srctree

Jacob Young parent eaa6218f 941d3a2b
x86_64: fix miscompilations on baseline

inlinesplit
src/arch/x86_64/CodeGen.zig added: 35, removed: 38, total 0
@@ -5653,10 +5653,10 @@ fn airCtz(self: *Self, inst: Air.Inst.Index) !void {
const dst_lock = self.register_manager.lockReg(dst_reg);
defer if (dst_lock) |lock| self.register_manager.unlockReg(lock);
 
const wide_ty = if (src_bits <= 8) Type.u16 else src_ty;
if (self.hasFeature(.bmi)) {
if (src_bits <= 64) {
const extra_bits = self.regExtraBits(src_ty) + @as(u64, if (src_bits <= 8) 8 else 0);
const wide_ty = if (src_bits <= 8) Type.u16 else src_ty;
const masked_mcv = if (extra_bits > 0) masked: {
const tmp_mcv = tmp: {
if (src_mcv.isImmediate() or self.liveness.operandDies(inst, 0))
@@ -5718,7 +5718,7 @@ fn airCtz(self: *Self, inst: Air.Inst.Index) !void {
defer self.register_manager.unlockReg(wide_lock);
 
try self.truncateRegister(src_ty, wide_reg);
try self.genBinOpMir(.{ ._, .bsf }, Type.u16, dst_mcv, .{ .register = wide_reg });
try self.genBinOpMir(.{ ._, .bsf }, wide_ty, dst_mcv, .{ .register = wide_reg });
} else try self.genBinOpMir(.{ ._, .bsf }, src_ty, dst_mcv, mat_src_mcv);
 
const cmov_abi_size = @max(@as(u32, @intCast(dst_ty.abiSize(mod))), 2);
@@ -5890,6 +5890,7 @@ fn genByteSwap(
) !MCValue {
const mod = self.bin_file.comp.module.?;
const ty_op = self.air.instructions.items(.data)[@intFromEnum(inst)].ty_op;
const have_movbe = self.hasFeature(.movbe);
 
if (src_ty.zigTypeTag(mod) == .Vector) return self.fail(
"TODO implement genByteSwap for {}",
@@ -5935,46 +5936,42 @@ fn genByteSwap(
const dst_locks = self.register_manager.lockRegsAssumeUnused(2, dst_regs);
defer for (dst_locks) |lock| self.register_manager.unlockReg(lock);
 
if (src_mcv.isMemory()) {
try self.asmRegisterMemory(
.{ ._, .movbe },
dst_regs[0],
try src_mcv.address().offset(8).deref().mem(self, .qword),
);
try self.asmRegisterMemory(.{ ._, .movbe }, dst_regs[1], try src_mcv.mem(self, .qword));
} else for (dst_regs, src_mcv.register_pair) |dst_reg, src_reg| {
try self.asmRegisterRegister(.{ ._, .mov }, dst_reg.to64(), src_reg.to64());
try self.asmRegister(.{ ._, .bswap }, dst_reg.to64());
for (dst_regs, 0..) |dst_reg, limb_index| {
if (src_mcv.isMemory()) {
try self.asmRegisterMemory(
.{ ._, if (have_movbe) .movbe else .mov },
dst_reg.to64(),
try src_mcv.address().offset(@intCast(limb_index * 8)).deref().mem(self, .qword),
);
if (!have_movbe) try self.asmRegister(.{ ._, .bswap }, dst_reg.to64());
} else {
try self.asmRegisterRegister(
.{ ._, .mov },
dst_reg.to64(),
src_mcv.register_pair[limb_index].to64(),
);
try self.asmRegister(.{ ._, .bswap }, dst_reg.to64());
}
}
return .{ .register_pair = dst_regs };
return .{ .register_pair = .{ dst_regs[1], dst_regs[0] } };
},
}
 
if (src_mcv.isRegister()) {
const dst_mcv: MCValue = if (mem_ok)
try self.allocRegOrMem(inst, true)
else
.{ .register = try self.register_manager.allocReg(inst, abi.RegisterClass.gp) };
if (dst_mcv.isRegister()) {
const dst_lock = self.register_manager.lockRegAssumeUnused(dst_mcv.register);
defer self.register_manager.unlockReg(dst_lock);
const dst_mcv: MCValue = if (mem_ok and have_movbe and src_mcv.isRegister())
try self.allocRegOrMem(inst, true)
else
.{ .register = try self.register_manager.allocReg(inst, abi.RegisterClass.gp) };
if (dst_mcv.getReg()) |dst_reg| {
const dst_lock = self.register_manager.lockRegAssumeUnused(dst_mcv.register);
defer self.register_manager.unlockReg(dst_lock);
 
try self.genSetReg(dst_mcv.register, src_ty, src_mcv);
switch (abi_size) {
else => unreachable,
2 => try self.genBinOpMir(.{ ._l, .ro }, src_ty, dst_mcv, .{ .immediate = 8 }),
3...8 => try self.genUnOpMir(.{ ._, .bswap }, src_ty, dst_mcv),
}
} else try self.genBinOpMir(.{ ._, .movbe }, src_ty, dst_mcv, src_mcv);
return dst_mcv;
}
 
const dst_reg = try self.register_manager.allocReg(inst, abi.RegisterClass.gp);
const dst_mcv = MCValue{ .register = dst_reg };
const dst_lock = self.register_manager.lockRegAssumeUnused(dst_reg);
defer self.register_manager.unlockReg(dst_lock);
 
try self.genBinOpMir(.{ ._, .movbe }, src_ty, dst_mcv, src_mcv);
try self.genSetReg(dst_reg, src_ty, src_mcv);
switch (abi_size) {
else => unreachable,
2 => try self.genBinOpMir(.{ ._l, .ro }, src_ty, dst_mcv, .{ .immediate = 8 }),
3...8 => try self.genUnOpMir(.{ ._, .bswap }, src_ty, dst_mcv),
}
} else try self.genBinOpMir(.{ ._, .movbe }, src_ty, dst_mcv, src_mcv);
return dst_mcv;
}