mirror/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2026-02-12 20:37:54 +00:00
Code Issues Packages Projects Releases Wiki Activity

LLVM: pass slices as ptr/len combo

Browse Source 
LLVM optimization passes handle this better, and it allows Zig to
specify pointer parameter attributes such as readonly, nonnull, noalias,
and alignment.

closes #561
This commit is contained in:
Andrew Kelley 2022-05-31 18:25:57 -07:00
parent 356a865b87
commit 2f9533f639
1 changed files with 63 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

70
src/codegen/llvm.zig
View File

@ -712,6 +712,7 @@ pub const Object = struct {
.byval => {
const param_ty = fn_info.param_types[it.zig_index - 1];
const param = llvm_func.getParam(llvm_arg_i);
try args.ensureUnusedCapacity(1);
if (isByRef(param_ty)) {
const alignment = param_ty.abiAlignment(target);
@ -720,9 +721,9 @@ pub const Object = struct {
arg_ptr.setAlignment(alignment);
const store_inst = builder.buildStore(param, arg_ptr);
store_inst.setAlignment(alignment);
try args.append(arg_ptr);
args.appendAssumeCapacity(arg_ptr);
} else {
try args.append(param);
args.appendAssumeCapacity(param);
if (param_ty.isPtrAtRuntime()) {
const ptr_info = param_ty.ptrInfo().data;
@ -756,13 +757,15 @@ pub const Object = struct {
llvm_arg_i += 1;
try args.ensureUnusedCapacity(1);
if (isByRef(param_ty)) {
try args.append(param);
args.appendAssumeCapacity(param);
} else {
const alignment = param_ty.abiAlignment(target);
const load_inst = builder.buildLoad(param, "");
load_inst.setAlignment(alignment);
try args.append(load_inst);
args.appendAssumeCapacity(load_inst);
}
},
.abi_sized_int => {
@ -784,14 +787,44 @@ pub const Object = struct {
const store_inst = builder.buildStore(param, casted_ptr);
store_inst.setAlignment(alignment);
try args.ensureUnusedCapacity(1);
if (isByRef(param_ty)) {
try args.append(arg_ptr);
args.appendAssumeCapacity(arg_ptr);
} else {
const load_inst = builder.buildLoad(arg_ptr, "");
load_inst.setAlignment(alignment);
try args.append(load_inst);
args.appendAssumeCapacity(load_inst);
}
},
.slice => {
const param_ty = fn_info.param_types[it.zig_index - 1];
const ptr_info = param_ty.ptrInfo().data;
if (math.cast(u5, it.zig_index - 1)) |i| {
if (@truncate(u1, fn_info.noalias_bits >> i) != 0) {
dg.addArgAttr(llvm_func, llvm_arg_i, "noalias");
}
}
dg.addArgAttr(llvm_func, llvm_arg_i, "nonnull");
if (!ptr_info.mutable) {
dg.addArgAttr(llvm_func, llvm_arg_i, "readonly");
}
if (ptr_info.@"align" != 0) {
dg.addArgAttrInt(llvm_func, llvm_arg_i, "align", ptr_info.@"align");
} else {
dg.addArgAttrInt(llvm_func, llvm_arg_i, "align", ptr_info.pointee_type.abiAlignment(target));
}
const ptr_param = llvm_func.getParam(llvm_arg_i);
llvm_arg_i += 1;
const len_param = llvm_func.getParam(llvm_arg_i);
llvm_arg_i += 1;
const slice_llvm_ty = try dg.lowerType(param_ty);
const partial = builder.buildInsertValue(slice_llvm_ty.getUndef(), ptr_param, 0, "");
const aggregate = builder.buildInsertValue(partial, len_param, 1, "");
try args.append(aggregate);
},
.multiple_llvm_ints => {
const param_ty = fn_info.param_types[it.zig_index - 1];
const llvm_ints = it.llvm_types_buffer[0..it.llvm_types_len];
@ -2743,6 +2776,17 @@ pub const DeclGen = struct {
const abi_size = @intCast(c_uint, param_ty.abiSize(target));
try llvm_params.append(dg.context.intType(abi_size * 8));
},
.slice => {
const param_ty = fn_info.param_types[it.zig_index - 1];
var buf: Type.SlicePtrFieldTypeBuffer = undefined;
const ptr_ty = param_ty.slicePtrFieldType(&buf);
const ptr_llvm_ty = try dg.lowerType(ptr_ty);
const len_llvm_ty = try dg.lowerType(Type.usize);
try llvm_params.ensureUnusedCapacity(2);
llvm_params.appendAssumeCapacity(ptr_llvm_ty);
llvm_params.appendAssumeCapacity(len_llvm_ty);
},
.multiple_llvm_ints => {
const param_ty = fn_info.param_types[it.zig_index - 1];
const llvm_ints = it.llvm_types_buffer[0..it.llvm_types_len];
@ -4205,6 +4249,15 @@ pub const FuncGen = struct {
try llvm_args.append(load_inst);
}
},
.slice => {
const arg = args[it.zig_index - 1];
const llvm_arg = try self.resolveInst(arg);
const ptr = self.builder.buildExtractValue(llvm_arg, 0, "");
const len = self.builder.buildExtractValue(llvm_arg, 1, "");
try llvm_args.ensureUnusedCapacity(2);
llvm_args.appendAssumeCapacity(ptr);
llvm_args.appendAssumeCapacity(len);
},
.multiple_llvm_ints => {
const arg = args[it.zig_index - 1];
const param_ty = self.air.typeOf(arg);
@ -8811,6 +8864,7 @@ const ParamTypeIterator = struct {
byref,
abi_sized_int,
multiple_llvm_ints,
slice,
};
fn next(it: *ParamTypeIterator) ?Lowering {
@ -8826,7 +8880,9 @@ const ParamTypeIterator = struct {
.Unspecified, .Inline => {
it.zig_index += 1;
it.llvm_index += 1;
if (isByRef(ty)) {
if (ty.isSlice()) {
return .slice;
} else if (isByRef(ty)) {
return .byref;
} else {
return .byval;