[X86] Mark FP32_TO_INT16_IN_MEM/FP32_TO_INT32_IN_MEM/FP32_TO_INT64_IN_MEM as clobbering EFLAGS to prevent mis-scheduling during conversion from SelectionDAG to MIR.

After r354178, these instruction expand to a sequence that uses an OR instruction. That OR clobbers EFLAGS so we need to state that to avoid accidentally using the clobbered flags.

Our tests show the bug, but I didn't notice because the SETcc instructions didn't move after r354178 since it used to be safe to do the fp->int conversion first.

We should probably convert this whole sequence to SelectionDAG instead of a custom inserter to avoid mistakes like this.

Fixes PR40779

llvm-svn: 354395

3 files changed, 55 insertions, 53 deletions

diff --git a/llvm/lib/Target/X86/X86InstrFPStack.td b/llvm/lib/Target/X86/X86InstrFPStack.td
index 753e33b5f99..f46aae17515 100644
--- a/llvm/lib/Target/X86/X86InstrFPStack.td
+++ b/llvm/lib/Target/X86/X86InstrFPStack.td
@@ -113,7 +113,9 @@ def fpimmneg1 : FPImmLeaf<fAny, [{
 }]>;
 
 // Some 'special' instructions - expanded after instruction selection.
-let usesCustomInserter = 1, hasNoSchedulingInfo = 1 in {
+// Clobbers EFLAGS due to OR instruction used internally.
+// FIXME: Can we model this in SelectionDAG?
+let usesCustomInserter = 1, hasNoSchedulingInfo = 1, Defs = [EFLAGS] in {
   def FP32_TO_INT16_IN_MEM : PseudoI<(outs), (ins i16mem:$dst, RFP32:$src),
                               [(X86fp_to_i16mem RFP32:$src, addr:$dst)]>;
   def FP32_TO_INT32_IN_MEM : PseudoI<(outs), (ins i32mem:$dst, RFP32:$src),
diff --git a/llvm/test/CodeGen/X86/fp-cvt.ll b/llvm/test/CodeGen/X86/fp-cvt.ll
index be09718eaac..8164651f996 100644
--- a/llvm/test/CodeGen/X86/fp-cvt.ll
+++ b/llvm/test/CodeGen/X86/fp-cvt.ll
@@ -457,15 +457,15 @@ define i64 @fptoui_i64_fp80(x86_fp80 %a0) nounwind {
 ; X86-NEXT:    fldz
 ; X86-NEXT:  .LBB10_2:
 ; X86-NEXT:    fstp %st(0)
+; X86-NEXT:    setbe %al
 ; X86-NEXT:    fnstcw {{[0-9]+}}(%esp)
-; X86-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; X86-NEXT:    xorl %edx, %edx
-; X86-NEXT:    orl $3072, %eax # imm = 0xC00
-; X86-NEXT:    movw %ax, {{[0-9]+}}(%esp)
+; X86-NEXT:    movzwl {{[0-9]+}}(%esp), %ecx
+; X86-NEXT:    orl $3072, %ecx # imm = 0xC00
+; X86-NEXT:    movw %cx, {{[0-9]+}}(%esp)
 ; X86-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; X86-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; X86-NEXT:    fldcw {{[0-9]+}}(%esp)
-; X86-NEXT:    setbe %dl
+; X86-NEXT:    movzbl %al, %edx
 ; X86-NEXT:    shll $31, %edx
