try writer.print(".{ } = ", .{fmtIdent(field_name)});
try dg.renderValue(writer, field_ty, union_obj.val, location);
}
if (ty.unionTagTypeSafety()) |_| {
try writer.writeAll("}");
}
try writer.writeAll("}");
},
.ComptimeInt => unreachable,
.ComptimeFloat => unreachable,
.Type => unreachable,
.EnumLiteral => unreachable,
.Void => unreachable,
.NoReturn => unreachable,
.Undefined => unreachable,
.Null => unreachable,
.BoundFn => unreachable,
.Opaque => unreachable,
.Frame,
.AnyFrame,
.Vector,
=> |tag| return dg.fail("TODO: C backend: implement value of type {s}", .{
@tagName(tag),
}),
}
}
fn renderFunctionSignature(dg: *DeclGen, w: anytype, is_global: bool) !void {
if (!is_global) {
try w.writeAll("static ");
}
if (dg.decl.val.castTag(.function)) |func_payload| {
const func: *Module.Fn = func_payload.data;
if (func.is_cold) {
try w.writeAll("ZIG_COLD ");
}
}
const fn_info = dg.decl.ty.fnInfo();
if (fn_info.return_type.hasRuntimeBits()) {
try dg.renderType(w, fn_info.return_type);
} else if (fn_info.return_type.isError()) {
try dg.renderType(w, Type.anyerror);
} else if (fn_info.return_type.zigTypeTag() == .NoReturn) {
try w.writeAll("zig_noreturn void");
} else {
try w.writeAll("void");
}
try w.writeAll(" ");
try dg.renderDeclName(w, dg.decl_index);
try w.writeAll("(");
var params_written: usize = 0;
for (fn_info.param_types) |param_type, index| {
if (!param_type.hasRuntimeBitsIgnoreComptime()) continue;
if (params_written > 0) {
try w.writeAll(", ");
}
const name = CValue{ .arg = index };
try dg.renderTypeAndName(w, param_type, name, .Mut, 0);
params_written += 1;
}
if (fn_info.is_var_args) {
if (params_written != 0) try w.writeAll(", ");
try w.writeAll("...");
} else if (params_written == 0) {
try w.writeAll("void");
}
try w.writeByte(')');
}
fn renderPtrToFnTypedef(dg: *DeclGen, t: Type, fn_ty: Type) error{ OutOfMemory, AnalysisFail }![]const u8 {
var buffer = std.ArrayList(u8).init(dg.typedefs.allocator);
defer buffer.deinit();
const bw = buffer.writer();
const fn_info = fn_ty.fnInfo();
try bw.writeAll("typedef ");
try dg.renderType(bw, fn_info.return_type);
try bw.writeAll(" (*");
const name_start = buffer.items.len;
try bw.print("zig_F_{s})(", .{typeToCIdentifier(t, dg.module)});
const name_end = buffer.items.len - 2;
const param_len = fn_info.param_types.len;
var params_written: usize = 0;
var index: usize = 0;
while (index < param_len) : (index += 1) {
if (!fn_info.param_types[index].hasRuntimeBitsIgnoreComptime()) continue;
if (params_written > 0) {
try bw.writeAll(", ");
}
try dg.renderTypecast(bw, fn_info.param_types[index]);
params_written += 1;
}
if (fn_info.is_var_args) {
if (params_written != 0) try bw.writeAll(", ");
try bw.writeAll("...");
} else if (params_written == 0) {
try bw.writeAll("void");
}
try bw.writeAll(");\n");
const rendered = buffer.toOwnedSlice();
errdefer dg.typedefs.allocator.free(rendered);
const name = rendered[name_start..name_end];
try dg.typedefs.ensureUnusedCapacity(1);
dg.typedefs.putAssumeCapacityNoClobber(
try t.copy(dg.typedefs_arena),
.{ .name = name, .rendered = rendered },
);
return name;
}
fn renderSliceTypedef(dg: *DeclGen, t: Type) error{ OutOfMemory, AnalysisFail }![]const u8 {
var buffer = std.ArrayList(u8).init(dg.typedefs.allocator);
defer buffer.deinit();
const bw = buffer.writer();
try bw.writeAll("typedef struct { ");
var ptr_type_buf: Type.SlicePtrFieldTypeBuffer = undefined;
const ptr_type = t.slicePtrFieldType(&ptr_type_buf);
const ptr_name = CValue{ .bytes = "ptr" };
try dg.renderTypeAndName(bw, ptr_type, ptr_name, .Mut, 0);
const ptr_sentinel = ptr_type.ptrInfo().data.sentinel;
const child_type = t.childType();
try bw.writeAll("; size_t len; } ");
const name_index = buffer.items.len;
if (t.isConstPtr()) {
try bw.print("zig_L_{s}", .{typeToCIdentifier(child_type, dg.module)});
} else {
try bw.print("zig_M_{s}", .{typeToCIdentifier(child_type, dg.module)});
}
if (ptr_sentinel) |s| {
try bw.writeAll("_s_");
try dg.renderValue(bw, child_type, s, .Other);
}
try bw.writeAll(";\n");
const rendered = buffer.toOwnedSlice();
errdefer dg.typedefs.allocator.free(rendered);
const name = rendered[name_index .. rendered.len - 2];
try dg.typedefs.ensureUnusedCapacity(1);
dg.typedefs.putAssumeCapacityNoClobber(
try t.copy(dg.typedefs_arena),
.{ .name = name, .rendered = rendered },
);
return name;
}
fn renderStructTypedef(dg: *DeclGen, t: Type) error{ OutOfMemory, AnalysisFail }![]const u8 {
const struct_obj = t.castTag(.@"struct").?.data; // Handle 0 bit types elsewhere.
const fqn = try struct_obj.getFullyQualifiedName(dg.module);
defer dg.typedefs.allocator.free(fqn);
var buffer = std.ArrayList(u8).init(dg.typedefs.allocator);
defer buffer.deinit();
try buffer.appendSlice("typedef struct {\n");
{
var it = struct_obj.fields.iterator();
while (it.next()) |entry| {
const field_ty = entry.value_ptr.ty;
if (!field_ty.hasRuntimeBits()) continue;
const alignment = entry.value_ptr.abi_align;
const name: CValue = .{ .identifier = entry.key_ptr.* };
try buffer.append(' ');
try dg.renderTypeAndName(buffer.writer(), field_ty, name, .Mut, alignment);
try buffer.appendSlice(";\n");
}
}
try buffer.appendSlice("} ");
const name_start = buffer.items.len;
try buffer.writer().print("zig_S_{};\n", .{fmtIdent(fqn)});
const rendered = buffer.toOwnedSlice();
errdefer dg.typedefs.allocator.free(rendered);
const name = rendered[name_start .. rendered.len - 2];
try dg.typedefs.ensureUnusedCapacity(1);
dg.typedefs.putAssumeCapacityNoClobber(
try t.copy(dg.typedefs_arena),
.{ .name = name, .rendered = rendered },
);
return name;
}
fn renderTupleTypedef(dg: *DeclGen, t: Type) error{ OutOfMemory, AnalysisFail }![]const u8 {
const tuple = t.tupleFields();
var buffer = std.ArrayList(u8).init(dg.typedefs.allocator);
defer buffer.deinit();
const writer = buffer.writer();
try buffer.appendSlice("typedef struct {\n");
{
for (tuple.types) |field_ty, i| {
const val = tuple.values[i];
if (val.tag() != .unreachable_value) continue;
var name = std.ArrayList(u8).init(dg.gpa);
defer name.deinit();
try name.writer().print("field_{d}", .{i});
try buffer.append(' ');
try dg.renderTypeAndName(writer, field_ty, .{ .bytes = name.items }, .Mut, 0);
try buffer.appendSlice(";\n");
}
}
try buffer.appendSlice("} ");
const name_start = buffer.items.len;
try writer.print("zig_T_{};\n", .{typeToCIdentifier(t, dg.module)});
const rendered = buffer.toOwnedSlice();
errdefer dg.typedefs.allocator.free(rendered);
const name = rendered[name_start .. rendered.len - 2];
try dg.typedefs.ensureUnusedCapacity(1);
dg.typedefs.putAssumeCapacityNoClobber(
try t.copy(dg.typedefs_arena),
.{ .name = name, .rendered = rendered },
);
return name;
}
fn renderUnionTypedef(dg: *DeclGen, t: Type) error{ OutOfMemory, AnalysisFail }![]const u8 {
const union_ty = t.cast(Type.Payload.Union).?.data;
const fqn = try union_ty.getFullyQualifiedName(dg.module);
defer dg.typedefs.allocator.free(fqn);
const target = dg.module.getTarget();
const layout = t.unionGetLayout(target);
var buffer = std.ArrayList(u8).init(dg.typedefs.allocator);
defer buffer.deinit();
try buffer.appendSlice("typedef ");
if (t.unionTagTypeSafety()) |tag_ty| {
const name: CValue = .{ .bytes = "tag" };
try buffer.appendSlice("struct {\n ");
if (layout.tag_size != 0) {
try dg.renderTypeAndName(buffer.writer(), tag_ty, name, .Mut, 0);
try buffer.appendSlice(";\n");
}
}
try buffer.appendSlice("union {\n");
{
var it = t.unionFields().iterator();
while (it.next()) |entry| {
const field_ty = entry.value_ptr.ty;
if (!field_ty.hasRuntimeBits()) continue;
const alignment = entry.value_ptr.abi_align;
const name: CValue = .{ .identifier = entry.key_ptr.* };
try buffer.append(' ');
try dg.renderTypeAndName(buffer.writer(), field_ty, name, .Mut, alignment);
try buffer.appendSlice(";\n");
}
}
try buffer.appendSlice("} ");
if (t.unionTagTypeSafety()) |_| {
try buffer.appendSlice("payload;\n} ");
}
const name_start = buffer.items.len;
try buffer.writer().print("zig_U_{};\n", .{fmtIdent(fqn)});
const rendered = buffer.toOwnedSlice();
errdefer dg.typedefs.allocator.free(rendered);
const name = rendered[name_start .. rendered.len - 2];
try dg.typedefs.ensureUnusedCapacity(1);
dg.typedefs.putAssumeCapacityNoClobber(
try t.copy(dg.typedefs_arena),
.{ .name = name, .rendered = rendered },
);
return name;
}
fn renderErrorUnionTypedef(dg: *DeclGen, t: Type) error{ OutOfMemory, AnalysisFail }![]const u8 {
const payload_ty = t.errorUnionPayload();
const error_ty = t.errorUnionSet();
var buffer = std.ArrayList(u8).init(dg.typedefs.allocator);
defer buffer.deinit();
const bw = buffer.writer();
const payload_name = CValue{ .bytes = "payload" };
const target = dg.module.getTarget();
const payload_align = payload_ty.abiAlignment(target);
const error_align = Type.anyerror.abiAlignment(target);
if (error_align > payload_align) {
try bw.writeAll("typedef struct { ");
try dg.renderTypeAndName(bw, payload_ty, payload_name, .Mut, 0);
try bw.writeAll("; uint16_t error; } ");
} else {
try bw.writeAll("typedef struct { uint16_t error; ");
try dg.renderTypeAndName(bw, payload_ty, payload_name, .Mut, 0);
try bw.writeAll("; } ");
}
const name_index = buffer.items.len;
if (error_ty.castTag(.error_set_inferred)) |inf_err_set_payload| {
const func = inf_err_set_payload.data.func;
try bw.writeAll("zig_E_");
try dg.renderDeclName(bw, func.owner_decl);
try bw.writeAll(";\n");
} else {
try bw.print("zig_E_{s}_{s};\n", .{
typeToCIdentifier(error_ty, dg.module), typeToCIdentifier(payload_ty, dg.module),
});
}
const rendered = buffer.toOwnedSlice();
errdefer dg.typedefs.allocator.free(rendered);
const name = rendered[name_index .. rendered.len - 2];
try dg.typedefs.ensureUnusedCapacity(1);
dg.typedefs.putAssumeCapacityNoClobber(
try t.copy(dg.typedefs_arena),
.{ .name = name, .rendered = rendered },
);
return name;
}
fn renderArrayTypedef(dg: *DeclGen, t: Type) error{ OutOfMemory, AnalysisFail }![]const u8 {
var buffer = std.ArrayList(u8).init(dg.typedefs.allocator);
defer buffer.deinit();
const bw = buffer.writer();
const elem_type = t.elemType();
const sentinel_bit = @boolToInt(t.sentinel() != null);
const c_len = t.arrayLen() + sentinel_bit;
try bw.writeAll("typedef ");
try dg.renderType(bw, elem_type);
const name_start = buffer.items.len + 1;
try bw.print(" zig_A_{s}_{d}", .{ typeToCIdentifier(elem_type, dg.module), c_len });
const name_end = buffer.items.len;
try bw.print("[{d}];\n", .{c_len});
const rendered = buffer.toOwnedSlice();
errdefer dg.typedefs.allocator.free(rendered);
const name = rendered[name_start..name_end];
try dg.typedefs.ensureUnusedCapacity(1);
dg.typedefs.putAssumeCapacityNoClobber(
try t.copy(dg.typedefs_arena),
.{ .name = name, .rendered = rendered },
);
return name;
}
fn renderOptionalTypedef(dg: *DeclGen, t: Type, child_type: Type) error{ OutOfMemory, AnalysisFail }![]const u8 {
var buffer = std.ArrayList(u8).init(dg.typedefs.allocator);
defer buffer.deinit();
const bw = buffer.writer();
try bw.writeAll("typedef struct { ");
const payload_name = CValue{ .bytes = "payload" };
try dg.renderTypeAndName(bw, child_type, payload_name, .Mut, 0);
try bw.writeAll("; bool is_null; } ");
const name_index = buffer.items.len;
try bw.print("zig_Q_{s};\n", .{typeToCIdentifier(child_type, dg.module)});
const rendered = buffer.toOwnedSlice();
errdefer dg.typedefs.allocator.free(rendered);
const name = rendered[name_index .. rendered.len - 2];
try dg.typedefs.ensureUnusedCapacity(1);
dg.typedefs.putAssumeCapacityNoClobber(
try t.copy(dg.typedefs_arena),
.{ .name = name, .rendered = rendered },
);
return name;
}
/// Renders a type as a single identifier, generating intermediate typedefs
/// if necessary.
