mirror/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2026-01-01 19:13:16 +00:00
Code Issues Packages Projects Releases Wiki Activity

C backend: implement try instruction

Browse Source
This commit is contained in:
Andrew Kelley 2022-06-03 16:10:41 -07:00 committed by Jakub Konka
parent 779770cff5
commit d2f31d315e
1 changed files with 92 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

94
src/codegen/c.zig
View File

@ -1875,8 +1875,8 @@ fn genBody(f: *Function, body: []const Air.Inst.Index) error{ AnalysisFail, OutO
.union_init => try airUnionInit(f, inst),
.prefetch => try airPrefetch(f, inst),
.@"try" => @panic("TODO"),
.try_ptr => @panic("TODO"),
.@"try" => try airTry(f, inst),
.try_ptr => try airTryPtr(f, inst),
.dbg_var_ptr,
.dbg_var_val,
@ -2864,6 +2864,91 @@ fn airBlock(f: *Function, inst: Air.Inst.Index) !CValue {
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 {
if (err_union_ty.errorUnionSet().errorSetCardinality() == .zero) {
// If the error set has no fields, then the payload and the error
// union are the same value.
return err_union;
}
const payload_ty = err_union_ty.errorUnionPayload();
const payload_has_bits = payload_ty.hasRuntimeBitsIgnoreComptime();
const writer = f.object.writer();
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).?;
@ -4224,3 +4309,8 @@ fn loweredFnRetTyHasBits(fn_ty: Type) bool {
}
return false;
}
fn isByRef(ty: Type) bool {
_ = ty;
return false;
}