 ; X86-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; X86-NEXT:    movl {{[0-9]+}}(%esp), %eax
@@ -479,19 +479,19 @@ define i64 @fptoui_i64_fp80(x86_fp80 %a0) nounwind {
 ; X64-X87-NEXT:    flds {{.*}}(%rip)
 ; X64-X87-NEXT:    fld %st(1)
 ; X64-X87-NEXT:    fsub %st(1), %st
+; X64-X87-NEXT:    xorl %eax, %eax
 ; X64-X87-NEXT:    fxch %st(1)
 ; X64-X87-NEXT:    fucompi %st(2), %st
 ; X64-X87-NEXT:    fcmovnbe %st(1), %st
 ; X64-X87-NEXT:    fstp %st(1)
+; X64-X87-NEXT:    setbe %al
 ; X64-X87-NEXT:    fnstcw -{{[0-9]+}}(%rsp)
 ; X64-X87-NEXT:    movzwl -{{[0-9]+}}(%rsp), %ecx
-; X64-X87-NEXT:    xorl %eax, %eax
 ; X64-X87-NEXT:    orl $3072, %ecx # imm = 0xC00
 ; X64-X87-NEXT:    movw %cx, -{{[0-9]+}}(%rsp)
 ; X64-X87-NEXT:    fldcw -{{[0-9]+}}(%rsp)
 ; X64-X87-NEXT:    fistpll -{{[0-9]+}}(%rsp)
 ; X64-X87-NEXT:    fldcw -{{[0-9]+}}(%rsp)
-; X64-X87-NEXT:    setbe %al
 ; X64-X87-NEXT:    shlq $63, %rax
 ; X64-X87-NEXT:    xorq -{{[0-9]+}}(%rsp), %rax
 ; X64-X87-NEXT:    retq
@@ -539,15 +539,15 @@ define i64 @fptoui_i64_fp80_ld(x86_fp80 *%a0) nounwind {
 ; X86-NEXT:    fldz
 ; X86-NEXT:  .LBB11_2:
 ; X86-NEXT:    fstp %st(0)
+; X86-NEXT:    setbe %al
 ; X86-NEXT:    fnstcw {{[0-9]+}}(%esp)
-; X86-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; X86-NEXT:    xorl %edx, %edx
-; X86-NEXT:    orl $3072, %eax # imm = 0xC00
-; X86-NEXT:    movw %ax, {{[0-9]+}}(%esp)
+; X86-NEXT:    movzwl {{[0-9]+}}(%esp), %ecx
+; X86-NEXT:    orl $3072, %ecx # imm = 0xC00
+; X86-NEXT:    movw %cx, {{[0-9]+}}(%esp)
 ; X86-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; X86-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; X86-NEXT:    fldcw {{[0-9]+}}(%esp)
-; X86-NEXT:    setbe %dl
+; X86-NEXT:    movzbl %al, %edx
 ; X86-NEXT:    shll $31, %edx
 ; X86-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; X86-NEXT:    movl {{[0-9]+}}(%esp), %eax
@@ -561,19 +561,19 @@ define i64 @fptoui_i64_fp80_ld(x86_fp80 *%a0) nounwind {
 ; X64-X87-NEXT:    flds {{.*}}(%rip)
 ; X64-X87-NEXT:    fld %st(1)
 ; X64-X87-NEXT:    fsub %st(1), %st
+; X64-X87-NEXT:    xorl %eax, %eax
 ; X64-X87-NEXT:    fxch %st(1)
 ; X64-X87-NEXT:    fucompi %st(2), %st
 ; X64-X87-NEXT:    fcmovnbe %st(1), %st
 ; X64-X87-NEXT:    fstp %st(1)
+; X64-X87-NEXT:    setbe %al
 ; X64-X87-NEXT:    fnstcw -{{[0-9]+}}(%rsp)
 ; X64-X87-NEXT:    movzwl -{{[0-9]+}}(%rsp), %ecx
-; X64-X87-NEXT:    xorl %eax, %eax
 ; X64-X87-NEXT:    orl $3072, %ecx # imm = 0xC00
 ; X64-X87-NEXT:    movw %cx, -{{[0-9]+}}(%rsp)
 ; X64-X87-NEXT:    fldcw -{{[0-9]+}}(%rsp)