///
/// This is guaranteed to be valid in both typedefs and declarations/definitions.
///
/// There are three type formats in total that we support rendering:
/// | Function | Example 1 (*u8) | Example 2 ([10]*u8) |
/// |---------------------|-----------------|---------------------|
/// | `renderTypecast` | "uint8_t *" | "uint8_t *[10]" |
/// | `renderTypeAndName` | "uint8_t *name" | "uint8_t *name[10]" |
/// | `renderType` | "uint8_t *" | "zig_A_uint8_t_10" |
///
fn renderType(dg: *DeclGen, w: anytype, t: Type) error{ OutOfMemory, AnalysisFail }!void {
const target = dg.module.getTarget();
switch (t.zigTypeTag()) {
.NoReturn, .Void => try w.writeAll("void"),
.Bool => try w.writeAll("bool"),
.Int => {
switch (t.tag()) {
.u1, .u8 => try w.writeAll("uint8_t"),
.i8 => try w.writeAll("int8_t"),
.u16 => try w.writeAll("uint16_t"),
.i16 => try w.writeAll("int16_t"),
.u32 => try w.writeAll("uint32_t"),
.i32 => try w.writeAll("int32_t"),
.u64 => try w.writeAll("uint64_t"),
.i64 => try w.writeAll("int64_t"),
.u128 => try w.writeAll("uint128_t"),
.i128 => try w.writeAll("int128_t"),
.usize => try w.writeAll("uintptr_t"),
.isize => try w.writeAll("intptr_t"),
.c_short => try w.writeAll("short"),
.c_ushort => try w.writeAll("unsigned short"),
.c_int => try w.writeAll("int"),
.c_uint => try w.writeAll("unsigned int"),
.c_long => try w.writeAll("long"),
.c_ulong => try w.writeAll("unsigned long"),
.c_longlong => try w.writeAll("long long"),
.c_ulonglong => try w.writeAll("unsigned long long"),
.int_signed, .int_unsigned => {
const info = t.intInfo(target);
const sign_prefix = switch (info.signedness) {
.signed => "",
.unsigned => "u",
};
const c_bits = toCIntBits(info.bits) orelse
return dg.fail("TODO: C backend: implement integer types larger than 128 bits", .{});
try w.print("{s}int{d}_t", .{ sign_prefix, c_bits });
},
else => unreachable,
}
},
.Float => {
switch (t.tag()) {
.f32 => try w.writeAll("float"),
.f64 => try w.writeAll("double"),
.c_longdouble => try w.writeAll("long double"),
.f16 => return dg.fail("TODO: C backend: implement float type f16", .{}),
.f128 => return dg.fail("TODO: C backend: implement float type f128", .{}),
else => unreachable,
}
},
.Pointer => {
if (t.isSlice()) {
const name = dg.getTypedefName(t) orelse
try dg.renderSliceTypedef(t);
return w.writeAll(name);
}
if (t.castPtrToFn()) |fn_ty| {
const name = dg.getTypedefName(t) orelse
try dg.renderPtrToFnTypedef(t, fn_ty);
return w.writeAll(name);
}
try dg.renderType(w, t.elemType());
if (t.isConstPtr()) {
try w.writeAll(" const");
}
if (t.isVolatilePtr()) {
try w.writeAll(" volatile");
}
return w.writeAll(" *");
},
.Array => {
const name = dg.getTypedefName(t) orelse
try dg.renderArrayTypedef(t);
return w.writeAll(name);
},
.Optional => {
var opt_buf: Type.Payload.ElemType = undefined;
const child_type = t.optionalChild(&opt_buf);
if (!child_type.hasRuntimeBitsIgnoreComptime()) {
return w.writeAll("bool");
}
if (t.optionalReprIsPayload()) {
return dg.renderType(w, child_type);
}
const name = dg.getTypedefName(t) orelse
try dg.renderOptionalTypedef(t, child_type);
return w.writeAll(name);
},
.ErrorSet => {
comptime assert(Type.anyerror.abiSize(builtin.target) == 2);
return w.writeAll("uint16_t");
},
.ErrorUnion => {
const payload_ty = t.errorUnionPayload();
if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
return dg.renderType(w, Type.anyerror);
}
const name = dg.getTypedefName(t) orelse
try dg.renderErrorUnionTypedef(t);
return w.writeAll(name);
},
.Struct => {
const name = dg.getTypedefName(t) orelse if (t.isTuple() or t.tag() == .anon_struct)
try dg.renderTupleTypedef(t)
else
try dg.renderStructTypedef(t);
return w.writeAll(name);
},
.Union => {
const name = dg.getTypedefName(t) orelse
try dg.renderUnionTypedef(t);
return w.writeAll(name);
},
.Enum => {
// For enums, we simply use the integer tag type.
var int_tag_ty_buffer: Type.Payload.Bits = undefined;
const int_tag_ty = t.intTagType(&int_tag_ty_buffer);
try dg.renderType(w, int_tag_ty);
},
.Opaque => return w.writeAll("void"),
.Frame,
.AnyFrame,
.Vector,
=> |tag| return dg.fail("TODO: C backend: implement value of type {s}", .{
@tagName(tag),
}),
.Fn => unreachable, // This is a function body, not a function pointer.
.Null,
.Undefined,
.EnumLiteral,
.ComptimeFloat,
.ComptimeInt,
.Type,
=> unreachable, // must be const or comptime
.BoundFn => unreachable, // this type will be deleted from the language
}
}
/// Renders a type in C typecast format.
///
/// This is guaranteed to be valid in a typecast expression, but not
/// necessarily in a variable/field declaration.
///
/// There are three type formats in total that we support rendering:
/// | Function | Example 1 (*u8) | Example 2 ([10]*u8) |
/// |---------------------|-----------------|---------------------|
/// | `renderTypecast` | "uint8_t *" | "uint8_t *[10]" |
/// | `renderTypeAndName` | "uint8_t *name" | "uint8_t *name[10]" |
/// | `renderType` | "uint8_t *" | "zig_A_uint8_t_10" |
///
fn renderTypecast(
dg: *DeclGen,
w: anytype,
ty: Type,
) error{ OutOfMemory, AnalysisFail }!void {
const name = CValue{ .bytes = "" };
return renderTypeAndName(dg, w, ty, name, .Mut, 0);
}
/// Renders a type and name in field declaration/definition format.
///
/// There are three type formats in total that we support rendering:
/// | Function | Example 1 (*u8) | Example 2 ([10]*u8) |
/// |---------------------|-----------------|---------------------|
/// | `renderTypecast` | "uint8_t *" | "uint8_t *[10]" |
/// | `renderTypeAndName` | "uint8_t *name" | "uint8_t *name[10]" |
/// | `renderType` | "uint8_t *" | "zig_A_uint8_t_10" |
///
fn renderTypeAndName(
dg: *DeclGen,
w: anytype,
ty: Type,
name: CValue,
mutability: Mutability,
alignment: u32,
) error{ OutOfMemory, AnalysisFail }!void {
var suffix = std.ArrayList(u8).init(dg.gpa);
defer suffix.deinit();
// Any top-level array types are rendered here as a suffix, which
// avoids creating typedefs for every array type
var render_ty = ty;
while (render_ty.zigTypeTag() == .Array) {
const sentinel_bit = @boolToInt(render_ty.sentinel() != null);
const c_len = render_ty.arrayLen() + sentinel_bit;
try suffix.writer().print("[{d}]", .{c_len});
render_ty = render_ty.elemType();
}
if (alignment != 0)
try w.print("ZIG_ALIGN({}) ", .{alignment});
try dg.renderType(w, render_ty);
const const_prefix = switch (mutability) {
.Const => "const ",
.Mut => "",
};
try w.print(" {s}", .{const_prefix});
try dg.writeCValue(w, name);
try w.writeAll(suffix.items);
}
fn declIsGlobal(dg: *DeclGen, tv: TypedValue) bool {
switch (tv.val.tag()) {
.extern_fn => return true,
.function => {
const func = tv.val.castTag(.function).?.data;
return dg.module.decl_exports.contains(func.owner_decl);
},
.variable => {
const variable = tv.val.castTag(.variable).?.data;
return dg.module.decl_exports.contains(variable.owner_decl);
},
else => unreachable,
}
}
fn writeCValue(dg: DeclGen, w: anytype, c_value: CValue) !void {
switch (c_value) {
.none => unreachable,
.local => |i| return w.print("t{d}", .{i}),
.local_ref => |i| return w.print("&t{d}", .{i}),
.constant => unreachable,
.arg => |i| return w.print("a{d}", .{i}),
.decl => |decl| return dg.renderDeclName(w, decl),
.decl_ref => |decl| {
try w.writeByte('&');
return dg.renderDeclName(w, decl);
},
.undefined_ptr => {
const target = dg.module.getTarget();
switch (target.cpu.arch.ptrBitWidth()) {
32 => try w.writeAll("(void *)0xaaaaaaaa"),
64 => try w.writeAll("(void *)0xaaaaaaaaaaaaaaaa"),
else => unreachable,
}
},
.identifier => |ident| return w.print("{ }", .{fmtIdent(ident)}),
.bytes => |bytes| return w.writeAll(bytes),
}
}
fn writeCValueDeref(dg: DeclGen, w: anytype, c_value: CValue) !void {
switch (c_value) {
.none => unreachable,
.local => |i| return w.print("(*t{d})", .{i}),
.local_ref => |i| return w.print("t{d}", .{i}),
.constant => unreachable,
.arg => |i| return w.print("(*a{d})", .{i}),
.decl => |decl| {
try w.writeAll("(*");
try dg.renderDeclName(w, decl);
return w.writeByte(')');
},
.decl_ref => |decl| return dg.renderDeclName(w, decl),
.undefined_ptr => unreachable,
.identifier => |ident| return w.print("(*{ })", .{fmtIdent(ident)}),
.bytes => |bytes| {
try w.writeAll("(*");
try w.writeAll(bytes);
return w.writeByte(')');
},
}
}
fn renderDeclName(dg: DeclGen, writer: anytype, decl_index: Decl.Index) !void {
const decl = dg.module.declPtr(decl_index);
dg.module.markDeclAlive(decl);
if (dg.module.decl_exports.get(decl_index)) |exports| {
return writer.writeAll(exports[0].options.name);
} else if (decl.val.tag() == .extern_fn) {
return writer.writeAll(mem.sliceTo(decl.name, 0));
} else {
const gpa = dg.module.gpa;
const name = try decl.getFullyQualifiedName(dg.module);
defer gpa.free(name);
return writer.print("{ }", .{fmtIdent(name)});
}
}
};
pub fn genFunc(f: *Function) !void {
const tracy = trace(@src());
defer tracy.end();
const o = &f.object;
o.code_header = std.ArrayList(u8).init(f.object.dg.gpa);
defer o.code_header.deinit();
const is_global = o.dg.module.decl_exports.contains(f.func.owner_decl);
const fwd_decl_writer = o.dg.fwd_decl.writer();
if (is_global) {
try fwd_decl_writer.writeAll("ZIG_EXTERN_C ");
}
try o.dg.renderFunctionSignature(fwd_decl_writer, is_global);
try fwd_decl_writer.writeAll(";\n");
try o.indent_writer.insertNewline();
try o.dg.renderFunctionSignature(o.writer(), is_global);
try o.writer().writeByte(' ');
// In case we need to use the header, populate it with a copy of the function
// signature here. We anticipate a brace, newline, and space.
try o.code_header.ensureUnusedCapacity(o.code.items.len + 3);
o.code_header.appendSliceAssumeCapacity(o.code.items);
o.code_header.appendSliceAssumeCapacity("{\n ");
const empty_header_len = o.code_header.items.len;
const main_body = f.air.getMainBody();
try genBody(f, main_body);
try o.indent_writer.insertNewline();
// If we have a header to insert, append the body to the header
// and then return the result, freeing the body.
