RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-22 18:54:02 +01:00
Code Issues Projects Releases Wiki Activity

[TargetLowering] expandFP_TO_UINT - avoid FPE due to out of range conversion (PR17686)

Browse Source 
PR17686 demonstrates that for some targets FP exceptions can fire in cases where the FP_TO_UINT is expanded using a FP_TO_SINT instruction.

The existing code converts both the inrange and outofrange cases using FP_TO_SINT and then selects the result, this patch changes this for 'strict' cases to pre-select the FP_TO_SINT input and the offset adjustment.

The X87 cases don't need the strict flag but generates much nicer code with it....

Differential Revision: https://reviews.llvm.org/D53794

llvm-svn: 348251
This commit is contained in:
Simon Pilgrim 2018-12-04 11:21:30 +00:00
parent 5f2f923973
commit 5e25d966f6
6 changed files with 118 additions and 130 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
include/llvm/CodeGen/TargetLowering.h
View File

@ -1746,6 +1746,16 @@ public:
return false;
}
/// Return true if it is more correct/profitable to use strict FP_TO_INT
/// conversion operations - canonicalizing the FP source value instead of
/// converting all cases and then selecting based on value.
/// This may be true if the target throws exceptions for out of bounds
/// conversions or has fast FP CMOV.
virtual bool shouldUseStrictFP_TO_INT(EVT FpVT, EVT IntVT,
bool IsSigned) const {
return false;
}
//===--------------------------------------------------------------------===//
// TargetLowering Configuration Methods - These methods should be invoked by
// the derived class constructor to configure this object for the target.

41
lib/CodeGen/SelectionDAG/TargetLowering.cpp
View File

@ -4200,20 +4200,39 @@ bool TargetLowering::expandFP_TO_UINT(SDNode *Node, SDValue &Result,
return true;
}
// Expand based on maximum range of FP_TO_SINT:
// True = fp_to_sint(Src)
// False = 0x8000000000000000 + fp_to_sint(Src - 0x8000000000000000)
// Result = select (Src < 0x8000000000000000), True, False
SDValue Cst = DAG.getConstantFP(APF, dl, SrcVT);
SDValue Sel = DAG.getSetCC(dl, SetCCVT, Src, Cst, ISD::SETLT);
SDValue True = DAG.getNode(ISD::FP_TO_SINT, dl, DstVT, Src);
// TODO: Should any fast-math-flags be set for the FSUB?
SDValue False = DAG.getNode(ISD::FP_TO_SINT, dl, DstVT,
DAG.getNode(ISD::FSUB, dl, SrcVT, Src, Cst));
False = DAG.getNode(ISD::XOR, dl, DstVT, False,
DAG.getConstant(SignMask, dl, DstVT));
Result = DAG.getSelect(dl, DstVT, Sel, True, False);
bool Strict = shouldUseStrictFP_TO_INT(SrcVT, DstVT, /*IsSigned*/ false);
if (Strict) {
// Expand based on maximum range of FP_TO_SINT, if the value exceeds the
// signmask then offset (the result of which should be fully representable).
// Sel = Src < 0x8000000000000000
// Val = select Sel, Src, Src - 0x8000000000000000
// Ofs = select Sel, 0, 0x8000000000000000
// Result = fp_to_sint(Val) ^ Ofs
// TODO: Should any fast-math-flags be set for the FSUB?
SDValue Val = DAG.getSelect(dl, SrcVT, Sel, Src,
DAG.getNode(ISD::FSUB, dl, SrcVT, Src, Cst));
SDValue Ofs = DAG.getSelect(dl, DstVT, Sel, DAG.getConstant(0, dl, DstVT),
DAG.getConstant(SignMask, dl, DstVT));
Result = DAG.getNode(ISD::XOR, dl, DstVT,
DAG.getNode(ISD::FP_TO_SINT, dl, DstVT, Val), Ofs);
} else {
// Expand based on maximum range of FP_TO_SINT:
// True = fp_to_sint(Src)
// False = 0x8000000000000000 + fp_to_sint(Src - 0x8000000000000000)
// Result = select (Src < 0x8000000000000000), True, False
SDValue True = DAG.getNode(ISD::FP_TO_SINT, dl, DstVT, Src);
// TODO: Should any fast-math-flags be set for the FSUB?
SDValue False = DAG.getNode(ISD::FP_TO_SINT, dl, DstVT,
DAG.getNode(ISD::FSUB, dl, SrcVT, Src, Cst));
False = DAG.getNode(ISD::XOR, dl, DstVT, False,
DAG.getConstant(SignMask, dl, DstVT));
Result = DAG.getSelect(dl, DstVT, Sel, True, False);
}
return true;
}