 ; X64-X87-NEXT:    fistpll -{{[0-9]+}}(%rsp)
 ; X64-X87-NEXT:    fldcw -{{[0-9]+}}(%rsp)
-; X64-X87-NEXT:    setbe %al
 ; X64-X87-NEXT:    shlq $63, %rax
 ; X64-X87-NEXT:    xorq -{{[0-9]+}}(%rsp), %rax
 ; X64-X87-NEXT:    retq
diff --git a/llvm/test/CodeGen/X86/scalar-fp-to-i64.ll b/llvm/test/CodeGen/X86/scalar-fp-to-i64.ll
index ec9156b1a94..7576aa3eb9c 100644
--- a/llvm/test/CodeGen/X86/scalar-fp-to-i64.ll
+++ b/llvm/test/CodeGen/X86/scalar-fp-to-i64.ll
@@ -289,15 +289,15 @@ define i64 @f_to_u64(float %a) nounwind {
 ; X87_WIN-NEXT:    fldz
 ; X87_WIN-NEXT:  LBB0_2:
 ; X87_WIN-NEXT:    fstp %st(0)
+; X87_WIN-NEXT:    setbe %al
 ; X87_WIN-NEXT:    fnstcw {{[0-9]+}}(%esp)
-; X87_WIN-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; X87_WIN-NEXT:    xorl %edx, %edx
-; X87_WIN-NEXT:    orl $3072, %eax # imm = 0xC00
-; X87_WIN-NEXT:    movw %ax, {{[0-9]+}}(%esp)
+; X87_WIN-NEXT:    movzwl {{[0-9]+}}(%esp), %ecx
+; X87_WIN-NEXT:    orl $3072, %ecx # imm = 0xC00
+; X87_WIN-NEXT:    movw %cx, {{[0-9]+}}(%esp)
 ; X87_WIN-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; X87_WIN-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; X87_WIN-NEXT:    fldcw {{[0-9]+}}(%esp)
-; X87_WIN-NEXT:    setbe %dl
+; X87_WIN-NEXT:    movzbl %al, %edx
 ; X87_WIN-NEXT:    shll $31, %edx
 ; X87_WIN-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; X87_WIN-NEXT:    movl {{[0-9]+}}(%esp), %eax
@@ -323,15 +323,15 @@ define i64 @f_to_u64(float %a) nounwind {
 ; X87_LIN-NEXT:    fldz
 ; X87_LIN-NEXT:  .LBB0_2:
 ; X87_LIN-NEXT:    fstp %st(0)
+; X87_LIN-NEXT:    setbe %al
 ; X87_LIN-NEXT:    fnstcw {{[0-9]+}}(%esp)
-; X87_LIN-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; X87_LIN-NEXT:    xorl %edx, %edx
-; X87_LIN-NEXT:    orl $3072, %eax # imm = 0xC00
-; X87_LIN-NEXT:    movw %ax, {{[0-9]+}}(%esp)
+; X87_LIN-NEXT:    movzwl {{[0-9]+}}(%esp), %ecx
+; X87_LIN-NEXT:    orl $3072, %ecx # imm = 0xC00
+; X87_LIN-NEXT:    movw %cx, {{[0-9]+}}(%esp)
 ; X87_LIN-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; X87_LIN-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; X87_LIN-NEXT:    fldcw {{[0-9]+}}(%esp)
-; X87_LIN-NEXT:    setbe %dl
+; X87_LIN-NEXT:    movzbl %al, %edx
 ; X87_LIN-NEXT:    shll $31, %edx
 ; X87_LIN-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; X87_LIN-NEXT:    movl {{[0-9]+}}(%esp), %eax
@@ -779,15 +779,15 @@ define i64 @d_to_u64(double %a) nounwind {
 ; X87_WIN-NEXT:    fldz
 ; X87_WIN-NEXT:  LBB2_2:
 ; X87_WIN-NEXT:    fstp %st(0)
+; X87_WIN-NEXT:    setbe %al