if (o.code_header.items.len > empty_header_len) {
try o.code_header.appendSlice(o.code.items[empty_header_len..]);
mem.swap(std.ArrayList(u8), &o.code, &o.code_header);
}
}
pub fn genDecl(o: *Object) !void {
const tracy = trace(@src());
defer tracy.end();
const tv: TypedValue = .{
.ty = o.dg.decl.ty,
.val = o.dg.decl.val,
};
if (tv.val.tag() == .extern_fn) {
const writer = o.writer();
try writer.writeAll("ZIG_EXTERN_C ");
try o.dg.renderFunctionSignature(writer, true);
try writer.writeAll(";\n");
} else if (tv.val.castTag(.variable)) |var_payload| {
const variable: *Module.Var = var_payload.data;
const is_global = o.dg.declIsGlobal(tv) or variable.is_extern;
const fwd_decl_writer = o.dg.fwd_decl.writer();
if (is_global) {
try fwd_decl_writer.writeAll("ZIG_EXTERN_C ");
}
if (variable.is_threadlocal) {
try fwd_decl_writer.writeAll("zig_threadlocal ");
}
const decl_c_value: CValue = if (is_global) .{
.bytes = mem.span(o.dg.decl.name),
} else .{
.decl = o.dg.decl_index,
};
try o.dg.renderTypeAndName(fwd_decl_writer, o.dg.decl.ty, decl_c_value, .Mut, o.dg.decl.@"align");
try fwd_decl_writer.writeAll(";\n");
if (variable.init.isUndefDeep()) {
return;
}
try o.indent_writer.insertNewline();
const w = o.writer();
try o.dg.renderTypeAndName(w, o.dg.decl.ty, decl_c_value, .Mut, o.dg.decl.@"align");
try w.writeAll(" = ");
if (variable.init.tag() != .unreachable_value) {
try o.dg.renderValue(w, tv.ty, variable.init, .Other);
}
try w.writeAll(";");
try o.indent_writer.insertNewline();
} else {
const writer = o.writer();
try writer.writeAll("static ");
// TODO ask the Decl if it is const
// https://github.com/ziglang/zig/issues/7582
const decl_c_value: CValue = .{ .decl = o.dg.decl_index };
try o.dg.renderTypeAndName(writer, tv.ty, decl_c_value, .Mut, o.dg.decl.@"align");
try writer.writeAll(" = ");
try o.dg.renderValue(writer, tv.ty, tv.val, .Other);
try writer.writeAll(";\n");
}
}
pub fn genHeader(dg: *DeclGen) error{ AnalysisFail, OutOfMemory }!void {
const tracy = trace(@src());
defer tracy.end();
const tv: TypedValue = .{
.ty = dg.decl.ty,
.val = dg.decl.val,
};
const writer = dg.fwd_decl.writer();
switch (tv.ty.zigTypeTag()) {
.Fn => {
const is_global = dg.declIsGlobal(tv);
if (is_global) {
try writer.writeAll("ZIG_EXTERN_C ");
try dg.renderFunctionSignature(writer, is_global);
try dg.fwd_decl.appendSlice(";\n");
}
},
else => {},
}
}
fn genBody(f: *Function, body: []const Air.Inst.Index) error{ AnalysisFail, OutOfMemory }!void {
const writer = f.object.writer();
if (body.len == 0) {
try writer.writeAll("{}");
return;
}
try writer.writeAll("{\n");
f.object.indent_writer.pushIndent();
const air_tags = f.air.instructions.items(.tag);
for (body) |inst| {
const result_value = switch (air_tags[inst]) {
// zig fmt: off
.constant => unreachable, // excluded from function bodies
.const_ty => unreachable, // excluded from function bodies
.arg => airArg(f),
.breakpoint => try airBreakpoint(f),
.ret_addr => try airRetAddr(f, inst),
.frame_addr => try airFrameAddress(f, inst),
.unreach => try airUnreach(f),
.fence => try airFence(f, inst),
.ptr_add => try airPtrAddSub(f, inst, " + "),
.ptr_sub => try airPtrAddSub(f, inst, " - "),
// TODO use a different strategy for add, sub, mul, div
// that communicates to the optimizer that wrapping is UB.
.add => try airBinOp (f, inst, " + "),
.sub => try airBinOp (f, inst, " - "),
.mul => try airBinOp (f, inst, " * "),
.div_float, .div_exact => try airBinOp( f, inst, " / "),
.rem => try airBinOp( f, inst, " % "),
.div_trunc => blk: {
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const lhs_ty = f.air.typeOf(bin_op.lhs);
// For binary operations @TypeOf(lhs)==@TypeOf(rhs),
// so we only check one.
break :blk if (lhs_ty.isInt())
try airBinOp(f, inst, " / ")
else
try airBinOpBuiltinCall(f, inst, "div_trunc");
},
.div_floor => try airBinOpBuiltinCall(f, inst, "div_floor"),
.mod => try airBinOpBuiltinCall(f, inst, "mod"),
.addwrap => try airWrapOp(f, inst, " + ", "addw_"),
.subwrap => try airWrapOp(f, inst, " - ", "subw_"),
.mulwrap => try airWrapOp(f, inst, " * ", "mulw_"),
.add_sat => try airSatOp(f, inst, "adds_"),
.sub_sat => try airSatOp(f, inst, "subs_"),
.mul_sat => try airSatOp(f, inst, "muls_"),
.shl_sat => try airSatOp(f, inst, "shls_"),
.neg => try airNeg(f, inst),
.sqrt,
.sin,
.cos,
.tan,
.exp,
.exp2,
.log,
.log2,
.log10,
.fabs,
.floor,
.ceil,
.round,
.trunc_float,
=> |tag| return f.fail("TODO: C backend: implement unary op for tag '{s}'", .{@tagName(tag)}),
.mul_add => try airMulAdd(f, inst),
.add_with_overflow => try airOverflow(f, inst, "addo_"),
.sub_with_overflow => try airOverflow(f, inst, "subo_"),
.mul_with_overflow => try airOverflow(f, inst, "mulo_"),
.shl_with_overflow => try airOverflow(f, inst, "shlo_"),
.min => try airMinMax(f, inst, "<"),
.max => try airMinMax(f, inst, ">"),
.slice => try airSlice(f, inst),
.cmp_gt => try airBinOp(f, inst, " > "),
.cmp_gte => try airBinOp(f, inst, " >= "),
.cmp_lt => try airBinOp(f, inst, " < "),
.cmp_lte => try airBinOp(f, inst, " <= "),
.cmp_eq => try airEquality(f, inst, "((", "=="),
.cmp_neq => try airEquality(f, inst, "!((", "!="),
.cmp_vector => return f.fail("TODO: C backend: implement cmp_vector", .{}),
.cmp_lt_errors_len => return f.fail("TODO: C backend: implement cmp_lt_errors_len", .{}),
// bool_and and bool_or are non-short-circuit operations
.bool_and => try airBinOp(f, inst, " & "),
.bool_or => try airBinOp(f, inst, " | "),
.bit_and => try airBinOp(f, inst, " & "),
.bit_or => try airBinOp(f, inst, " | "),
.xor => try airBinOp(f, inst, " ^ "),
.shr, .shr_exact => try airBinOp(f, inst, " >> "),
.shl, .shl_exact => try airBinOp(f, inst, " << "),
.not => try airNot (f, inst),
.optional_payload => try airOptionalPayload(f, inst),
.optional_payload_ptr => try airOptionalPayloadPtr(f, inst),
.optional_payload_ptr_set => try airOptionalPayloadPtrSet(f, inst),
.wrap_optional => try airWrapOptional(f, inst),
.is_err => try airIsErr(f, inst, false, "!="),
.is_non_err => try airIsErr(f, inst, false, "=="),
.is_err_ptr => try airIsErr(f, inst, true, "!="),
.is_non_err_ptr => try airIsErr(f, inst, true, "=="),
.is_null => try airIsNull(f, inst, "==", ""),
.is_non_null => try airIsNull(f, inst, "!=", ""),
.is_null_ptr => try airIsNull(f, inst, "==", "[0]"),
.is_non_null_ptr => try airIsNull(f, inst, "!=", "[0]"),
.alloc => try airAlloc(f, inst),
.ret_ptr => try airRetPtr(f, inst),
.assembly => try airAsm(f, inst),
.block => try airBlock(f, inst),
.bitcast => try airBitcast(f, inst),
.dbg_stmt => try airDbgStmt(f, inst),
.intcast => try airIntCast(f, inst),
.trunc => try airTrunc(f, inst),
.bool_to_int => try airBoolToInt(f, inst),
.load => try airLoad(f, inst),
.ret => try airRet(f, inst),
.ret_load => try airRetLoad(f, inst),
.store => try airStore(f, inst),
.loop => try airLoop(f, inst),
.cond_br => try airCondBr(f, inst),
.br => try airBr(f, inst),
.switch_br => try airSwitchBr(f, inst),
.struct_field_ptr => try airStructFieldPtr(f, inst),
.array_to_slice => try airArrayToSlice(f, inst),
.cmpxchg_weak => try airCmpxchg(f, inst, "weak"),
.cmpxchg_strong => try airCmpxchg(f, inst, "strong"),
.atomic_rmw => try airAtomicRmw(f, inst),
.atomic_load => try airAtomicLoad(f, inst),
.memset => try airMemset(f, inst),
.memcpy => try airMemcpy(f, inst),
.set_union_tag => try airSetUnionTag(f, inst),
.get_union_tag => try airGetUnionTag(f, inst),
.clz => try airBuiltinCall(f, inst, "clz"),
.ctz => try airBuiltinCall(f, inst, "ctz"),
.popcount => try airBuiltinCall(f, inst, "popcount"),
.byte_swap => try airBuiltinCall(f, inst, "byte_swap"),
.bit_reverse => try airBuiltinCall(f, inst, "bit_reverse"),
.tag_name => try airTagName(f, inst),
.error_name => try airErrorName(f, inst),
.splat => try airSplat(f, inst),
.select => try airSelect(f, inst),
.shuffle => try airShuffle(f, inst),
.reduce => try airReduce(f, inst),
.aggregate_init => try airAggregateInit(f, inst),
.union_init => try airUnionInit(f, inst),
.prefetch => try airPrefetch(f, inst),
.@"try" => try airTry(f, inst),
.try_ptr => try airTryPtr(f, inst),
.dbg_var_ptr,
.dbg_var_val,
=> try airDbgVar(f, inst),
.dbg_inline_begin,
.dbg_inline_end,
=> try airDbgInline(f, inst),
.dbg_block_begin,
.dbg_block_end,
=> CValue{ .none = {} },
.call => try airCall(f, inst, .auto),
.call_always_tail => try airCall(f, inst, .always_tail),
.call_never_tail => try airCall(f, inst, .never_tail),
.call_never_inline => try airCall(f, inst, .never_inline),
.int_to_float,
.float_to_int,
.fptrunc,
.fpext,
=> try airSimpleCast(f, inst),
.ptrtoint => try airPtrToInt(f, inst),
.atomic_store_unordered => try airAtomicStore(f, inst, toMemoryOrder(.Unordered)),
.atomic_store_monotonic => try airAtomicStore(f, inst, toMemoryOrder(.Monotonic)),
.atomic_store_release => try airAtomicStore(f, inst, toMemoryOrder(.Release)),
.atomic_store_seq_cst => try airAtomicStore(f, inst, toMemoryOrder(.SeqCst)),
.struct_field_ptr_index_0 => try airStructFieldPtrIndex(f, inst, 0),
.struct_field_ptr_index_1 => try airStructFieldPtrIndex(f, inst, 1),
.struct_field_ptr_index_2 => try airStructFieldPtrIndex(f, inst, 2),
.struct_field_ptr_index_3 => try airStructFieldPtrIndex(f, inst, 3),
.field_parent_ptr => try airFieldParentPtr(f, inst),
.struct_field_val => try airStructFieldVal(f, inst),
.slice_ptr => try airSliceField(f, inst, ".ptr;\n"),
.slice_len => try airSliceField(f, inst, ".len;\n"),
.ptr_slice_len_ptr => try airPtrSliceFieldPtr(f, inst, ".len;\n"),
.ptr_slice_ptr_ptr => try airPtrSliceFieldPtr(f, inst, ".ptr;\n"),
.ptr_elem_val => try airPtrElemVal(f, inst),
.ptr_elem_ptr => try airPtrElemPtr(f, inst),
.slice_elem_val => try airSliceElemVal(f, inst),
.slice_elem_ptr => try airSliceElemPtr(f, inst),
.array_elem_val => try airArrayElemVal(f, inst),
.unwrap_errunion_payload => try airUnwrapErrUnionPay(f, inst, ""),
.unwrap_errunion_payload_ptr => try airUnwrapErrUnionPay(f, inst, "&"),
.unwrap_errunion_err => try airUnwrapErrUnionErr(f, inst),
.unwrap_errunion_err_ptr => try airUnwrapErrUnionErr(f, inst),
.wrap_errunion_payload => try airWrapErrUnionPay(f, inst),
.wrap_errunion_err => try airWrapErrUnionErr(f, inst),
.errunion_payload_ptr_set => try airErrUnionPayloadPtrSet(f, inst),
.err_return_trace => try airErrReturnTrace(f, inst),
.set_err_return_trace => try airSetErrReturnTrace(f, inst),
.wasm_memory_size => try airWasmMemorySize(f, inst),
.wasm_memory_grow => try airWasmMemoryGrow(f, inst),
.add_optimized,
.addwrap_optimized,
.sub_optimized,
.subwrap_optimized,
.mul_optimized,
.mulwrap_optimized,
.div_float_optimized,
.div_trunc_optimized,
.div_floor_optimized,
.div_exact_optimized,
.rem_optimized,
.mod_optimized,
.neg_optimized,
.cmp_lt_optimized,
.cmp_lte_optimized,
.cmp_eq_optimized,
.cmp_gte_optimized,
.cmp_gt_optimized,
.cmp_neq_optimized,
.cmp_vector_optimized,
.reduce_optimized,
.float_to_int_optimized,
=> return f.fail("TODO implement optimized float mode", .{}),
.is_named_enum_value => return f.fail("TODO: C backend: implement is_named_enum_value", .{}),
.error_set_has_value => return f.fail("TODO: C backend: implement error_set_has_value", .{}),
// zig fmt: on
};
switch (result_value) {
.none => {},
else => try f.value_map.putNoClobber(Air.indexToRef(inst), result_value),
}
}
f.object.indent_writer.popIndent();
try writer.writeAll("}");
}
fn airSliceField(f: *Function, inst: Air.Inst.Index, suffix: []const u8) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const operand = try f.resolveInst(ty_op.operand);
const writer = f.object.writer();
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
try f.writeCValue(writer, operand);
try writer.writeAll(suffix);
return local;
}
fn airPtrSliceFieldPtr(f: *Function, inst: Air.Inst.Index, suffix: []const u8) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const operand = try f.resolveInst(ty_op.operand);
const writer = f.object.writer();
_ = writer;
_ = operand;
_ = suffix;
return f.fail("TODO: C backend: airPtrSliceFieldPtr", .{});
}
fn airPtrElemVal(f: *Function, inst: Air.Inst.Index) !CValue {
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const ptr_ty = f.air.typeOf(bin_op.lhs);
if (!ptr_ty.isVolatilePtr() and f.liveness.isUnused(inst)) return CValue.none;
const ptr = try f.resolveInst(bin_op.lhs);
const index = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const local = try f.allocLocal(f.air.typeOfIndex(inst), .Const);
try writer.writeAll(" = ");
try f.writeCValue(writer, ptr);
try writer.writeByte('[');
try f.writeCValue(writer, index);
try writer.writeAll("];\n");
return local;
}
fn airPtrElemPtr(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const bin_op = f.air.extraData(Air.Bin, ty_pl.payload).data;
const ptr_ty = f.air.typeOf(bin_op.lhs);
const ptr = try f.resolveInst(bin_op.lhs);
const index = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const local = try f.allocLocal(f.air.typeOfIndex(inst), .Const);
try writer.writeAll(" = &(");
if (ptr_ty.ptrSize() == .One) {
// It's a pointer to an array, so we need to de-reference.
