llvm-6502/test/CodeGen/X86/uint_to_fp.ll

; RUN: llvm-as < %s | llc -march=x86 -mcpu=yonah | not grep {sub.*esp}
; rdar://6034396

target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
target triple = "i386-apple-darwin8"

define void @test(i32 %x, float* %y) nounwind  {
entry:
	lshr i32 %x, 23		; <i32>:0 [#uses=1]
	uitofp i32 %0 to float		; <float>:1 [#uses=1]
	store float %1, float* %y
	ret void
}
when we know the signbit of an input to uint_to_fp is zero, change it to sint_to_fp on targets where that is cheaper (and visaversa of course). This allows us to compile uint_to_fp to: _test: movl 4(%esp), %eax shrl $23, %eax cvtsi2ss %eax, %xmm0 movl 8(%esp), %eax movss %xmm0, (%eax) ret instead of: .align 3 LCPI1_0: ## double .long 0 ## double least significant word 4.5036e+15 .long 1127219200 ## double most significant word 4.5036e+15 .text .align 4,0x90 .globl _test _test: subl $12, %esp movl 16(%esp), %eax shrl $23, %eax movl %eax, (%esp) movl $1127219200, 4(%esp) movsd (%esp), %xmm0 subsd LCPI1_0, %xmm0 cvtsd2ss %xmm0, %xmm0 movl 20(%esp), %eax movss %xmm0, (%eax) addl $12, %esp ret git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52747 91177308-0d34-0410-b5e6-96231b3b80d8 2008-06-26 00:16:49 +00:00			`; RUN: llvm-as < %s \| llc -march=x86 -mcpu=yonah \| not grep {sub.*esp}`
			`; rdar://6034396`

			`target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"`
			`target triple = "i386-apple-darwin8"`

			`define void @test(i32 %x, float* %y) nounwind {`
			`entry:`
			`lshr i32 %x, 23 ; <i32>:0 [#uses=1]`
			`uitofp i32 %0 to float ; <float>:1 [#uses=1]`
			`store float %1, float* %y`
			`ret void`
			`}`