 ; X87_WIN-NEXT:    fnstcw {{[0-9]+}}(%esp)
-; X87_WIN-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; X87_WIN-NEXT:    xorl %edx, %edx
-; X87_WIN-NEXT:    orl $3072, %eax # imm = 0xC00
-; X87_WIN-NEXT:    movw %ax, {{[0-9]+}}(%esp)
+; X87_WIN-NEXT:    movzwl {{[0-9]+}}(%esp), %ecx
+; X87_WIN-NEXT:    orl $3072, %ecx # imm = 0xC00
+; X87_WIN-NEXT:    movw %cx, {{[0-9]+}}(%esp)
 ; X87_WIN-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; X87_WIN-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; X87_WIN-NEXT:    fldcw {{[0-9]+}}(%esp)
-; X87_WIN-NEXT:    setbe %dl
+; X87_WIN-NEXT:    movzbl %al, %edx
 ; X87_WIN-NEXT:    shll $31, %edx
 ; X87_WIN-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; X87_WIN-NEXT:    movl {{[0-9]+}}(%esp), %eax
@@ -813,15 +813,15 @@ define i64 @d_to_u64(double %a) nounwind {
 ; X87_LIN-NEXT:    fldz
 ; X87_LIN-NEXT:  .LBB2_2:
 ; X87_LIN-NEXT:    fstp %st(0)
+; X87_LIN-NEXT:    setbe %al
 ; X87_LIN-NEXT:    fnstcw {{[0-9]+}}(%esp)
-; X87_LIN-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; X87_LIN-NEXT:    xorl %edx, %edx
-; X87_LIN-NEXT:    orl $3072, %eax # imm = 0xC00
-; X87_LIN-NEXT:    movw %ax, {{[0-9]+}}(%esp)
+; X87_LIN-NEXT:    movzwl {{[0-9]+}}(%esp), %ecx
+; X87_LIN-NEXT:    orl $3072, %ecx # imm = 0xC00
+; X87_LIN-NEXT:    movw %cx, {{[0-9]+}}(%esp)
 ; X87_LIN-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; X87_LIN-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; X87_LIN-NEXT:    fldcw {{[0-9]+}}(%esp)
-; X87_LIN-NEXT:    setbe %dl
+; X87_LIN-NEXT:    movzbl %al, %edx
 ; X87_LIN-NEXT:    shll $31, %edx
 ; X87_LIN-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; X87_LIN-NEXT:    movl {{[0-9]+}}(%esp), %eax
@@ -1189,19 +1189,19 @@ define i64 @x_to_u64(x86_fp80 %a) nounwind {
 ; SSE2_32_WIN-NEXT:    flds __real@5f000000
 ; SSE2_32_WIN-NEXT:    fld %st(1)
 ; SSE2_32_WIN-NEXT:    fsub %st(1), %st
+; SSE2_32_WIN-NEXT:    xorl %edx, %edx
 ; SSE2_32_WIN-NEXT:    fxch %st(1)
 ; SSE2_32_WIN-NEXT:    fucompi %st(2), %st
 ; SSE2_32_WIN-NEXT:    fcmovnbe %st(1), %st
 ; SSE2_32_WIN-NEXT:    fstp %st(1)
+; SSE2_32_WIN-NEXT:    setbe %dl
 ; SSE2_32_WIN-NEXT:    fnstcw {{[0-9]+}}(%esp)
 ; SSE2_32_WIN-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; SSE2_32_WIN-NEXT:    xorl %edx, %edx
 ; SSE2_32_WIN-NEXT:    orl $3072, %eax # imm = 0xC00
 ; SSE2_32_WIN-NEXT:    movw %ax, {{[0-9]+}}(%esp)
 ; SSE2_32_WIN-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; SSE2_32_WIN-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; SSE2_32_WIN-NEXT:    fldcw {{[0-9]+}}(%esp)