try f.writeCValueDeref(writer, ptr);
} else {
try f.writeCValue(writer, ptr);
}
try writer.writeAll(")[");
try f.writeCValue(writer, index);
try writer.writeAll("];\n");
return local;
}
fn airSliceElemVal(f: *Function, inst: Air.Inst.Index) !CValue {
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const slice_ty = f.air.typeOf(bin_op.lhs);
if (!slice_ty.isVolatilePtr() and f.liveness.isUnused(inst)) return CValue.none;
const slice = try f.resolveInst(bin_op.lhs);
const index = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const local = try f.allocLocal(f.air.typeOfIndex(inst), .Const);
try writer.writeAll(" = ");
try f.writeCValue(writer, slice);
try writer.writeAll(".ptr[");
try f.writeCValue(writer, index);
try writer.writeAll("];\n");
return local;
}
fn airSliceElemPtr(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const bin_op = f.air.extraData(Air.Bin, ty_pl.payload).data;
const slice = try f.resolveInst(bin_op.lhs);
const index = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const local = try f.allocLocal(f.air.typeOfIndex(inst), .Const);
try writer.writeAll(" = &");
try f.writeCValue(writer, slice);
try writer.writeAll(".ptr[");
try f.writeCValue(writer, index);
try writer.writeAll("];\n");
return local;
}
fn airArrayElemVal(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const array = try f.resolveInst(bin_op.lhs);
const index = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const local = try f.allocLocal(f.air.typeOfIndex(inst), .Const);
try writer.writeAll(" = ");
try f.writeCValue(writer, array);
try writer.writeAll("[");
try f.writeCValue(writer, index);
try writer.writeAll("];\n");
return local;
}
fn airAlloc(f: *Function, inst: Air.Inst.Index) !CValue {
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const elem_type = inst_ty.elemType();
const mutability: Mutability = if (inst_ty.isConstPtr()) .Const else .Mut;
if (!elem_type.isFnOrHasRuntimeBitsIgnoreComptime()) {
return CValue.undefined_ptr;
}
const target = f.object.dg.module.getTarget();
// First line: the variable used as data storage.
const local = try f.allocAlignedLocal(elem_type, mutability, inst_ty.ptrAlignment(target));
try writer.writeAll(";\n");
return CValue{ .local_ref = local.local };
}
fn airRetPtr(f: *Function, inst: Air.Inst.Index) !CValue {
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
// First line: the variable used as data storage.
const elem_type = inst_ty.elemType();
const local = try f.allocLocal(elem_type, .Mut);
try writer.writeAll(";\n");
return CValue{ .local_ref = local.local };
}
fn airArg(f: *Function) CValue {
const i = f.next_arg_index;
f.next_arg_index += 1;
return .{ .arg = i };
}
fn airLoad(f: *Function, inst: Air.Inst.Index) !CValue {
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const is_volatile = f.air.typeOf(ty_op.operand).isVolatilePtr();
if (!is_volatile and f.liveness.isUnused(inst))
return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const is_array = inst_ty.zigTypeTag() == .Array;
const operand = try f.resolveInst(ty_op.operand);
const writer = f.object.writer();
// We need to separately initialize arrays with a memcpy so they must be mutable.
const local = try f.allocLocal(inst_ty, if (is_array) .Mut else .Const);
if (is_array) {
// Insert a memcpy to initialize this array. The source operand is always a pointer
// and thus we only need to know size/type information from the local type/dest.
try writer.writeAll(";");
try f.object.indent_writer.insertNewline();
try writer.writeAll("memcpy(");
try f.writeCValue(writer, local);
try writer.writeAll(", ");
try f.writeCValue(writer, operand);
try writer.writeAll(", sizeof(");
try f.writeCValue(writer, local);
try writer.writeAll("));\n");
} else {
try writer.writeAll(" = ");
try f.writeCValueDeref(writer, operand);
try writer.writeAll(";\n");
}
return local;
}
fn airRet(f: *Function, inst: Air.Inst.Index) !CValue {
const un_op = f.air.instructions.items(.data)[inst].un_op;
const writer = f.object.writer();
const ret_ty = f.air.typeOf(un_op);
if (ret_ty.isFnOrHasRuntimeBitsIgnoreComptime()) {
const operand = try f.resolveInst(un_op);
try writer.writeAll("return ");
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
} else if (ret_ty.isError()) {
try writer.writeAll("return 0;");
} else {
try writer.writeAll("return;\n");
}
return CValue.none;
}
fn airRetLoad(f: *Function, inst: Air.Inst.Index) !CValue {
const un_op = f.air.instructions.items(.data)[inst].un_op;
const writer = f.object.writer();
const ptr_ty = f.air.typeOf(un_op);
const ret_ty = ptr_ty.childType();
if (ret_ty.isFnOrHasRuntimeBitsIgnoreComptime()) {
const ptr = try f.resolveInst(un_op);
try writer.writeAll("return *");
try f.writeCValue(writer, ptr);
try writer.writeAll(";\n");
} else if (ret_ty.isError()) {
try writer.writeAll("return 0;\n");
} else {
try writer.writeAll("return;\n");
}
return CValue.none;
}
fn airIntCast(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const operand = try f.resolveInst(ty_op.operand);
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = (");
try f.renderTypecast(writer, inst_ty);
try writer.writeAll(")");
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
return local;
}
fn airTrunc(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const target = f.object.dg.module.getTarget();
const dest_int_info = inst_ty.intInfo(target);
const dest_bits = dest_int_info.bits;
try writer.writeAll(" = ");
if (dest_bits >= 8 and std.math.isPowerOfTwo(dest_bits)) {
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
return local;
}
switch (dest_int_info.signedness) {
.unsigned => {
try f.writeCValue(writer, operand);
const mask = (@as(u65, 1) << @intCast(u7, dest_bits)) - 1;
try writer.print(" & {d}ULL;\n", .{mask});
return local;
},
.signed => {
const operand_ty = f.air.typeOf(ty_op.operand);
const c_bits = toCIntBits(operand_ty.intInfo(target).bits) orelse
return f.fail("TODO: C backend: implement integer types larger than 128 bits", .{});
const shift_rhs = c_bits - dest_bits;
try writer.print("(int{d}_t)((uint{d}_t)", .{ c_bits, c_bits });
try f.writeCValue(writer, operand);
try writer.print(" << {d}) >> {d};\n", .{ shift_rhs, shift_rhs });
return local;
},
}
}
fn airBoolToInt(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const un_op = f.air.instructions.items(.data)[inst].un_op;
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const operand = try f.resolveInst(un_op);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
return local;
}
fn airStoreUndefined(f: *Function, dest_ptr: CValue) !CValue {
const is_debug_build = f.object.dg.module.optimizeMode() == .Debug;
if (!is_debug_build)
return CValue.none;
const writer = f.object.writer();
try writer.writeAll("memset(");
try f.writeCValue(writer, dest_ptr);
try writer.writeAll(", 0xaa, sizeof(");
try f.writeCValueDeref(writer, dest_ptr);
try writer.writeAll("));\n");
return CValue.none;
}
fn airStore(f: *Function, inst: Air.Inst.Index) !CValue {
// *a = b;
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const dest_ptr = try f.resolveInst(bin_op.lhs);
const src_val = try f.resolveInst(bin_op.rhs);
const lhs_child_type = f.air.typeOf(bin_op.lhs).childType();
// TODO Sema should emit a different instruction when the store should
// possibly do the safety 0xaa bytes for undefined.
const src_val_is_undefined =
if (f.air.value(bin_op.rhs)) |v| v.isUndefDeep() else false;
if (src_val_is_undefined)
return try airStoreUndefined(f, dest_ptr);
const writer = f.object.writer();
if (lhs_child_type.zigTypeTag() == .Array) {
// For this memcpy to safely work we need the rhs to have the same
// underlying type as the lhs (i.e. they must both be arrays of the same underlying type).
const rhs_type = f.air.typeOf(bin_op.rhs);
assert(rhs_type.eql(lhs_child_type, f.object.dg.module));
// If the source is a constant, writeCValue will emit a brace initialization
// so work around this by initializing into new local.
// TODO this should be done by manually initializing elements of the dest array
const array_src = if (src_val == .constant) blk: {
const new_local = try f.allocLocal(rhs_type, .Const);
try writer.writeAll(" = ");
try f.writeCValue(writer, src_val);
try writer.writeAll(";");
try f.object.indent_writer.insertNewline();
break :blk new_local;
} else src_val;
try writer.writeAll("memcpy(");
try f.writeCValue(writer, dest_ptr);
try writer.writeAll(", ");
try f.writeCValue(writer, array_src);
try writer.writeAll(", sizeof(");
try f.writeCValue(writer, array_src);
try writer.writeAll("));\n");
} else {
try f.writeCValueDeref(writer, dest_ptr);
try writer.writeAll(" = ");
try f.writeCValue(writer, src_val);
try writer.writeAll(";\n");
}
return CValue.none;
}
fn airWrapOp(
f: *Function,
inst: Air.Inst.Index,
str_op: [*:0]const u8,
fn_op: [*:0]const u8,
) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const inst_ty = f.air.typeOfIndex(inst);
const target = f.object.dg.module.getTarget();
const int_info = inst_ty.intInfo(target);
const bits = int_info.bits;
// if it's an unsigned int with non-arbitrary bit size then we can just add
if (int_info.signedness == .unsigned) {
const ok_bits = switch (bits) {
8, 16, 32, 64, 128 => true,
else => false,
};
if (ok_bits or inst_ty.tag() != .int_unsigned) {
return try airBinOp(f, inst, str_op);
}
}
if (bits > 64) {
return f.fail("TODO: C backend: airWrapOp for large integers", .{});
}
var max_buf: [80]u8 = undefined;
const max = intMax(inst_ty, target, &max_buf);
const lhs = try f.resolveInst(bin_op.lhs);
const rhs = try f.resolveInst(bin_op.rhs);
const w = f.object.writer();
const ret = try f.allocLocal(inst_ty, .Mut);
try w.print(" = zig_{s}", .{fn_op});
switch (inst_ty.tag()) {
.isize => try w.writeAll("isize"),
.c_short => try w.writeAll("short"),
.c_int => try w.writeAll("int"),
.c_long => try w.writeAll("long"),
.c_longlong => try w.writeAll("longlong"),
else => {
const prefix_byte: u8 = signAbbrev(int_info.signedness);
for ([_]u8{ 8, 16, 32, 64 }) |nbits| {
if (bits <= nbits) {
try w.print("{c}{d}", .{ prefix_byte, nbits });
break;
}
} else {
unreachable;
}
},
}
try w.writeByte('(');
try f.writeCValue(w, lhs);
try w.writeAll(", ");
try f.writeCValue(w, rhs);
if (int_info.signedness == .signed) {
var min_buf: [80]u8 = undefined;
const min = intMin(inst_ty, target, &min_buf);
try w.print(", {s}", .{min});
}
try w.print(", {s});", .{max});
try f.object.indent_writer.insertNewline();
return ret;
}
fn airSatOp(f: *Function, inst: Air.Inst.Index, fn_op: [*:0]const u8) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const inst_ty = f.air.typeOfIndex(inst);
const int_info = inst_ty.intInfo(f.object.dg.module.getTarget());
const bits = int_info.bits;
switch (bits) {
8, 16, 32, 64, 128 => {},
else => return f.object.dg.fail("TODO: C backend: airSatOp for non power of 2 integers", .{}),
}
// if it's an unsigned int with non-arbitrary bit size then we can just add
if (bits > 64) {
return f.object.dg.fail("TODO: C backend: airSatOp for large integers", .{});
}
var min_buf: [80]u8 = undefined;
const min = switch (int_info.signedness) {
.unsigned => "0",
else => switch (inst_ty.tag()) {
.c_short => "SHRT_MIN",
.c_int => "INT_MIN",
.c_long => "LONG_MIN",
.c_longlong => "LLONG_MIN",
.isize => "INTPTR_MIN",
else => blk: {
// compute the type minimum based on the bitcount (bits)
const val = -1 * std.math.pow(i65, 2, @intCast(i65, bits - 1));
break :blk std.fmt.bufPrint(&min_buf, "{d}", .{val}) catch |err| switch (err) {
error.NoSpaceLeft => unreachable,
};
},
},
};
var max_buf: [80]u8 = undefined;
const max = switch (inst_ty.tag()) {
.c_short => "SHRT_MAX",
.c_ushort => "USHRT_MAX",
.c_int => "INT_MAX",
.c_uint => "UINT_MAX",
.c_long => "LONG_MAX",
.c_ulong => "ULONG_MAX",
.c_longlong => "LLONG_MAX",
.c_ulonglong => "ULLONG_MAX",
.isize => "INTPTR_MAX",
.usize => "UINTPTR_MAX",
else => blk: {
const pow_bits = switch (int_info.signedness) {
.signed => bits - 1,
.unsigned => bits,
};
const val = std.math.pow(u65, 2, pow_bits) - 1;
break :blk std.fmt.bufPrint(&max_buf, "{}", .{val}) catch |err| switch (err) {
error.NoSpaceLeft => unreachable,
};
},
};
const lhs = try f.resolveInst(bin_op.lhs);
const rhs = try f.resolveInst(bin_op.rhs);
const w = f.object.writer();
const ret = try f.allocLocal(inst_ty, .Mut);
try w.print(" = zig_{s}", .{fn_op});
switch (inst_ty.tag()) {
.isize => try w.writeAll("isize"),
.c_short => try w.writeAll("short"),
.c_int => try w.writeAll("int"),
.c_long => try w.writeAll("long"),
.c_longlong => try w.writeAll("longlong"),
else => {
const prefix_byte: u8 = signAbbrev(int_info.signedness);
for ([_]u8{ 8, 16, 32, 64 }) |nbits| {
if (bits <= nbits) {
try w.print("{c}{d}", .{ prefix_byte, nbits });
break;
}
} else {
unreachable;
}
},
}
try w.writeByte('(');
try f.writeCValue(w, lhs);
try w.writeAll(", ");
try f.writeCValue(w, rhs);
if (int_info.signedness == .signed) {
try w.print(", {s}", .{min});
}
try w.print(", {s});", .{max});
try f.object.indent_writer.insertNewline();
return ret;
}
fn airOverflow(f: *Function, inst: Air.Inst.Index, op_abbrev: [*:0]const u8) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const bin_op = f.air.extraData(Air.Bin, ty_pl.payload).data;
const lhs = try f.resolveInst(bin_op.lhs);
const rhs = try f.resolveInst(bin_op.rhs);
const inst_ty = f.air.typeOfIndex(inst);
const scalar_ty = f.air.typeOf(bin_op.lhs).scalarType();
const target = f.object.dg.module.getTarget();
const int_info = scalar_ty.intInfo(target);
const w = f.object.writer();
const c_bits = toCIntBits(int_info.bits) orelse
return f.fail("TODO: C backend: implement integer arithmetic larger than 128 bits", .{});
var max_buf: [80]u8 = undefined;
const max = intMax(scalar_ty, target, &max_buf);
const ret = try f.allocLocal(inst_ty, .Mut);
try w.writeAll(";");
try f.object.indent_writer.insertNewline();
try f.writeCValue(w, ret);
switch (int_info.signedness) {
.unsigned => {
try w.print(".field_1 = zig_{s}u{d}(", .{
op_abbrev, c_bits,
});
try f.writeCValue(w, lhs);
try w.writeAll(", ");
try f.writeCValue(w, rhs);
try w.writeAll(", &");
try f.writeCValue(w, ret);
try w.print(".field_0, {s}", .{max});
},
.signed => {
var min_buf: [80]u8 = undefined;
const min = intMin(scalar_ty, target, &min_buf);
try w.print(".field_1 = zig_{s}i{d}(", .{
op_abbrev, c_bits,
});
try f.writeCValue(w, lhs);
try w.writeAll(", ");
try f.writeCValue(w, rhs);
try w.writeAll(", &");
try f.writeCValue(w, ret);
try w.print(".field_0, {s}, {s}", .{ min, max });
},
}
try w.writeAll(");");
try f.object.indent_writer.insertNewline();
return ret;
}
fn airNot(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const op = try f.resolveInst(ty_op.operand);
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
if (inst_ty.zigTypeTag() == .Bool)
try writer.writeAll("!")
