mirror/zig
1
0
Fork 0
mirror of https://github.com/ziglang/zig.git synced 2025-12-27 16:43:07 +00:00
Code Issues Packages Projects Releases Wiki Activity

cbe: correctly implement volatile memset

Browse Source
This commit is contained in:
Jacob Young 2022-11-01 20:43:54 -04:00
parent 771dadc5e0
commit d8635af1dc
1 changed files with 30 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
src/codegen/c.zig
View File

@ -4930,19 +4930,39 @@ fn airMemset(f: *Function, inst: Air.Inst.Index) !CValue {
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();
if (dest_ty.isVolatilePtr()) {
var u8_ptr_pl = dest_ty.ptrInfo();
u8_ptr_pl.data.pointee_type = Type.u8;
const u8_ptr_ty = Type.initPayload(&u8_ptr_pl.base);
try writer.writeAll("for (");
const index = try f.allocLocal(Type.usize, .Mut);
try writer.writeAll(" = ");
try f.object.dg.renderValue(writer, Type.usize, Value.zero, .Initializer);
try writer.writeAll("; ");
try f.writeCValue(writer, index, .Other);
try writer.writeAll(" != ");
try f.writeCValue(writer, len, .Other);
try writer.writeAll("; ");
try f.writeCValue(writer, index, .Other);
try writer.writeAll(" += ");
try f.object.dg.renderValue(writer, Type.usize, Value.one, .Other);
try writer.writeAll(") ((");
try f.renderTypecast(writer, u8_ptr_ty);
try writer.writeByte(')');
try f.writeCValue(writer, dest_ptr, .FunctionArgument);
try writer.writeAll(")[");
try f.writeCValue(writer, index, .Other);
try writer.writeAll("] = ");
try f.writeCValue(writer, value, .FunctionArgument);
try writer.writeAll(";\n");
return CValue.none;
}
try writer.writeAll("memset(");
if (dest_ty.isVolatilePtr()) {
// This is wrong, but good enough for now.
var remove_volatile_pl = dest_ty.ptrInfo();
remove_volatile_pl.data.@"volatile" = false;
const remove_volatile_ty = Type.initPayload(&remove_volatile_pl.base);
try writer.writeByte('(');
try f.renderTypecast(writer, remove_volatile_ty);
try writer.writeByte(')');
}
try f.writeCValue(writer, dest_ptr, .FunctionArgument);
try writer.writeAll(", ");
try f.writeCValue(writer, value, .FunctionArgument);