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wasm: shl_with_overflow ensure rhs is coerced

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Both operands must have the same Wasm type before we are allowed
to perform any binary operation on the values.
This commit is contained in:
Luuk de Gram
2023-05-29 14:23:51 +02:00
parent e36cc0ce8f
commit 7e10cf4fbe
1 changed files with 12 additions and 3 deletions
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15
src/arch/wasm/CodeGen.zig
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@@ -5707,6 +5707,7 @@ fn airShlWithOverflow(func: *CodeGen, inst: Air.Inst.Index) InnerError!void {
const lhs = try func.resolveInst(extra.lhs);
const rhs = try func.resolveInst(extra.rhs);
const lhs_ty = func.air.typeOf(extra.lhs);
const rhs_ty = func.air.typeOf(extra.rhs);
if (lhs_ty.zigTypeTag() == .Vector) {
return func.fail("TODO: Implement overflow arithmetic for vectors", .{});
@@ -5718,7 +5719,15 @@ fn airShlWithOverflow(func: *CodeGen, inst: Air.Inst.Index) InnerError!void {
return func.fail("TODO: Implement shl_with_overflow for integer bitsize: {d}", .{int_info.bits});
};
var shl = try (try func.binOp(lhs, rhs, lhs_ty, .shl)).toLocal(func, lhs_ty);
// Ensure rhs is coerced to lhs as they must have the same WebAssembly types
// before we can perform any binary operation.
const rhs_wasm_bits = toWasmBits(rhs_ty.intInfo(func.target).bits).?;
const rhs_final = if (wasm_bits != rhs_wasm_bits) blk: {
const rhs_casted = try func.intcast(rhs, rhs_ty, lhs_ty);
break :blk try rhs_casted.toLocal(func, lhs_ty);
} else rhs;
var shl = try (try func.binOp(lhs, rhs_final, lhs_ty, .shl)).toLocal(func, lhs_ty);
defer shl.free(func);
var result = if (wasm_bits != int_info.bits) blk: {
break :blk try (try func.wrapOperand(shl, lhs_ty)).toLocal(func, lhs_ty);
@@ -5729,11 +5738,11 @@ fn airShlWithOverflow(func: *CodeGen, inst: Air.Inst.Index) InnerError!void {
// emit lhs to stack to we can keep 'wrapped' on the stack also
try func.emitWValue(lhs);
const abs = try func.signAbsValue(shl, lhs_ty);
const wrapped = try func.wrapBinOp(abs, rhs, lhs_ty, .shr);
const wrapped = try func.wrapBinOp(abs, rhs_final, lhs_ty, .shr);
break :blk try func.cmp(.{ .stack = {} }, wrapped, lhs_ty, .neq);
} else blk: {
try func.emitWValue(lhs);
const shr = try func.binOp(result, rhs, lhs_ty, .shr);
const shr = try func.binOp(result, rhs_final, lhs_ty, .shr);
break :blk try func.cmp(.{ .stack = {} }, shr, lhs_ty, .neq);
};
var overflow_local = try overflow_bit.toLocal(func, Type.initTag(.u1));