else
try writer.writeAll("~");
try f.writeCValue(writer, op);
try writer.writeAll(";\n");
return local;
}
fn airBinOp(f: *Function, inst: Air.Inst.Index, operator: [*:0]const u8) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const lhs = try f.resolveInst(bin_op.lhs);
const rhs = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
try f.writeCValue(writer, lhs);
try writer.print("{s}", .{operator});
try f.writeCValue(writer, rhs);
try writer.writeAll(";\n");
return local;
}
fn airEquality(
f: *Function,
inst: Air.Inst.Index,
negate_prefix: []const u8,
eq_op_str: []const u8,
) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const lhs = try f.resolveInst(bin_op.lhs);
const rhs = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
const lhs_ty = f.air.typeOf(bin_op.lhs);
if (lhs_ty.tag() == .optional) {
// (A && B) || (C && (A == B))
// A = lhs.is_null ; B = rhs.is_null ; C = rhs.payload == lhs.payload
try writer.writeAll(negate_prefix);
try f.writeCValue(writer, lhs);
try writer.writeAll(".is_null && ");
try f.writeCValue(writer, rhs);
try writer.writeAll(".is_null) || (");
try f.writeCValue(writer, lhs);
try writer.writeAll(".payload == ");
try f.writeCValue(writer, rhs);
try writer.writeAll(".payload && ");
try f.writeCValue(writer, lhs);
try writer.writeAll(".is_null == ");
try f.writeCValue(writer, rhs);
try writer.writeAll(".is_null));\n");
return local;
}
try f.writeCValue(writer, lhs);
try writer.writeAll(eq_op_str);
try f.writeCValue(writer, rhs);
try writer.writeAll(";\n");
return local;
}
fn airPtrAddSub(f: *Function, inst: Air.Inst.Index, operator: [*:0]const u8) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const bin_op = f.air.extraData(Air.Bin, ty_pl.payload).data;
const lhs = try f.resolveInst(bin_op.lhs);
const rhs = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const elem_ty = switch (inst_ty.ptrSize()) {
.One => blk: {
const array_ty = inst_ty.childType();
break :blk array_ty.childType();
},
else => inst_ty.childType(),
};
// We must convert to and from integer types to prevent UB if the operation results in a NULL pointer,
// or if LHS is NULL. The operation is only UB if the result is NULL and then dereferenced.
try writer.writeAll(" = (");
try f.renderTypecast(writer, inst_ty);
try writer.writeAll(")(((uintptr_t)");
try f.writeCValue(writer, lhs);
try writer.print("){s}(", .{operator});
try f.writeCValue(writer, rhs);
try writer.writeAll("*sizeof(");
try f.renderTypecast(writer, elem_ty);
try writer.print(")));\n", .{});
return local;
}
fn airMinMax(f: *Function, inst: Air.Inst.Index, operator: [*:0]const u8) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const lhs = try f.resolveInst(bin_op.lhs);
const rhs = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
// (lhs <> rhs) ? lhs : rhs
try writer.writeAll(" = (");
try f.writeCValue(writer, lhs);
try writer.print("{s}", .{operator});
try f.writeCValue(writer, rhs);
try writer.writeAll(") ? ");
try f.writeCValue(writer, lhs);
try writer.writeAll(" : ");
try f.writeCValue(writer, rhs);
try writer.writeAll(";\n");
return local;
}
fn airSlice(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const bin_op = f.air.extraData(Air.Bin, ty_pl.payload).data;
const ptr = try f.resolveInst(bin_op.lhs);
const len = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = {");
try f.writeCValue(writer, ptr);
try writer.writeAll(", ");
try f.writeCValue(writer, len);
try writer.writeAll("};\n");
return local;
}
fn airCall(
f: *Function,
inst: Air.Inst.Index,
modifier: std.builtin.CallOptions.Modifier,
) !CValue {
switch (modifier) {
.auto => {},
.always_tail => return f.fail("TODO: C backend: call with always_tail attribute", .{}),
.never_tail => return f.fail("TODO: C backend: call with never_tail attribute", .{}),
.never_inline => return f.fail("TODO: C backend: call with never_inline attribute", .{}),
else => unreachable,
}
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const extra = f.air.extraData(Air.Call, pl_op.payload);
const args = @ptrCast([]const Air.Inst.Ref, f.air.extra[extra.end..][0..extra.data.args_len]);
const callee_ty = f.air.typeOf(pl_op.operand);
const fn_ty = switch (callee_ty.zigTypeTag()) {
.Fn => callee_ty,
.Pointer => callee_ty.childType(),
else => unreachable,
};
const writer = f.object.writer();
const result_local: CValue = r: {
if (f.liveness.isUnused(inst)) {
if (loweredFnRetTyHasBits(fn_ty)) {
try writer.print("(void)", .{});
}
break :r .none;
} else {
const local = try f.allocLocal(fn_ty.fnReturnType(), .Const);
try writer.writeAll(" = ");
break :r local;
}
};
callee: {
known: {
const fn_decl = fn_decl: {
const callee_val = f.air.value(pl_op.operand) orelse break :known;
break :fn_decl switch (callee_val.tag()) {
.extern_fn => callee_val.castTag(.extern_fn).?.data.owner_decl,
.function => callee_val.castTag(.function).?.data.owner_decl,
.decl_ref => callee_val.castTag(.decl_ref).?.data,
else => break :known,
};
};
try f.object.dg.renderDeclName(writer, fn_decl);
break :callee;
}
// Fall back to function pointer call.
const callee = try f.resolveInst(pl_op.operand);
try f.writeCValue(writer, callee);
}
try writer.writeAll("(");
var args_written: usize = 0;
for (args) |arg| {
const ty = f.air.typeOf(arg);
if (!ty.hasRuntimeBitsIgnoreComptime()) continue;
if (args_written != 0) {
try writer.writeAll(", ");
}
if (f.air.value(arg)) |val| {
try f.object.dg.renderValue(writer, f.air.typeOf(arg), val, .FunctionArgument);
} else {
const val = try f.resolveInst(arg);
try f.writeCValue(writer, val);
}
args_written += 1;
}
try writer.writeAll(");\n");
return result_local;
}
fn airDbgStmt(f: *Function, inst: Air.Inst.Index) !CValue {
const dbg_stmt = f.air.instructions.items(.data)[inst].dbg_stmt;
const writer = f.object.writer();
// TODO re-evaluate whether to emit these or not. If we naively emit
// these directives, the output file will report bogus line numbers because
// every newline after the #line directive adds one to the line.
// We also don't print the filename yet, so the output is strictly unhelpful.
// If we wanted to go this route, we would need to go all the way and not output
// newlines until the next dbg_stmt occurs.
// Perhaps an additional compilation option is in order?
//try writer.print("#line {d}\n", .{dbg_stmt.line + 1});
try writer.print("/* file:{d}:{d} */\n", .{ dbg_stmt.line + 1, dbg_stmt.column + 1 });
return CValue.none;
}
fn airDbgInline(f: *Function, inst: Air.Inst.Index) !CValue {
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const writer = f.object.writer();
const function = f.air.values[ty_pl.payload].castTag(.function).?.data;
const mod = f.object.dg.module;
try writer.print("/* dbg func:{s} */\n", .{mod.declPtr(function.owner_decl).name});
return CValue.none;
}
fn airDbgVar(f: *Function, inst: Air.Inst.Index) !CValue {
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const name = f.air.nullTerminatedString(pl_op.payload);
const operand = try f.resolveInst(pl_op.operand);
_ = operand;
const writer = f.object.writer();
try writer.print("/* var:{s} */\n", .{name});
return CValue.none;
}
fn airBlock(f: *Function, inst: Air.Inst.Index) !CValue {
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const extra = f.air.extraData(Air.Block, ty_pl.payload);
const body = f.air.extra[extra.end..][0..extra.data.body_len];
const block_id: usize = f.next_block_index;
f.next_block_index += 1;
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const result = if (inst_ty.tag() != .void and !f.liveness.isUnused(inst)) blk: {
// allocate a location for the result
const local = try f.allocLocal(inst_ty, .Mut);
try writer.writeAll(";\n");
break :blk local;
} else CValue{ .none = {} };
try f.blocks.putNoClobber(f.object.dg.gpa, inst, .{
.block_id = block_id,
.result = result,
});
try genBody(f, body);
try f.object.indent_writer.insertNewline();
// label must be followed by an expression, add an empty one.
try writer.print("zig_block_{d}:;\n", .{block_id});
return result;
}
fn airTry(f: *Function, inst: Air.Inst.Index) !CValue {
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const err_union = try f.resolveInst(pl_op.operand);
const extra = f.air.extraData(Air.Try, pl_op.payload);
const body = f.air.extra[extra.end..][0..extra.data.body_len];
const err_union_ty = f.air.typeOf(pl_op.operand);
const result_ty = f.air.typeOfIndex(inst);
return lowerTry(f, err_union, body, err_union_ty, false, result_ty);
}
fn airTryPtr(f: *Function, inst: Air.Inst.Index) !CValue {
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const extra = f.air.extraData(Air.TryPtr, ty_pl.payload);
const err_union_ptr = try f.resolveInst(extra.data.ptr);
const body = f.air.extra[extra.end..][0..extra.data.body_len];
const err_union_ty = f.air.typeOf(extra.data.ptr).childType();
const result_ty = f.air.typeOfIndex(inst);
return lowerTry(f, err_union_ptr, body, err_union_ty, true, result_ty);
}
fn lowerTry(
f: *Function,
err_union: CValue,
body: []const Air.Inst.Index,
err_union_ty: Type,
operand_is_ptr: bool,
result_ty: Type,
) !CValue {
const writer = f.object.writer();
const payload_ty = err_union_ty.errorUnionPayload();
const payload_has_bits = payload_ty.hasRuntimeBitsIgnoreComptime();
if (!err_union_ty.errorUnionSet().errorSetIsEmpty()) {
err: {
if (!payload_has_bits) {
if (operand_is_ptr) {
try writer.writeAll("if(*");
} else {
try writer.writeAll("if(");
}
try f.writeCValue(writer, err_union);
try writer.writeAll(")");
break :err;
}
if (operand_is_ptr or isByRef(err_union_ty)) {
try writer.writeAll("if(");
try f.writeCValue(writer, err_union);
try writer.writeAll("->error)");
break :err;
}
try writer.writeAll("if(");
try f.writeCValue(writer, err_union);
try writer.writeAll(".error)");
}
try genBody(f, body);
try f.object.indent_writer.insertNewline();
}
if (!payload_has_bits) {
if (!operand_is_ptr) {
return CValue.none;
} else {
return err_union;
}
}
const local = try f.allocLocal(result_ty, .Const);
if (operand_is_ptr or isByRef(payload_ty)) {
try writer.writeAll(" = &");
try f.writeCValue(writer, err_union);
try writer.writeAll("->payload;\n");
} else {
try writer.writeAll(" = ");
try f.writeCValue(writer, err_union);
try writer.writeAll(".payload;\n");
}
return local;
}
fn airBr(f: *Function, inst: Air.Inst.Index) !CValue {
const branch = f.air.instructions.items(.data)[inst].br;
const block = f.blocks.get(branch.block_inst).?;
const result = block.result;
const writer = f.object.writer();
// If result is .none then the value of the block is unused.