-; SSE2_32_WIN-NEXT:    setbe %dl
 ; SSE2_32_WIN-NEXT:    shll $31, %edx
 ; SSE2_32_WIN-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; SSE2_32_WIN-NEXT:    movl {{[0-9]+}}(%esp), %eax
@@ -1216,19 +1216,19 @@ define i64 @x_to_u64(x86_fp80 %a) nounwind {
 ; SSE2_32_LIN-NEXT:    flds {{\.LCPI.*}}
 ; SSE2_32_LIN-NEXT:    fld %st(1)
 ; SSE2_32_LIN-NEXT:    fsub %st(1), %st
+; SSE2_32_LIN-NEXT:    xorl %edx, %edx
 ; SSE2_32_LIN-NEXT:    fxch %st(1)
 ; SSE2_32_LIN-NEXT:    fucompi %st(2), %st
 ; SSE2_32_LIN-NEXT:    fcmovnbe %st(1), %st
 ; SSE2_32_LIN-NEXT:    fstp %st(1)
+; SSE2_32_LIN-NEXT:    setbe %dl
 ; SSE2_32_LIN-NEXT:    fnstcw {{[0-9]+}}(%esp)
 ; SSE2_32_LIN-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; SSE2_32_LIN-NEXT:    xorl %edx, %edx
 ; SSE2_32_LIN-NEXT:    orl $3072, %eax # imm = 0xC00
 ; SSE2_32_LIN-NEXT:    movw %ax, {{[0-9]+}}(%esp)
 ; SSE2_32_LIN-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; SSE2_32_LIN-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; SSE2_32_LIN-NEXT:    fldcw {{[0-9]+}}(%esp)
-; SSE2_32_LIN-NEXT:    setbe %dl
 ; SSE2_32_LIN-NEXT:    shll $31, %edx
 ; SSE2_32_LIN-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; SSE2_32_LIN-NEXT:    movl {{[0-9]+}}(%esp), %eax
@@ -1242,19 +1242,19 @@ define i64 @x_to_u64(x86_fp80 %a) nounwind {
 ; SSE2_64_WIN-NEXT:    flds __real@{{.*}}(%rip)
 ; SSE2_64_WIN-NEXT:    fld %st(1)
 ; SSE2_64_WIN-NEXT:    fsub %st(1), %st
+; SSE2_64_WIN-NEXT:    xorl %eax, %eax
 ; SSE2_64_WIN-NEXT:    fxch %st(1)
 ; SSE2_64_WIN-NEXT:    fucompi %st(2), %st
 ; SSE2_64_WIN-NEXT:    fcmovnbe %st(1), %st
 ; SSE2_64_WIN-NEXT:    fstp %st(1)
+; SSE2_64_WIN-NEXT:    setbe %al
 ; SSE2_64_WIN-NEXT:    fnstcw {{[0-9]+}}(%rsp)
 ; SSE2_64_WIN-NEXT:    movzwl {{[0-9]+}}(%rsp), %ecx
-; SSE2_64_WIN-NEXT:    xorl %eax, %eax
 ; SSE2_64_WIN-NEXT:    orl $3072, %ecx # imm = 0xC00
 ; SSE2_64_WIN-NEXT:    movw %cx, {{[0-9]+}}(%rsp)
 ; SSE2_64_WIN-NEXT:    fldcw {{[0-9]+}}(%rsp)
 ; SSE2_64_WIN-NEXT:    fistpll {{[0-9]+}}(%rsp)
 ; SSE2_64_WIN-NEXT:    fldcw {{[0-9]+}}(%rsp)
-; SSE2_64_WIN-NEXT:    setbe %al
 ; SSE2_64_WIN-NEXT:    shlq $63, %rax
 ; SSE2_64_WIN-NEXT:    xorq {{[0-9]+}}(%rsp), %rax
 ; SSE2_64_WIN-NEXT:    addq $16, %rsp
@@ -1266,19 +1266,19 @@ define i64 @x_to_u64(x86_fp80 %a) nounwind {
 ; SSE2_64_LIN-NEXT:    flds {{.*}}(%rip)
 ; SSE2_64_LIN-NEXT:    fld %st(1)
 ; SSE2_64_LIN-NEXT:    fsub %st(1), %st
+; SSE2_64_LIN-NEXT:    xorl %eax, %eax
 ; SSE2_64_LIN-NEXT:    fxch %st(1)