6
lib/Target/X86/X86ISelLowering.cpp
View File

@ -4812,6 +4812,12 @@ bool X86TargetLowering::decomposeMulByConstant(EVT VT, SDValue C) const {
(1 - MulC).isPowerOf2() || (-(MulC + 1)).isPowerOf2();
}
bool X86TargetLowering::shouldUseStrictFP_TO_INT(EVT FpVT, EVT IntVT,
bool IsSigned) const {
// f80 UINT_TO_FP is more efficient using Strict code if FCMOV is available.
return !IsSigned && FpVT == MVT::f80 && Subtarget.hasCMov();
}
bool X86TargetLowering::isExtractSubvectorCheap(EVT ResVT, EVT SrcVT,
unsigned Index) const {
if (!isOperationLegalOrCustom(ISD::EXTRACT_SUBVECTOR, ResVT))

3
lib/Target/X86/X86ISelLowering.h
View File

@ -1047,6 +1047,9 @@ namespace llvm {
bool decomposeMulByConstant(EVT VT, SDValue C) const override;
bool shouldUseStrictFP_TO_INT(EVT FpVT, EVT IntVT,
bool IsSigned) const override;
/// Return true if EXTRACT_SUBVECTOR is cheap for this result type
/// with this index.
bool isExtractSubvectorCheap(EVT ResVT, EVT SrcVT,