if (result != .none) {
const operand = try f.resolveInst(branch.operand);
try f.writeCValue(writer, result);
try writer.writeAll(" = ");
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
}
try f.object.writer().print("goto zig_block_{d};\n", .{block.block_id});
return CValue.none;
}
fn airBitcast(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const operand = try f.resolveInst(ty_op.operand);
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
if (inst_ty.isPtrAtRuntime() and
f.air.typeOf(ty_op.operand).isPtrAtRuntime())
{
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = (");
try f.renderTypecast(writer, inst_ty);
try writer.writeAll(")");
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
return local;
}
const local = try f.allocLocal(inst_ty, .Mut);
try writer.writeAll(";\n");
try writer.writeAll("memcpy(&");
try f.writeCValue(writer, local);
try writer.writeAll(", &");
try f.writeCValue(writer, operand);
try writer.writeAll(", sizeof(");
try f.writeCValue(writer, local);
try writer.writeAll("));\n");
return local;
}
fn airBreakpoint(f: *Function) !CValue {
try f.object.writer().writeAll("zig_breakpoint();\n");
return CValue.none;
}
fn airRetAddr(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const local = try f.allocLocal(Type.usize, .Const);
try f.object.writer().writeAll(" = zig_return_address();\n");
return local;
}
fn airFrameAddress(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const local = try f.allocLocal(Type.usize, .Const);
try f.object.writer().writeAll(" = zig_frame_address();\n");
return local;
}
fn airFence(f: *Function, inst: Air.Inst.Index) !CValue {
const atomic_order = f.air.instructions.items(.data)[inst].fence;
const writer = f.object.writer();
try writer.writeAll("zig_fence(");
try writeMemoryOrder(writer, atomic_order);
try writer.writeAll(");\n");
return CValue.none;
}
fn airUnreach(f: *Function) !CValue {
try f.object.writer().writeAll("zig_unreachable();\n");
return CValue.none;
}
fn airLoop(f: *Function, inst: Air.Inst.Index) !CValue {
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const loop = f.air.extraData(Air.Block, ty_pl.payload);
const body = f.air.extra[loop.end..][0..loop.data.body_len];
try f.object.writer().writeAll("while (true) ");
try genBody(f, body);
try f.object.indent_writer.insertNewline();
return CValue.none;
}
fn airCondBr(f: *Function, inst: Air.Inst.Index) !CValue {
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const cond = try f.resolveInst(pl_op.operand);
const extra = f.air.extraData(Air.CondBr, pl_op.payload);
const then_body = f.air.extra[extra.end..][0..extra.data.then_body_len];
const else_body = f.air.extra[extra.end + then_body.len ..][0..extra.data.else_body_len];
const writer = f.object.writer();
try writer.writeAll("if (");
try f.writeCValue(writer, cond);
try writer.writeAll(") ");
try genBody(f, then_body);
try writer.writeAll(" else ");
try genBody(f, else_body);
try f.object.indent_writer.insertNewline();
return CValue.none;
}
fn airSwitchBr(f: *Function, inst: Air.Inst.Index) !CValue {
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const condition = try f.resolveInst(pl_op.operand);
const condition_ty = f.air.typeOf(pl_op.operand);
const switch_br = f.air.extraData(Air.SwitchBr, pl_op.payload);
const writer = f.object.writer();
try writer.writeAll("switch (");
try f.writeCValue(writer, condition);
try writer.writeAll(") {");
f.object.indent_writer.pushIndent();
var extra_index: usize = switch_br.end;
var case_i: u32 = 0;
while (case_i < switch_br.data.cases_len) : (case_i += 1) {
const case = f.air.extraData(Air.SwitchBr.Case, extra_index);
const items = @ptrCast([]const Air.Inst.Ref, f.air.extra[case.end..][0..case.data.items_len]);
const case_body = f.air.extra[case.end + items.len ..][0..case.data.body_len];
extra_index = case.end + case.data.items_len + case_body.len;
for (items) |item| {
try f.object.indent_writer.insertNewline();
try writer.writeAll("case ");
try f.object.dg.renderValue(writer, condition_ty, f.air.value(item).?, .Other);
try writer.writeAll(": ");
}
// The case body must be noreturn so we don't need to insert a break.
try genBody(f, case_body);
}
const else_body = f.air.extra[extra_index..][0..switch_br.data.else_body_len];
try f.object.indent_writer.insertNewline();
try writer.writeAll("default: ");
try genBody(f, else_body);
try f.object.indent_writer.insertNewline();
f.object.indent_writer.popIndent();
try writer.writeAll("}\n");
return CValue.none;
}
fn airAsm(f: *Function, inst: Air.Inst.Index) !CValue {
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const extra = f.air.extraData(Air.Asm, ty_pl.payload);
const is_volatile = @truncate(u1, extra.data.flags >> 31) != 0;
const clobbers_len = @truncate(u31, extra.data.flags);
var extra_i: usize = extra.end;
const outputs = @ptrCast([]const Air.Inst.Ref, f.air.extra[extra_i..][0..extra.data.outputs_len]);
extra_i += outputs.len;
const inputs = @ptrCast([]const Air.Inst.Ref, f.air.extra[extra_i..][0..extra.data.inputs_len]);
extra_i += inputs.len;
if (!is_volatile and f.liveness.isUnused(inst)) return CValue.none;
if (outputs.len > 1) {
return f.fail("TODO implement codegen for asm with more than 1 output", .{});
}
const output_constraint: ?[]const u8 = for (outputs) |output| {
if (output != .none) {
return f.fail("TODO implement codegen for non-expr asm", .{});
}
const extra_bytes = std.mem.sliceAsBytes(f.air.extra[extra_i..]);
const constraint = std.mem.sliceTo(std.mem.sliceAsBytes(f.air.extra[extra_i..]), 0);
const name = std.mem.sliceTo(extra_bytes[constraint.len + 1 ..], 0);
// This equation accounts for the fact that even if we have exactly 4 bytes
// for the string, we still use the next u32 for the null terminator.
extra_i += (constraint.len + name.len + (2 + 3)) / 4;
break constraint;
} else null;
const writer = f.object.writer();
try writer.writeAll("{\n");
const inputs_extra_begin = extra_i;
for (inputs) |input, i| {
const input_bytes = std.mem.sliceAsBytes(f.air.extra[extra_i..]);
const constraint = std.mem.sliceTo(input_bytes, 0);
const name = std.mem.sliceTo(input_bytes[constraint.len + 1 ..], 0);
// This equation accounts for the fact that even if we have exactly 4 bytes
// for the string, we still use the next u32 for the null terminator.
extra_i += (constraint.len + name.len + (2 + 3)) / 4;
if (constraint[0] == '{' and constraint[constraint.len - 1] == '}') {
const reg = constraint[1 .. constraint.len - 1];
const arg_c_value = try f.resolveInst(input);
try writer.writeAll("register ");
try f.renderType(writer, f.air.typeOf(input));
try writer.print(" {s}_constant __asm__(\"{s}\") = ", .{ reg, reg });
try f.writeCValue(writer, arg_c_value);
try writer.writeAll(";\n");
} else {
try writer.writeAll("register ");
try f.renderType(writer, f.air.typeOf(input));
try writer.print(" input_{d} = ", .{i});
try f.writeCValue(writer, try f.resolveInst(input));
try writer.writeAll(";\n");
}
}
{
var clobber_i: u32 = 0;
while (clobber_i < clobbers_len) : (clobber_i += 1) {
const clobber = std.mem.sliceTo(std.mem.sliceAsBytes(f.air.extra[extra_i..]), 0);
// This equation accounts for the fact that even if we have exactly 4 bytes
// for the string, we still use the next u32 for the null terminator.
extra_i += clobber.len / 4 + 1;
// TODO honor these
}
}
const asm_source = std.mem.sliceAsBytes(f.air.extra[extra_i..])[0..extra.data.source_len];
const volatile_string: []const u8 = if (is_volatile) "volatile " else "";
try writer.print("__asm {s}(\"{s}\"", .{ volatile_string, asm_source });
if (output_constraint) |_| {
return f.fail("TODO: CBE inline asm output", .{});
}
if (inputs.len > 0) {
if (output_constraint == null) {
try writer.writeAll(" :");
}
try writer.writeAll(": ");
extra_i = inputs_extra_begin;
for (inputs) |_, index| {
const constraint = std.mem.sliceTo(std.mem.sliceAsBytes(f.air.extra[extra_i..]), 0);
// This equation accounts for the fact that even if we have exactly 4 bytes
// for the string, we still use the next u32 for the null terminator.
extra_i += constraint.len / 4 + 1;
if (constraint[0] == '{' and constraint[constraint.len - 1] == '}') {
const reg = constraint[1 .. constraint.len - 1];
if (index > 0) {
try writer.writeAll(", ");
}
try writer.print("\"r\"({s}_constant)", .{reg});
} else {
if (index > 0) {
try writer.writeAll(", ");
}
try writer.print("\"r\"(input_{d})", .{index});
}
}
}
try writer.writeAll(");\n");
try writer.writeAll("}\n");
if (f.liveness.isUnused(inst))
return CValue.none;
return f.fail("TODO: C backend: inline asm expression result used", .{});
}
fn airIsNull(
f: *Function,
inst: Air.Inst.Index,
operator: [*:0]const u8,
deref_suffix: [*:0]const u8,
) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const un_op = f.air.instructions.items(.data)[inst].un_op;
const writer = f.object.writer();
const operand = try f.resolveInst(un_op);
const local = try f.allocLocal(Type.initTag(.bool), .Const);
try writer.writeAll(" = (");
try f.writeCValue(writer, operand);
const ty = f.air.typeOf(un_op);
var opt_buf: Type.Payload.ElemType = undefined;
const payload_ty = if (deref_suffix[0] != 0)
ty.childType().optionalChild(&opt_buf)
else
ty.optionalChild(&opt_buf);
if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
try writer.print("){s} {s} true;\n", .{ deref_suffix, operator });
} else if (ty.isPtrLikeOptional()) {
// operand is a regular pointer, test `operand !=/== NULL`
try writer.print("){s} {s} NULL;\n", .{ deref_suffix, operator });
} else if (payload_ty.zigTypeTag() == .ErrorSet) {
try writer.print("){s} {s} 0;\n", .{ deref_suffix, operator });
} else {
try writer.print("){s}.is_null {s} true;\n", .{ deref_suffix, operator });
}
return local;
}
fn airOptionalPayload(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const opt_ty = f.air.typeOf(ty_op.operand);
var buf: Type.Payload.ElemType = undefined;
const payload_ty = opt_ty.optionalChild(&buf);
if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
return CValue.none;
}
if (opt_ty.optionalReprIsPayload()) {
return operand;
}
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = (");
try f.writeCValue(writer, operand);
try writer.writeAll(").payload;\n");
return local;
}
fn airOptionalPayloadPtr(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const ptr_ty = f.air.typeOf(ty_op.operand);
const opt_ty = ptr_ty.childType();
var buf: Type.Payload.ElemType = undefined;
const payload_ty = opt_ty.optionalChild(&buf);
if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
return operand;
}
if (opt_ty.optionalReprIsPayload()) {
// the operand is just a regular pointer, no need to do anything special.
// *?*T -> **T and ?*T -> *T are **T -> **T and *T -> *T in C
return operand;
}
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = &(");
try f.writeCValue(writer, operand);
try writer.writeAll(")->payload;\n");
return local;
}
fn airOptionalPayloadPtrSet(f: *Function, inst: Air.Inst.Index) !CValue {
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const operand_ty = f.air.typeOf(ty_op.operand);
const opt_ty = operand_ty.elemType();
if (opt_ty.optionalReprIsPayload()) {
// The payload and the optional are the same value.