 ; SSE2_64_LIN-NEXT:    fucompi %st(2), %st
 ; SSE2_64_LIN-NEXT:    fcmovnbe %st(1), %st
 ; SSE2_64_LIN-NEXT:    fstp %st(1)
+; SSE2_64_LIN-NEXT:    setbe %al
 ; SSE2_64_LIN-NEXT:    fnstcw -{{[0-9]+}}(%rsp)
 ; SSE2_64_LIN-NEXT:    movzwl -{{[0-9]+}}(%rsp), %ecx
-; SSE2_64_LIN-NEXT:    xorl %eax, %eax
 ; SSE2_64_LIN-NEXT:    orl $3072, %ecx # imm = 0xC00
 ; SSE2_64_LIN-NEXT:    movw %cx, -{{[0-9]+}}(%rsp)
 ; SSE2_64_LIN-NEXT:    fldcw -{{[0-9]+}}(%rsp)
 ; SSE2_64_LIN-NEXT:    fistpll -{{[0-9]+}}(%rsp)
 ; SSE2_64_LIN-NEXT:    fldcw -{{[0-9]+}}(%rsp)
-; SSE2_64_LIN-NEXT:    setbe %al
 ; SSE2_64_LIN-NEXT:    shlq $63, %rax
 ; SSE2_64_LIN-NEXT:    xorq -{{[0-9]+}}(%rsp), %rax
 ; SSE2_64_LIN-NEXT:    retq
@@ -1304,15 +1304,15 @@ define i64 @x_to_u64(x86_fp80 %a) nounwind {
 ; X87_WIN-NEXT:    fldz
 ; X87_WIN-NEXT:  LBB4_2:
 ; X87_WIN-NEXT:    fstp %st(0)
+; X87_WIN-NEXT:    setbe %al
 ; X87_WIN-NEXT:    fnstcw {{[0-9]+}}(%esp)
-; X87_WIN-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; X87_WIN-NEXT:    xorl %edx, %edx
-; X87_WIN-NEXT:    orl $3072, %eax # imm = 0xC00
-; X87_WIN-NEXT:    movw %ax, {{[0-9]+}}(%esp)
+; X87_WIN-NEXT:    movzwl {{[0-9]+}}(%esp), %ecx
+; X87_WIN-NEXT:    orl $3072, %ecx # imm = 0xC00
+; X87_WIN-NEXT:    movw %cx, {{[0-9]+}}(%esp)
 ; X87_WIN-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; X87_WIN-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; X87_WIN-NEXT:    fldcw {{[0-9]+}}(%esp)
-; X87_WIN-NEXT:    setbe %dl
+; X87_WIN-NEXT:    movzbl %al, %edx
 ; X87_WIN-NEXT:    shll $31, %edx
 ; X87_WIN-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; X87_WIN-NEXT:    movl {{[0-9]+}}(%esp), %eax
@@ -1338,15 +1338,15 @@ define i64 @x_to_u64(x86_fp80 %a) nounwind {
 ; X87_LIN-NEXT:    fldz
 ; X87_LIN-NEXT:  .LBB4_2:
 ; X87_LIN-NEXT:    fstp %st(0)
+; X87_LIN-NEXT:    setbe %al
 ; X87_LIN-NEXT:    fnstcw {{[0-9]+}}(%esp)
-; X87_LIN-NEXT:    movzwl {{[0-9]+}}(%esp), %eax
-; X87_LIN-NEXT:    xorl %edx, %edx
-; X87_LIN-NEXT:    orl $3072, %eax # imm = 0xC00
-; X87_LIN-NEXT:    movw %ax, {{[0-9]+}}(%esp)
+; X87_LIN-NEXT:    movzwl {{[0-9]+}}(%esp), %ecx
+; X87_LIN-NEXT:    orl $3072, %ecx # imm = 0xC00
+; X87_LIN-NEXT:    movw %cx, {{[0-9]+}}(%esp)
 ; X87_LIN-NEXT:    fldcw {{[0-9]+}}(%esp)
 ; X87_LIN-NEXT:    fistpll {{[0-9]+}}(%esp)
 ; X87_LIN-NEXT:    fldcw {{[0-9]+}}(%esp)
-; X87_LIN-NEXT:    setbe %dl
+; X87_LIN-NEXT:    movzbl %al, %edx
 ; X87_LIN-NEXT:    shll $31, %edx
 ; X87_LIN-NEXT:    xorl {{[0-9]+}}(%esp), %edx
 ; X87_LIN-NEXT:    movl {{[0-9]+}}(%esp), %eax