llvm-mirror/test/CodeGen/X86/dagcombine-cse.ll
Elena Demikhovsky 6b2fa94db0 Optimized instruction sequence for sitofp operation on X86-32
Optimized sitofp i64 %x to double. The current sequence

movl %ecx, 8(%esp) 
movl %edx, 12(%esp) 
fildll 8(%esp)

is replaced with:

movd %ecx, %xmm0 
movd %edx, %xmm1 
punpckldq %xmm1, %xmm0 
movq %xmm0, 8(%esp)

Differential Revision: http://reviews.llvm.org/D15946

llvm-svn: 257285
2016-01-10 09:41:22 +00:00

29 lines
1.7 KiB
LLVM

; REQUIRES: asserts
; RUN: llc < %s -march=x86 -mattr=+sse2 -mtriple=i386-apple-darwin -stats 2>&1 | grep asm-printer | grep 13
define i32 @t(i8* %ref_frame_ptr, i32 %ref_frame_stride, i32 %idxX, i32 %idxY) nounwind {
entry:
%tmp7 = mul i32 %idxY, %ref_frame_stride ; <i32> [#uses=2]
%tmp9 = add i32 %tmp7, %idxX ; <i32> [#uses=1]
%tmp11 = getelementptr i8, i8* %ref_frame_ptr, i32 %tmp9 ; <i8*> [#uses=1]
%tmp1112 = bitcast i8* %tmp11 to i32* ; <i32*> [#uses=1]
%tmp13 = load i32, i32* %tmp1112, align 4 ; <i32> [#uses=1]
%tmp18 = add i32 %idxX, 4 ; <i32> [#uses=1]
%tmp20.sum = add i32 %tmp18, %tmp7 ; <i32> [#uses=1]
%tmp21 = getelementptr i8, i8* %ref_frame_ptr, i32 %tmp20.sum ; <i8*> [#uses=1]
%tmp2122 = bitcast i8* %tmp21 to i16* ; <i16*> [#uses=1]
%tmp23 = load i16, i16* %tmp2122, align 2 ; <i16> [#uses=1]
%tmp2425 = zext i16 %tmp23 to i64 ; <i64> [#uses=1]
%tmp26 = shl i64 %tmp2425, 32 ; <i64> [#uses=1]
%tmp2728 = zext i32 %tmp13 to i64 ; <i64> [#uses=1]
%tmp29 = or i64 %tmp26, %tmp2728 ; <i64> [#uses=1]
%tmp3454 = bitcast i64 %tmp29 to double ; <double> [#uses=1]
%tmp35 = insertelement <2 x double> undef, double %tmp3454, i32 0 ; <<2 x double>> [#uses=1]
%tmp36 = insertelement <2 x double> %tmp35, double 0.000000e+00, i32 1 ; <<2 x double>> [#uses=1]
%tmp42 = bitcast <2 x double> %tmp36 to <8 x i16> ; <<8 x i16>> [#uses=1]
%tmp43 = shufflevector <8 x i16> %tmp42, <8 x i16> undef, <8 x i32> < i32 0, i32 1, i32 1, i32 2, i32 4, i32 5, i32 6, i32 7 > ; <<8 x i16>> [#uses=1]
%tmp47 = bitcast <8 x i16> %tmp43 to <4 x i32> ; <<4 x i32>> [#uses=1]
%tmp48 = extractelement <4 x i32> %tmp47, i32 0 ; <i32> [#uses=1]
ret i32 %tmp48
}