// Setting to non-null will be done when the payload is set.
return operand;
}
try f.writeCValueDeref(writer, operand);
try writer.writeAll(".is_null = false;\n");
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = &");
try f.writeCValueDeref(writer, operand);
try writer.writeAll(".payload;\n");
return local;
}
fn airStructFieldPtr(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
// TODO this @as is needed because of a stage1 bug
return @as(CValue, CValue.none);
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const extra = f.air.extraData(Air.StructField, ty_pl.payload).data;
const struct_ptr = try f.resolveInst(extra.struct_operand);
const struct_ptr_ty = f.air.typeOf(extra.struct_operand);
return structFieldPtr(f, inst, struct_ptr_ty, struct_ptr, extra.field_index);
}
fn airStructFieldPtrIndex(f: *Function, inst: Air.Inst.Index, index: u8) !CValue {
if (f.liveness.isUnused(inst))
// TODO this @as is needed because of a stage1 bug
return @as(CValue, CValue.none);
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const struct_ptr = try f.resolveInst(ty_op.operand);
const struct_ptr_ty = f.air.typeOf(ty_op.operand);
return structFieldPtr(f, inst, struct_ptr_ty, struct_ptr, index);
}
fn airFieldParentPtr(f: *Function, inst: Air.Inst.Index) !CValue {
_ = inst;
return f.fail("TODO: C backend: implement airFieldParentPtr", .{});
}
fn structFieldPtr(f: *Function, inst: Air.Inst.Index, struct_ptr_ty: Type, struct_ptr: CValue, index: u32) !CValue {
const writer = f.object.writer();
const struct_ty = struct_ptr_ty.elemType();
var field_name: []const u8 = undefined;
var field_val_ty: Type = undefined;
var buf = std.ArrayList(u8).init(f.object.dg.gpa);
defer buf.deinit();
switch (struct_ty.tag()) {
.@"struct" => {
const fields = struct_ty.structFields();
field_name = fields.keys()[index];
field_val_ty = fields.values()[index].ty;
},
.@"union", .union_safety_tagged, .union_tagged => {
const fields = struct_ty.unionFields();
field_name = fields.keys()[index];
field_val_ty = fields.values()[index].ty;
},
.tuple, .anon_struct => {
const tuple = struct_ty.tupleFields();
if (tuple.values[index].tag() != .unreachable_value) return CValue.none;
try buf.writer().print("field_{d}", .{index});
field_name = buf.items;
field_val_ty = tuple.types[index];
},
else => unreachable,
}
const payload = if (struct_ty.tag() == .union_tagged or struct_ty.tag() == .union_safety_tagged) "payload." else "";
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
if (field_val_ty.hasRuntimeBitsIgnoreComptime()) {
try writer.writeAll(" = &");
try f.writeCValueDeref(writer, struct_ptr);
try writer.print(".{s}{ };\n", .{ payload, fmtIdent(field_name) });
} else {
try writer.writeAll(" = (");
try f.renderTypecast(writer, inst_ty);
try writer.writeByte(')');
try f.writeCValue(writer, struct_ptr);
try writer.writeAll(";\n");
}
return local;
}
fn airStructFieldVal(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const extra = f.air.extraData(Air.StructField, ty_pl.payload).data;
const writer = f.object.writer();
const struct_byval = try f.resolveInst(extra.struct_operand);
const struct_ty = f.air.typeOf(extra.struct_operand);
var buf = std.ArrayList(u8).init(f.object.dg.gpa);
defer buf.deinit();
const field_name = switch (struct_ty.tag()) {
.@"struct" => struct_ty.structFields().keys()[extra.field_index],
.@"union", .union_safety_tagged, .union_tagged => struct_ty.unionFields().keys()[extra.field_index],
.tuple, .anon_struct => blk: {
const tuple = struct_ty.tupleFields();
if (tuple.values[extra.field_index].tag() != .unreachable_value) return CValue.none;
try buf.writer().print("field_{d}", .{extra.field_index});
break :blk buf.items;
},
else => unreachable,
};
const payload = if (struct_ty.tag() == .union_tagged or struct_ty.tag() == .union_safety_tagged) "payload." else "";
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
try f.writeCValue(writer, struct_byval);
try writer.print(".{s}{ };\n", .{ payload, fmtIdent(field_name) });
return local;
}
/// *(E!T) -> E
/// Note that the result is never a pointer.
fn airUnwrapErrUnionErr(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const inst_ty = f.air.typeOfIndex(inst);
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const operand_ty = f.air.typeOf(ty_op.operand);
if (operand_ty.zigTypeTag() == .Pointer) {
const err_union_ty = operand_ty.childType();
if (err_union_ty.errorUnionSet().errorSetIsEmpty()) {
return CValue{ .bytes = "0" };
}
if (!err_union_ty.errorUnionPayload().hasRuntimeBits()) {
return operand;
}
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = *");
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
return local;
}
if (operand_ty.errorUnionSet().errorSetIsEmpty()) {
return CValue{ .bytes = "0" };
}
if (!operand_ty.errorUnionPayload().hasRuntimeBits()) {
return operand;
}
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
if (operand_ty.zigTypeTag() == .Pointer) {
try f.writeCValueDeref(writer, operand);
} else {
try f.writeCValue(writer, operand);
}
try writer.writeAll(".error;\n");
return local;
}
fn airUnwrapErrUnionPay(f: *Function, inst: Air.Inst.Index, maybe_addrof: [*:0]const u8) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const operand_ty = f.air.typeOf(ty_op.operand);
const operand_is_ptr = operand_ty.zigTypeTag() == .Pointer;
const error_union_ty = if (operand_is_ptr) operand_ty.childType() else operand_ty;
if (!error_union_ty.errorUnionPayload().hasRuntimeBits()) {
return CValue.none;
}
const inst_ty = f.air.typeOfIndex(inst);
const maybe_deref = if (operand_is_ptr) "->" else ".";
const local = try f.allocLocal(inst_ty, .Const);
try writer.print(" = {s}(", .{maybe_addrof});
try f.writeCValue(writer, operand);
try writer.print("){s}payload;\n", .{maybe_deref});
return local;
}
fn airWrapOptional(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const inst_ty = f.air.typeOfIndex(inst);
if (inst_ty.optionalReprIsPayload()) {
return operand;
}
// .wrap_optional is used to convert non-optionals into optionals so it can never be null.
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = { .is_null = false, .payload =");
try f.writeCValue(writer, operand);
try writer.writeAll("};\n");
return local;
}
fn airWrapErrUnionErr(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const writer = f.object.writer();
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const operand = try f.resolveInst(ty_op.operand);
const err_un_ty = f.air.typeOfIndex(inst);
const payload_ty = err_un_ty.errorUnionPayload();
if (!payload_ty.hasRuntimeBits()) {
return operand;
}
const local = try f.allocLocal(err_un_ty, .Const);
try writer.writeAll(" = { .error = ");
try f.writeCValue(writer, operand);
try writer.writeAll(" };\n");
return local;
}
fn airErrUnionPayloadPtrSet(f: *Function, inst: Air.Inst.Index) !CValue {
const writer = f.object.writer();
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const operand = try f.resolveInst(ty_op.operand);
const error_union_ty = f.air.typeOf(ty_op.operand).childType();
const error_ty = error_union_ty.errorUnionSet();
const payload_ty = error_union_ty.errorUnionPayload();
// First, set the non-error value.
if (!payload_ty.hasRuntimeBitsIgnoreComptime()) {
try f.writeCValueDeref(writer, operand);
try writer.writeAll(" = ");
try f.object.dg.renderValue(writer, error_ty, Value.zero, .Other);
try writer.writeAll(";\n ");
return operand;
}
try f.writeCValueDeref(writer, operand);
try writer.writeAll(".error = ");
try f.object.dg.renderValue(writer, error_ty, Value.zero, .Other);
try writer.writeAll(";\n");
// Then return the payload pointer (only if it is used)
if (f.liveness.isUnused(inst)) return CValue.none;
const local = try f.allocLocal(f.air.typeOfIndex(inst), .Const);
try writer.writeAll(" = &(");
try f.writeCValueDeref(writer, operand);
try writer.writeAll(").payload;\n");
return local;
}
fn airErrReturnTrace(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
return f.fail("TODO: C backend: implement airErrReturnTrace", .{});
}
fn airSetErrReturnTrace(f: *Function, inst: Air.Inst.Index) !CValue {
_ = inst;
return f.fail("TODO: C backend: implement airSetErrReturnTrace", .{});
}
fn airWrapErrUnionPay(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = { .error = 0, .payload = ");
try f.writeCValue(writer, operand);
try writer.writeAll(" };\n");
return local;
}
fn airIsErr(
f: *Function,
inst: Air.Inst.Index,
is_ptr: bool,
op_str: [*:0]const u8,
) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const un_op = f.air.instructions.items(.data)[inst].un_op;
const writer = f.object.writer();
const operand = try f.resolveInst(un_op);
const operand_ty = f.air.typeOf(un_op);
const local = try f.allocLocal(Type.initTag(.bool), .Const);
const err_union_ty = if (is_ptr) operand_ty.childType() else operand_ty;
const payload_ty = err_union_ty.errorUnionPayload();
const error_ty = err_union_ty.errorUnionSet();
try writer.writeAll(" = ");
if (error_ty.errorSetIsEmpty()) {
try writer.print("0 {s} 0;\n", .{op_str});
} else {
if (is_ptr) {
try f.writeCValueDeref(writer, operand);
} else {
try f.writeCValue(writer, operand);
}
if (payload_ty.hasRuntimeBits()) {
try writer.writeAll(".error");
}
try writer.print(" {s} 0;\n", .{op_str});
}
return local;
}
fn airArrayToSlice(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const array_len = f.air.typeOf(ty_op.operand).elemType().arrayLen();
try writer.writeAll(" = { .ptr = ");
if (operand == .undefined_ptr) {
// Unfortunately, C does not support any equivalent to
// &(*(void *)p)[0], although LLVM does via GetElementPtr
try f.writeCValue(writer, CValue.undefined_ptr);
} else {
try writer.writeAll("&(");
try f.writeCValueDeref(writer, operand);
try writer.writeAll(")[0]");
}
try writer.print(", .len = {d} }};\n", .{array_len});
return local;
}
/// Emits a local variable with the result type and initializes it
/// with the operand.
fn airSimpleCast(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
try writer.writeAll(" = ");
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
return local;
}
fn airPtrToInt(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const un_op = f.air.instructions.items(.data)[inst].un_op;
const writer = f.object.writer();
const operand = try f.resolveInst(un_op);
try writer.writeAll(" = (");
try f.renderTypecast(writer, inst_ty);
try writer.writeAll(")");
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
return local;
}
fn airBuiltinCall(f: *Function, inst: Air.Inst.Index, fn_name: [*:0]const u8) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const operand = f.air.instructions.items(.data)[inst].ty_op.operand;
const operand_ty = f.air.typeOf(operand);
const target = f.object.dg.module.getTarget();
const writer = f.object.writer();
const int_info = operand_ty.intInfo(target);
const c_bits = toCIntBits(int_info.bits) orelse
return f.fail("TODO: C backend: implement integer types larger than 128 bits", .{});
try writer.print(" = zig_{s}_", .{fn_name});
try writer.print("{c}{d}(", .{ signAbbrev(int_info.signedness), c_bits });
try f.writeCValue(writer, try f.resolveInst(operand));
try writer.print(", {d});\n", .{int_info.bits});
return local;
}
fn airBinOpBuiltinCall(f: *Function, inst: Air.Inst.Index, fn_name: [*:0]const u8) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const lhs_ty = f.air.typeOf(bin_op.lhs);
const target = f.object.dg.module.getTarget();
const writer = f.object.writer();
// For binary operations @TypeOf(lhs)==@TypeOf(rhs), so we only check one.