88
test/CodeGen/X86/fp-cvt.ll
View File

@ -483,29 +483,20 @@ 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)
; X64-X87-NEXT: xorl %eax, %eax
; X64-X87-NEXT: fxch %st(1)
; X64-X87-NEXT: fucompi %st(2)
; X64-X87-NEXT: fcmovnbe %st(1), %st(0)
; X64-X87-NEXT: fstp %st(1)
; X64-X87-NEXT: fnstcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movzwl -{{[0-9]+}}(%rsp), %eax
; X64-X87-NEXT: movzwl -{{[0-9]+}}(%rsp), %ecx
; X64-X87-NEXT: movw $3199, -{{[0-9]+}}(%rsp) # imm = 0xC7F
; X64-X87-NEXT: fldcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movw %ax, -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movw %cx, -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fistpll -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fldcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fnstcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movzwl -{{[0-9]+}}(%rsp), %eax
; X64-X87-NEXT: movw $3199, -{{[0-9]+}}(%rsp) # imm = 0xC7F
; X64-X87-NEXT: fldcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movw %ax, -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fld %st(1)
; X64-X87-NEXT: fistpll -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fldcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fucompi %st(1)
; X64-X87-NEXT: fstp %st(0)
; X64-X87-NEXT: jbe .LBB10_1
; X64-X87-NEXT: # %bb.2:
; X64-X87-NEXT: movq -{{[0-9]+}}(%rsp), %rax
; X64-X87-NEXT: retq
; X64-X87-NEXT: .LBB10_1:
; X64-X87-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000
; X64-X87-NEXT: setbe %al
; X64-X87-NEXT: shlq $63, %rax
; X64-X87-NEXT: xorq -{{[0-9]+}}(%rsp), %rax
; X64-X87-NEXT: retq
;
@ -515,17 +506,14 @@ define i64 @fptoui_i64_fp80(x86_fp80 %a0) nounwind {
; X64-SSSE3-NEXT: flds {{.*}}(%rip)
; X64-SSSE3-NEXT: fld %st(1)
; X64-SSSE3-NEXT: fsub %st(1)
; X64-SSSE3-NEXT: xorl %eax, %eax
; X64-SSSE3-NEXT: fxch %st(1)
; X64-SSSE3-NEXT: fucompi %st(2)
; X64-SSSE3-NEXT: fcmovnbe %st(1), %st(0)
; X64-SSSE3-NEXT: fstp %st(1)
; X64-SSSE3-NEXT: fisttpll -{{[0-9]+}}(%rsp)
; X64-SSSE3-NEXT: fld %st(1)
; X64-SSSE3-NEXT: fisttpll -{{[0-9]+}}(%rsp)
; X64-SSSE3-NEXT: fucompi %st(1)
; X64-SSSE3-NEXT: fstp %st(0)
; X64-SSSE3-NEXT: jbe .LBB10_1
; X64-SSSE3-NEXT: # %bb.2:
; X64-SSSE3-NEXT: movq -{{[0-9]+}}(%rsp), %rax
; X64-SSSE3-NEXT: retq
; X64-SSSE3-NEXT: .LBB10_1:
; X64-SSSE3-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000
; X64-SSSE3-NEXT: setbe %al
; X64-SSSE3-NEXT: shlq $63, %rax
; X64-SSSE3-NEXT: xorq -{{[0-9]+}}(%rsp), %rax
; X64-SSSE3-NEXT: retq
%1 = fptoui x86_fp80 %a0 to i64
@ -577,29 +565,20 @@ 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)
; X64-X87-NEXT: xorl %eax, %eax
; X64-X87-NEXT: fxch %st(1)
; X64-X87-NEXT: fucompi %st(2)
; X64-X87-NEXT: fcmovnbe %st(1), %st(0)
; X64-X87-NEXT: fstp %st(1)
; X64-X87-NEXT: fnstcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movzwl -{{[0-9]+}}(%rsp), %eax
; X64-X87-NEXT: movzwl -{{[0-9]+}}(%rsp), %ecx
; X64-X87-NEXT: movw $3199, -{{[0-9]+}}(%rsp) # imm = 0xC7F
; X64-X87-NEXT: fldcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movw %ax, -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movw %cx, -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fistpll -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fldcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fnstcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movzwl -{{[0-9]+}}(%rsp), %eax
; X64-X87-NEXT: movw $3199, -{{[0-9]+}}(%rsp) # imm = 0xC7F
; X64-X87-NEXT: fldcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: movw %ax, -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fld %st(1)
; X64-X87-NEXT: fistpll -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fldcw -{{[0-9]+}}(%rsp)
; X64-X87-NEXT: fucompi %st(1)
; X64-X87-NEXT: fstp %st(0)
; X64-X87-NEXT: jbe .LBB11_1
; X64-X87-NEXT: # %bb.2:
; X64-X87-NEXT: movq -{{[0-9]+}}(%rsp), %rax
; X64-X87-NEXT: retq
; X64-X87-NEXT: .LBB11_1:
; X64-X87-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000
; X64-X87-NEXT: setbe %al
; X64-X87-NEXT: shlq $63, %rax
; X64-X87-NEXT: xorq -{{[0-9]+}}(%rsp), %rax
; X64-X87-NEXT: retq
;
@ -609,17 +588,14 @@ define i64 @fptoui_i64_fp80_ld(x86_fp80 *%a0) nounwind {
; X64-SSSE3-NEXT: flds {{.*}}(%rip)
; X64-SSSE3-NEXT: fld %st(1)
; X64-SSSE3-NEXT: fsub %st(1)
; X64-SSSE3-NEXT: xorl %eax, %eax
; X64-SSSE3-NEXT: fxch %st(1)
; X64-SSSE3-NEXT: fucompi %st(2)
; X64-SSSE3-NEXT: fcmovnbe %st(1), %st(0)
; X64-SSSE3-NEXT: fstp %st(1)
; X64-SSSE3-NEXT: fisttpll -{{[0-9]+}}(%rsp)
; X64-SSSE3-NEXT: fld %st(1)
; X64-SSSE3-NEXT: fisttpll -{{[0-9]+}}(%rsp)
; X64-SSSE3-NEXT: fucompi %st(1)
; X64-SSSE3-NEXT: fstp %st(0)
; X64-SSSE3-NEXT: jbe .LBB11_1
; X64-SSSE3-NEXT: # %bb.2:
; X64-SSSE3-NEXT: movq -{{[0-9]+}}(%rsp), %rax
; X64-SSSE3-NEXT: retq
; X64-SSSE3-NEXT: .LBB11_1:
; X64-SSSE3-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000
; X64-SSSE3-NEXT: setbe %al
; X64-SSSE3-NEXT: shlq $63, %rax
; X64-SSSE3-NEXT: xorq -{{[0-9]+}}(%rsp), %rax
; X64-SSSE3-NEXT: retq
%1 = load x86_fp80, x86_fp80 *%a0

