Make X86TargetLowering::LowerSINT_TO_FP return without creating a dead

stack slot and store if the  SINT_TO_FP is actually legal.  This allows
us to compile:

double a(double b) {return (unsigned)b;}

to:

_a:
	cvttsd2siq	%xmm0, %rax
	movl	%eax, %eax
	cvtsi2sdq	%rax, %xmm0
	ret

instead of:

_a:
	subq	$8, %rsp
	cvttsd2siq	%xmm0, %rax
	movl	%eax, %eax
	cvtsi2sdq	%rax, %xmm0
	addq	$8, %rsp
	ret

crazy.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47660 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 0 insertions, 15 deletions

diff --git a/lib/Target/X86/README-X86-64.txt b/lib/Target/X86/README-X86-64.txt
index efe3b73da5..359b83d01a 100644
--- a/lib/Target/X86/README-X86-64.txt
+++ b/lib/Target/X86/README-X86-64.txt
@@ -236,18 +236,3 @@ on the result of the movb).
 
 //===---------------------------------------------------------------------===//
 
-This function:
-double a(double b) {return (unsigned)b;} 
-compiles to this code:
-
-_a:
-	subq	$8, %rsp
-	cvttsd2siq	%xmm0, %rax
-	movl	%eax, %eax
-	cvtsi2sdq	%rax, %xmm0
-	addq	$8, %rsp
-	ret
-
-note the dead rsp adjustments.
-
-//===---------------------------------------------------------------------===//