if (lhs_ty.isInt()) {
const int_info = lhs_ty.intInfo(target);
const c_bits = toCIntBits(int_info.bits) orelse
return f.fail("TODO: C backend: implement integer types larger than 128 bits", .{});
try writer.print(" = zig_{s}_{c}{d}", .{ fn_name, signAbbrev(int_info.signedness), c_bits });
} else if (lhs_ty.isRuntimeFloat()) {
const c_bits = lhs_ty.floatBits(target);
try writer.print(" = zig_{s}_f{d}", .{ fn_name, c_bits });
} else {
return f.fail("TODO: C backend: implement airBinOpBuiltinCall for type {s}", .{@tagName(lhs_ty.tag())});
}
try writer.writeByte('(');
try f.writeCValue(writer, try f.resolveInst(bin_op.lhs));
try writer.writeAll(", ");
try f.writeCValue(writer, try f.resolveInst(bin_op.rhs));
try writer.writeAll(");\n");
return local;
}
fn airCmpxchg(f: *Function, inst: Air.Inst.Index, flavor: [*:0]const u8) !CValue {
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const extra = f.air.extraData(Air.Cmpxchg, ty_pl.payload).data;
const inst_ty = f.air.typeOfIndex(inst);
const ptr = try f.resolveInst(extra.ptr);
const expected_value = try f.resolveInst(extra.expected_value);
const new_value = try f.resolveInst(extra.new_value);
const local = try f.allocLocal(inst_ty, .Const);
const writer = f.object.writer();
try writer.print(" = zig_cmpxchg_{s}(", .{flavor});
try f.writeCValue(writer, ptr);
try writer.writeAll(", ");
try f.writeCValue(writer, expected_value);
try writer.writeAll(", ");
try f.writeCValue(writer, new_value);
try writer.writeAll(", ");
try writeMemoryOrder(writer, extra.successOrder());
try writer.writeAll(", ");
try writeMemoryOrder(writer, extra.failureOrder());
try writer.writeAll(");\n");
return local;
}
fn airAtomicRmw(f: *Function, inst: Air.Inst.Index) !CValue {
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const extra = f.air.extraData(Air.AtomicRmw, pl_op.payload).data;
const inst_ty = f.air.typeOfIndex(inst);
const ptr = try f.resolveInst(pl_op.operand);
const operand = try f.resolveInst(extra.operand);
const local = try f.allocLocal(inst_ty, .Const);
const writer = f.object.writer();
try writer.print(" = zig_atomicrmw_{s}(", .{toAtomicRmwSuffix(extra.op())});
try f.writeCValue(writer, ptr);
try writer.writeAll(", ");
try f.writeCValue(writer, operand);
try writer.writeAll(", ");
try writeMemoryOrder(writer, extra.ordering());
try writer.writeAll(");\n");
return local;
}
fn airAtomicLoad(f: *Function, inst: Air.Inst.Index) !CValue {
const atomic_load = f.air.instructions.items(.data)[inst].atomic_load;
const ptr = try f.resolveInst(atomic_load.ptr);
const ptr_ty = f.air.typeOf(atomic_load.ptr);
if (!ptr_ty.isVolatilePtr() and f.liveness.isUnused(inst))
return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const writer = f.object.writer();
try writer.writeAll(" = zig_atomic_load(");
try f.writeCValue(writer, ptr);
try writer.writeAll(", ");
try writeMemoryOrder(writer, atomic_load.order);
try writer.writeAll(");\n");
return local;
}
fn airAtomicStore(f: *Function, inst: Air.Inst.Index, order: [*:0]const u8) !CValue {
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const ptr = try f.resolveInst(bin_op.lhs);
const element = try f.resolveInst(bin_op.rhs);
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const writer = f.object.writer();
try writer.writeAll(" = zig_atomic_store(");
try f.writeCValue(writer, ptr);
try writer.writeAll(", ");
try f.writeCValue(writer, element);
try writer.print(", {s});\n", .{order});
return local;
}
fn airMemset(f: *Function, inst: Air.Inst.Index) !CValue {
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const extra = f.air.extraData(Air.Bin, pl_op.payload).data;
const dest_ptr = try f.resolveInst(pl_op.operand);
const value = try f.resolveInst(extra.lhs);
const len = try f.resolveInst(extra.rhs);
const writer = f.object.writer();
try writer.writeAll("memset(");
try f.writeCValue(writer, dest_ptr);
try writer.writeAll(", ");
try f.writeCValue(writer, value);
try writer.writeAll(", ");
try f.writeCValue(writer, len);
try writer.writeAll(");\n");
return CValue.none;
}
fn airMemcpy(f: *Function, inst: Air.Inst.Index) !CValue {
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const extra = f.air.extraData(Air.Bin, pl_op.payload).data;
const dest_ptr = try f.resolveInst(pl_op.operand);
const src_ptr = try f.resolveInst(extra.lhs);
const len = try f.resolveInst(extra.rhs);
const writer = f.object.writer();
try writer.writeAll("memcpy(");
try f.writeCValue(writer, dest_ptr);
try writer.writeAll(", ");
try f.writeCValue(writer, src_ptr);
try writer.writeAll(", ");
try f.writeCValue(writer, len);
try writer.writeAll(");\n");
return CValue.none;
}
fn airSetUnionTag(f: *Function, inst: Air.Inst.Index) !CValue {
const bin_op = f.air.instructions.items(.data)[inst].bin_op;
const union_ptr = try f.resolveInst(bin_op.lhs);
const new_tag = try f.resolveInst(bin_op.rhs);
const writer = f.object.writer();
const union_ty = f.air.typeOf(bin_op.lhs).childType();
const target = f.object.dg.module.getTarget();
const layout = union_ty.unionGetLayout(target);
if (layout.tag_size == 0) return CValue.none;
try f.writeCValue(writer, union_ptr);
try writer.writeAll("->tag = ");
try f.writeCValue(writer, new_tag);
try writer.writeAll(";\n");
return CValue.none;
}
fn airGetUnionTag(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst))
return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const un_ty = f.air.typeOf(ty_op.operand);
const writer = f.object.writer();
const operand = try f.resolveInst(ty_op.operand);
const target = f.object.dg.module.getTarget();
const layout = un_ty.unionGetLayout(target);
if (layout.tag_size == 0) return CValue.none;
try writer.writeAll(" = ");
try f.writeCValue(writer, operand);
try writer.writeAll(".tag;\n");
return local;
}
fn airTagName(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const un_op = f.air.instructions.items(.data)[inst].un_op;
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const operand = try f.resolveInst(un_op);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
_ = operand;
_ = local;
return f.fail("TODO: C backend: implement airTagName", .{});
//try writer.writeAll(";\n");
//return local;
}
fn airErrorName(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const un_op = f.air.instructions.items(.data)[inst].un_op;
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const operand = try f.resolveInst(un_op);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
_ = operand;
_ = local;
return f.fail("TODO: C backend: implement airErrorName", .{});
}
fn airSplat(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const operand = try f.resolveInst(ty_op.operand);
const writer = f.object.writer();
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
_ = operand;
_ = local;
return f.fail("TODO: C backend: implement airSplat", .{});
}
fn airSelect(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const writer = f.object.writer();
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
_ = local;
_ = ty_pl;
return f.fail("TODO: C backend: implement airSelect", .{});
}
fn airShuffle(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const ty_op = f.air.instructions.items(.data)[inst].ty_op;
const operand = try f.resolveInst(ty_op.operand);
const writer = f.object.writer();
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
_ = operand;
_ = local;
return f.fail("TODO: C backend: implement airShuffle", .{});
}
fn airReduce(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const reduce = f.air.instructions.items(.data)[inst].reduce;
const operand = try f.resolveInst(reduce.operand);
const writer = f.object.writer();
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
_ = operand;
_ = local;
return f.fail("TODO: C backend: implement airReduce", .{});
}
fn airAggregateInit(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const vector_ty = f.air.getRefType(ty_pl.ty);
const len = vector_ty.vectorLen();
const elements = @ptrCast([]const Air.Inst.Ref, f.air.extra[ty_pl.payload..][0..len]);
const writer = f.object.writer();
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = {");
switch (vector_ty.zigTypeTag()) {
.Struct => {
const tuple = vector_ty.tupleFields();
var i: usize = 0;
for (elements) |elem, elem_index| {
if (tuple.values[elem_index].tag() != .unreachable_value) continue;
const value = try f.resolveInst(elem);
if (i != 0) try writer.writeAll(", ");
try f.writeCValue(writer, value);
i += 1;
}
},
else => |tag| return f.fail("TODO: C backend: implement airAggregateInit for type {s}", .{@tagName(tag)}),
}
try writer.writeAll("};\n");
return local;
}
fn airUnionInit(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const inst_ty = f.air.typeOfIndex(inst);
const ty_pl = f.air.instructions.items(.data)[inst].ty_pl;
const writer = f.object.writer();
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
_ = local;
_ = ty_pl;
return f.fail("TODO: C backend: implement airUnionInit", .{});
}
fn airPrefetch(f: *Function, inst: Air.Inst.Index) !CValue {
const prefetch = f.air.instructions.items(.data)[inst].prefetch;
switch (prefetch.cache) {
.data => {},
// The available prefetch intrinsics do not accept a cache argument; only
// address, rw, and locality. So unless the cache is data, we do not lower
// this instruction.
.instruction => return CValue.none,
}
const ptr = try f.resolveInst(prefetch.ptr);
const writer = f.object.writer();
try writer.writeAll("zig_prefetch(");
try f.writeCValue(writer, ptr);
try writer.print(", {d}, {d});\n", .{
@enumToInt(prefetch.rw), prefetch.locality,
});
return CValue.none;
}
fn airWasmMemorySize(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
try writer.print("zig_wasm_memory_size({d});\n", .{pl_op.payload});
return local;
}
fn airWasmMemoryGrow(f: *Function, inst: Air.Inst.Index) !CValue {
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const operand = try f.resolveInst(pl_op.operand);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
try writer.print("zig_wasm_memory_grow({d}, ", .{pl_op.payload});
try f.writeCValue(writer, operand);
try writer.writeAll(");\n");
return local;
}
fn airNeg(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const un_op = f.air.instructions.items(.data)[inst].un_op;
const writer = f.object.writer();
const inst_ty = f.air.typeOfIndex(inst);
const operand = try f.resolveInst(un_op);
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll("-");
try f.writeCValue(writer, operand);
try writer.writeAll(";\n");
return local;
}
fn airMulAdd(f: *Function, inst: Air.Inst.Index) !CValue {
if (f.liveness.isUnused(inst)) return CValue.none;
const pl_op = f.air.instructions.items(.data)[inst].pl_op;
const extra = f.air.extraData(Air.Bin, pl_op.payload).data;
const inst_ty = f.air.typeOfIndex(inst);
const mulend1 = try f.resolveInst(extra.lhs);
const mulend2 = try f.resolveInst(extra.rhs);
const addend = try f.resolveInst(pl_op.operand);
const writer = f.object.writer();
const target = f.object.dg.module.getTarget();
const fn_name = switch (inst_ty.floatBits(target)) {
16, 32 => "fmaf",
64 => "fma",
80 => if (CType.longdouble.sizeInBits(target) == 80) "fmal" else "__fmax",
128 => if (CType.longdouble.sizeInBits(target) == 128) "fmal" else "fmaq",
else => unreachable,
};
const local = try f.allocLocal(inst_ty, .Const);
try writer.writeAll(" = ");
try writer.print("{s}(", .{fn_name});
try f.writeCValue(writer, mulend1);
try writer.writeAll(", ");
try f.writeCValue(writer, mulend2);
try writer.writeAll(", ");
try f.writeCValue(writer, addend);
try writer.writeAll(");\n");
return local;
}
fn toMemoryOrder(order: std.builtin.AtomicOrder) [:0]const u8 {
return switch (order) {
.Unordered => "memory_order_relaxed",
.Monotonic => "memory_order_consume",
.Acquire => "memory_order_acquire",
.Release => "memory_order_release",
.AcqRel => "memory_order_acq_rel",
.SeqCst => "memory_order_seq_cst",
};
}
fn writeMemoryOrder(w: anytype, order: std.builtin.AtomicOrder) !void {
return w.writeAll(toMemoryOrder(order));
}
fn toAtomicRmwSuffix(order: std.builtin.AtomicRmwOp) []const u8 {
return switch (order) {
.Xchg => "xchg",
.Add => "add",
.Sub => "sub",
.And => "and",
.Nand => "nand",
.Or => "or",
.Xor => "xor",
.Max => "max",
.Min => "min",
};
}
fn IndentWriter(comptime UnderlyingWriter: type) type {
return struct {
const Self = @This();
pub const Error = UnderlyingWriter.Error;
pub const Writer = std.io.Writer(*Self, Error, write);
pub const indent_delta = 1;
underlying_writer: UnderlyingWriter,
indent_count: usize = 0,
current_line_empty: bool = true,
pub fn writer(self: *Self) Writer {
return .{ .context = self };
}
pub fn write(self: *Self, bytes: []const u8) Error!usize {
if (bytes.len == 0) return @as(usize, 0);
const current_indent = self.indent_count * Self.indent_delta;
if (self.current_line_empty and current_indent > 0) {
try self.underlying_writer.writeByteNTimes(' ', current_indent);
}
self.current_line_empty = false;
return self.writeNoIndent(bytes);
}
pub fn insertNewline(self: *Self) Error!void {
_ = try self.writeNoIndent("\n");
}
pub fn pushIndent(self: *Self) void {
self.indent_count += 1;
}
pub fn popIndent(self: *Self) void {
assert(self.indent_count != 0);
self.indent_count -= 1;
}
fn writeNoIndent(self: *Self, bytes: []const u8) Error!usize {
if (bytes.len == 0) return @as(usize, 0);
try self.underlying_writer.writeAll(bytes);
if (bytes[bytes.len - 1] == '\n') {
self.current_line_empty = true;
}
return bytes.len;
}
};
}
fn toCIntBits(zig_bits: u32) ?u32 {
for (&[_]u8{ 8, 16, 32, 64, 128 }) |c_bits| {
if (zig_bits <= c_bits) {
return c_bits;
}
}
return null;
}
fn signAbbrev(signedness: std.builtin.Signedness) u8 {
return switch (signedness) {
.signed => 'i',
.unsigned => 'u',
};
}
fn intMax(ty: Type, target: std.Target, buf: []u8) []const u8 {
switch (ty.tag()) {
.c_short => return "SHRT_MAX",
.c_ushort => return "USHRT_MAX",
.c_int => return "INT_MAX",
.c_uint => return "UINT_MAX",
.c_long => return "LONG_MAX",
.c_ulong => return "ULONG_MAX",
.c_longlong => return "LLONG_MAX",
.c_ulonglong => return "ULLONG_MAX",
else => {
const int_info = ty.intInfo(target);
const rhs = @intCast(u7, int_info.bits - @boolToInt(int_info.signedness == .signed));
const val = (@as(u128, 1) << rhs) - 1;
// TODO make this integer literal have a suffix if necessary (such as "ull")
return std.fmt.bufPrint(buf, "{}", .{val}) catch |err| switch (err) {
error.NoSpaceLeft => unreachable,
};
},
}
}
fn intMin(ty: Type, target: std.Target, buf: []u8) []const u8 {
switch (ty.tag()) {
.c_short => return "SHRT_MIN",
.c_int => return "INT_MIN",
.c_long => return "LONG_MIN",
.c_longlong => return "LLONG_MIN",
else => {
const int_info = ty.intInfo(target);
assert(int_info.signedness == .signed);
const val = v: {
if (int_info.bits == 0) break :v 0;
const rhs = @intCast(u7, (int_info.bits - 1));
break :v -(@as(i128, 1) << rhs);
};
return std.fmt.bufPrint(buf, "{d}", .{val}) catch |err| switch (err) {
error.NoSpaceLeft => unreachable,
};
},
}
}
fn loweredFnRetTyHasBits(fn_ty: Type) bool {
const ret_ty = fn_ty.fnReturnType();
if (ret_ty.hasRuntimeBitsIgnoreComptime()) {
return true;
}
if (ret_ty.isError()) {
return true;
}
return false;
}
fn isByRef(ty: Type) bool {
_ = ty;
return false;
}