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stage2: use lowerToRmEnc to lower two-operand imul

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Fix mismatched register sizes in codegen.
This commit is contained in:
Jakub Konka 2021-12-23 20:51:48 +01:00
parent c50bb2b80f
commit dba5df64ea
2 changed files with 5 additions and 12 deletions
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4
src/arch/x86_64/CodeGen.zig
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@ -1717,7 +1717,7 @@ fn genIMulOpMir(self: *Self, dst_ty: Type, dst_mcv: MCValue, src_mcv: MCValue) !
_ = try self.addInst(.{
.tag = .imul_complex,
.ops = (Mir.Ops{
.reg1 = dst_reg,
.reg1 = registerAlias(dst_reg, @divExact(src_reg.size(), 8)),
.reg2 = src_reg,
}).encode(),
.data = undefined,
@ -1766,7 +1766,7 @@ fn genIMulOpMir(self: *Self, dst_ty: Type, dst_mcv: MCValue, src_mcv: MCValue) !
_ = try self.addInst(.{
.tag = .imul_complex,
.ops = (Mir.Ops{
.reg1 = dst_reg,
.reg1 = registerAlias(dst_reg, @divExact(src_reg.size(), 8)),
.reg2 = src_reg,
}).encode(),
.data = undefined,

13
src/arch/x86_64/Emit.zig
View File

@ -380,6 +380,7 @@ const Tag = enum {
@"test",
brk,
nop,
imul,
syscall,
ret_near,
ret_far,
@ -635,6 +636,7 @@ inline fn getOpCode(tag: Tag, enc: Encoding, is_one_byte: bool) ?OpCode {
.cmp => OpCode.oneByte(if (is_one_byte) 0x3a else 0x3b),
.mov => OpCode.oneByte(if (is_one_byte) 0x8a else 0x8b),
.lea => OpCode.oneByte(if (is_one_byte) 0x8c else 0x8d),
.imul => OpCode.twoByte(0x0f, 0xaf),
else => null,
},
.oi => return switch (tag) {
@ -1378,16 +1380,7 @@ fn mirIMulComplex(emit: *Emit, inst: Mir.Inst.Index) InnerError!void {
assert(tag == .imul_complex);
const ops = Mir.Ops.decode(emit.mir.instructions.items(.ops)[inst]);
switch (ops.flags) {
0b00 => {
const encoder = try Encoder.init(emit.code, 4);
encoder.rex(.{
.w = ops.reg1.size() == 64,
.r = ops.reg1.isExtended(),
.b = ops.reg2.isExtended(),
});
encoder.opcode_2byte(0x0f, 0xaf);
encoder.modRm_direct(ops.reg1.lowId(), ops.reg2.lowId());
},
0b00 => return lowerToRmEnc(.imul, ops.reg1, RegisterOrMemory.reg(ops.reg2), emit.code),
0b10 => {
const imm = emit.mir.instructions.items(.data)[inst].imm;
const opc: u8 = if (imm <= math.maxInt(i8)) 0x6b else 0x69;