motiejus/zig
1
Fork 0
Code Releases Activity

wasm: airStructFieldPtr - Support packed structs

Browse Source 
Simplifies the airStructFieldPtr(index) functions to only obtain the
correct struct type and field index, which is then passed into the
structFieldPtr function. This function now calculates the byte-offset
of the field's address and returns a new `WValue` with this offset.
This means we only have to do this calculation in a single function,
and no longer have to duplicate any logic. This also handles both
regular (tagged) unions and packed unions.
This commit is contained in:
Luuk de Gram
2022-11-25 19:14:24 +01:00
parent eb2caf9390
commit 4af5bbde53
1 changed files with 13 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

30
src/arch/wasm/CodeGen.zig
View File

@@ -3131,13 +3131,7 @@ fn airStructFieldPtr(func: *CodeGen, inst: Air.Inst.Index) InnerError!void {
const struct_ptr = try func.resolveInst(extra.data.struct_operand);
const struct_ty = func.air.typeOf(extra.data.struct_operand).childType();
const offset = std.math.cast(u32, struct_ty.structFieldOffset(extra.data.field_index, func.target)) orelse {
const module = func.bin_file.base.options.module.?;
return func.fail("Field type '{}' too big to fit into stack frame", .{
struct_ty.structFieldType(extra.data.field_index).fmt(module),
});
};
const result = try func.structFieldPtr(struct_ptr, offset);
const result = try func.structFieldPtr(struct_ptr, struct_ty, extra.data.field_index);
func.finishAir(inst, result, &.{extra.data.struct_operand});
}
@@ -3146,21 +3140,23 @@ fn airStructFieldPtrIndex(func: *CodeGen, inst: Air.Inst.Index, index: u32) Inne
if (func.liveness.isUnused(inst)) return func.finishAir(inst, .none, &.{ty_op.operand});
const struct_ptr = try func.resolveInst(ty_op.operand);
const struct_ty = func.air.typeOf(ty_op.operand).childType();
const field_ty = struct_ty.structFieldType(index);
const offset = std.math.cast(u32, struct_ty.structFieldOffset(index, func.target)) orelse {
const module = func.bin_file.base.options.module.?;
return func.fail("Field type '{}' too big to fit into stack frame", .{
field_ty.fmt(module),
});
};
const result = try func.structFieldPtr(struct_ptr, offset);
const result = try func.structFieldPtr(struct_ptr, struct_ty, index);
func.finishAir(inst, result, &.{ty_op.operand});
}
fn structFieldPtr(func: *CodeGen, struct_ptr: WValue, offset: u32) InnerError!WValue {
fn structFieldPtr(func: *CodeGen, struct_ptr: WValue, struct_ty: Type, index: u32) InnerError!WValue {
const offset = switch (struct_ty.containerLayout()) {
.Packed => switch (struct_ty.zigTypeTag()) {
.Struct => struct_ty.packedStructFieldByteOffset(index, func.target),
.Union => 0,
else => unreachable,
},
else => struct_ty.structFieldOffset(index, func.target),
};
switch (struct_ptr) {
.stack_offset => |stack_offset| {
return WValue{ .stack_offset = .{ .value = stack_offset.value + offset, .references = 1 } };
return WValue{ .stack_offset = .{ .value = stack_offset.value + @intCast(u32, offset), .references = 1 } };
},
else => return func.buildPointerOffset(struct_ptr, offset, .new),
}