100
test/CodeGen/X86/scalar-fp-to-i64.ll
View File

@ -1147,25 +1147,21 @@ define i64 @x_to_u64(x86_fp80 %a) nounwind {
;
; SSE3_64_WIN-LABEL: x_to_u64:
; SSE3_64_WIN: # %bb.0:
; SSE3_64_WIN-NEXT: subq $16, %rsp
; SSE3_64_WIN-NEXT: pushq %rax
; SSE3_64_WIN-NEXT: fldt (%rcx)
; SSE3_64_WIN-NEXT: flds __real@{{.*}}(%rip)
; SSE3_64_WIN-NEXT: fld %st(1)
; SSE3_64_WIN-NEXT: fsub %st(1)
; SSE3_64_WIN-NEXT: fisttpll {{[0-9]+}}(%rsp)
; SSE3_64_WIN-NEXT: fld %st(1)
; SSE3_64_WIN-NEXT: xorl %eax, %eax
; SSE3_64_WIN-NEXT: fxch %st(1)
; SSE3_64_WIN-NEXT: fucompi %st(2)
; SSE3_64_WIN-NEXT: fcmovnbe %st(1), %st(0)
; SSE3_64_WIN-NEXT: fstp %st(1)
; SSE3_64_WIN-NEXT: fisttpll (%rsp)
; SSE3_64_WIN-NEXT: fucompi %st(1)
; SSE3_64_WIN-NEXT: fstp %st(0)
; SSE3_64_WIN-NEXT: jbe .LBB4_1
; SSE3_64_WIN-NEXT: # %bb.2:
; SSE3_64_WIN-NEXT: movq (%rsp), %rax
; SSE3_64_WIN-NEXT: addq $16, %rsp
; SSE3_64_WIN-NEXT: retq
; SSE3_64_WIN-NEXT: .LBB4_1:
; SSE3_64_WIN-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000
; SSE3_64_WIN-NEXT: xorq {{[0-9]+}}(%rsp), %rax
; SSE3_64_WIN-NEXT: addq $16, %rsp
; SSE3_64_WIN-NEXT: setbe %al
; SSE3_64_WIN-NEXT: shlq $63, %rax
; SSE3_64_WIN-NEXT: xorq (%rsp), %rax
; SSE3_64_WIN-NEXT: popq %rcx
; SSE3_64_WIN-NEXT: retq
;
; SSE3_64_LIN-LABEL: x_to_u64:
@ -1174,17 +1170,14 @@ define i64 @x_to_u64(x86_fp80 %a) nounwind {
; SSE3_64_LIN-NEXT: flds {{.*}}(%rip)
; SSE3_64_LIN-NEXT: fld %st(1)
; SSE3_64_LIN-NEXT: fsub %st(1)
; SSE3_64_LIN-NEXT: xorl %eax, %eax
; SSE3_64_LIN-NEXT: fxch %st(1)
; SSE3_64_LIN-NEXT: fucompi %st(2)
; SSE3_64_LIN-NEXT: fcmovnbe %st(1), %st(0)
; SSE3_64_LIN-NEXT: fstp %st(1)
; SSE3_64_LIN-NEXT: fisttpll -{{[0-9]+}}(%rsp)
; SSE3_64_LIN-NEXT: fld %st(1)
; SSE3_64_LIN-NEXT: fisttpll -{{[0-9]+}}(%rsp)
; SSE3_64_LIN-NEXT: fucompi %st(1)
; SSE3_64_LIN-NEXT: fstp %st(0)
; SSE3_64_LIN-NEXT: jbe .LBB4_1
; SSE3_64_LIN-NEXT: # %bb.2:
; SSE3_64_LIN-NEXT: movq -{{[0-9]+}}(%rsp), %rax
; SSE3_64_LIN-NEXT: retq
; SSE3_64_LIN-NEXT: .LBB4_1:
; SSE3_64_LIN-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000
; SSE3_64_LIN-NEXT: setbe %al
; SSE3_64_LIN-NEXT: shlq $63, %rax
; SSE3_64_LIN-NEXT: xorq -{{[0-9]+}}(%rsp), %rax
; SSE3_64_LIN-NEXT: retq
;
@ -1246,37 +1239,27 @@ define i64 @x_to_u64(x86_fp80 %a) nounwind {
;
; SSE2_64_WIN-LABEL: x_to_u64:
; SSE2_64_WIN: # %bb.0:
; SSE2_64_WIN-NEXT: subq $24, %rsp
; SSE2_64_WIN-NEXT: subq $16, %rsp
; SSE2_64_WIN-NEXT: fldt (%rcx)
; SSE2_64_WIN-NEXT: flds __real@{{.*}}(%rip)
; SSE2_64_WIN-NEXT: fld %st(1)
; SSE2_64_WIN-NEXT: fsub %st(1)
; SSE2_64_WIN-NEXT: xorl %eax, %eax
; SSE2_64_WIN-NEXT: fxch %st(1)
; SSE2_64_WIN-NEXT: fucompi %st(2)
; SSE2_64_WIN-NEXT: fcmovnbe %st(1), %st(0)
; SSE2_64_WIN-NEXT: fstp %st(1)
; SSE2_64_WIN-NEXT: fnstcw {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: movzwl {{[0-9]+}}(%rsp), %eax
; SSE2_64_WIN-NEXT: movzwl {{[0-9]+}}(%rsp), %ecx
; SSE2_64_WIN-NEXT: movw $3199, {{[0-9]+}}(%rsp) # imm = 0xC7F
