Michael J. Spencer d4b4f2d340 [IR] Make {extract,insert}element accept an index of any integer type. ... Given the following C code llvm currently generates suboptimal code for x86-64: __m128 bss4( const __m128 *ptr, size_t i, size_t j ) { float f = ptr[i][j]; return (__m128) { f, f, f, f }; } ================================================= define <4 x float> @_Z4bss4PKDv4_fmm(<4 x float>* nocapture readonly %ptr, i64 %i, i64 %j) #0 { %a1 = getelementptr inbounds <4 x float>* %ptr, i64 %i %a2 = load <4 x float>* %a1, align 16, !tbaa !1 %a3 = trunc i64 %j to i32 %a4 = extractelement <4 x float> %a2, i32 %a3 %a5 = insertelement <4 x float> undef, float %a4, i32 0 %a6 = insertelement <4 x float> %a5, float %a4, i32 1 %a7 = insertelement <4 x float> %a6, float %a4, i32 2 %a8 = insertelement <4 x float> %a7, float %a4, i32 3 ret <4 x float> %a8 } ================================================= shlq $4, %rsi addq %rdi, %rsi movslq %edx, %rax vbroadcastss (%rsi,%rax,4), %xmm0 retq ================================================= The movslq is uneeded, but is present because of the trunc to i32 and then sext back to i64 that the backend adds for vbroadcastss. We can't remove it because it changes the meaning. The IR that clang generates is already suboptimal. What clang really should emit is: %a4 = extractelement <4 x float> %a2, i64 %j This patch makes that legal. A separate patch will teach clang to do it. Differential Revision: http://reviews.llvm.org/D3519 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207801 91177308-0d34-0410-b5e6-96231b3b80d8		2014-05-01 22:12:39 +00:00
..
BitcodeWriter.cpp	[IR] Make {extract,insert}element accept an index of any integer type.	2014-05-01 22:12:39 +00:00
BitcodeWriterPass.cpp
BitWriter.cpp
CMakeLists.txt
LLVMBuild.txt
Makefile
ValueEnumerator.cpp
ValueEnumerator.h