; SSE2_64_WIN-NEXT: fldcw {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: movw %ax, {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: movw %cx, {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: fistpll {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: fldcw {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: fnstcw {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: movzwl {{[0-9]+}}(%rsp), %eax
; SSE2_64_WIN-NEXT: movw $3199, {{[0-9]+}}(%rsp) # imm = 0xC7F
; SSE2_64_WIN-NEXT: fldcw {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: movw %ax, {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: fld %st(1)
; SSE2_64_WIN-NEXT: fistpll {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: fldcw {{[0-9]+}}(%rsp)
; SSE2_64_WIN-NEXT: fucompi %st(1)
; SSE2_64_WIN-NEXT: fstp %st(0)
; SSE2_64_WIN-NEXT: jbe .LBB4_1
; SSE2_64_WIN-NEXT: # %bb.2:
; SSE2_64_WIN-NEXT: movq {{[0-9]+}}(%rsp), %rax
; SSE2_64_WIN-NEXT: addq $24, %rsp
; SSE2_64_WIN-NEXT: retq
; SSE2_64_WIN-NEXT: .LBB4_1:
; SSE2_64_WIN-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000
; 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 $24, %rsp
; SSE2_64_WIN-NEXT: addq $16, %rsp
; SSE2_64_WIN-NEXT: retq
;
; SSE2_64_LIN-LABEL: x_to_u64:
@ -1285,29 +1268,20 @@ 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)
; SSE2_64_LIN-NEXT: xorl %eax, %eax
; SSE2_64_LIN-NEXT: fxch %st(1)
; SSE2_64_LIN-NEXT: fucompi %st(2)
; SSE2_64_LIN-NEXT: fcmovnbe %st(1), %st(0)
; SSE2_64_LIN-NEXT: fstp %st(1)
; SSE2_64_LIN-NEXT: fnstcw -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: movzwl -{{[0-9]+}}(%rsp), %eax
; SSE2_64_LIN-NEXT: movzwl -{{[0-9]+}}(%rsp), %ecx
; SSE2_64_LIN-NEXT: movw $3199, -{{[0-9]+}}(%rsp) # imm = 0xC7F
; SSE2_64_LIN-NEXT: fldcw -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: movw %ax, -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: movw %cx, -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: fistpll -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: fldcw -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: fnstcw -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: movzwl -{{[0-9]+}}(%rsp), %eax
; SSE2_64_LIN-NEXT: movw $3199, -{{[0-9]+}}(%rsp) # imm = 0xC7F
; SSE2_64_LIN-NEXT: fldcw -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: movw %ax, -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: fld %st(1)
; SSE2_64_LIN-NEXT: fistpll -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: fldcw -{{[0-9]+}}(%rsp)
; SSE2_64_LIN-NEXT: fucompi %st(1)
; SSE2_64_LIN-NEXT: fstp %st(0)
; SSE2_64_LIN-NEXT: jbe .LBB4_1
; SSE2_64_LIN-NEXT: # %bb.2:
; SSE2_64_LIN-NEXT: movq -{{[0-9]+}}(%rsp), %rax
; SSE2_64_LIN-NEXT: retq
; SSE2_64_LIN-NEXT: .LBB4_1:
; SSE2_64_LIN-NEXT: movabsq $-9223372036854775808, %rax # imm = 0x8000000000000000
; 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
;