From 2e0d5f84325303fa95997cd66485811bd0a6ef70 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Sat, 31 Jan 2009 02:28:54 +0000 Subject: Simplify and generalize the SROA "convert to scalar" transformation to be able to handle *ANY* alloca that is poked by loads and stores of bitcasts and GEPs with constant offsets. Before the code had a number of annoying limitations and caused it to miss cases such as storing into holes in structs and complex casts (as in bitfield-sroa) where we had unions of bitfields etc. This also handles a number of important cases that are exposed due to the ABI lowering stuff we do to pass stuff by value. One case that is pretty great is that we compile 2006-11-07-InvalidArrayPromote.ll into: define i32 @func(<4 x float> %v0, <4 x float> %v1) nounwind { %tmp10 = call <4 x i32> @llvm.x86.sse2.cvttps2dq(<4 x float> %v1) %tmp105 = bitcast <4 x i32> %tmp10 to i128 %tmp1056 = zext i128 %tmp105 to i256 %tmp.upgrd.43 = lshr i256 %tmp1056, 96 %tmp.upgrd.44 = trunc i256 %tmp.upgrd.43 to i32 ret i32 %tmp.upgrd.44 } which turns into: _func: subl $28, %esp cvttps2dq %xmm1, %xmm0 movaps %xmm0, (%esp) movl 12(%esp), %eax addl $28, %esp ret Which is pretty good code all things considering :). One effect of this is that SROA will start generating arbitrary bitwidth integers that are a multiple of 8 bits. In the case above, we got a 256 bit integer, but the codegen guys assure me that it can handle the simple and/or/shift/zext stuff that we're doing on these operations. This addresses rdar://6532315 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63469 91177308-0d34-0410-b5e6-96231b3b80d8 --- test/Transforms/ScalarRepl/2003-05-29-ArrayFail.ll | 7 +++---- .../ScalarRepl/2006-11-07-InvalidArrayPromote.ll | 5 ++--- test/Transforms/ScalarRepl/badarray.ll | 2 +- test/Transforms/ScalarRepl/bitfield-sroa.ll | 16 ++++++++++++++++ 4 files changed, 22 insertions(+), 8 deletions(-) create mode 100644 test/Transforms/ScalarRepl/bitfield-sroa.ll (limited to 'test/Transforms/ScalarRepl') diff --git a/test/Transforms/ScalarRepl/2003-05-29-ArrayFail.ll b/test/Transforms/ScalarRepl/2003-05-29-ArrayFail.ll index adfa5f8..4b7d622 100644 --- a/test/Transforms/ScalarRepl/2003-05-29-ArrayFail.ll +++ b/test/Transforms/ScalarRepl/2003-05-29-ArrayFail.ll @@ -1,9 +1,8 @@ -; RUN: llvm-as < %s | opt -scalarrepl | llvm-dis | \ -; RUN: grep alloca | grep {4 x} +; RUN: llvm-as < %s | opt -scalarrepl | llvm-dis | grep {ret i32 undef} -; Test that an array is not incorrectly deconstructed... +; Test that an array is not incorrectly deconstructed. -define i32 @test() { +define i32 @test() nounwind { %X = alloca [4 x i32] ; <[4 x i32]*> [#uses=1] %Y = getelementptr [4 x i32]* %X, i64 0, i64 0 ; [#uses=1] ; Must preserve arrayness! diff --git a/test/Transforms/ScalarRepl/2006-11-07-InvalidArrayPromote.ll b/test/Transforms/ScalarRepl/2006-11-07-InvalidArrayPromote.ll index 1f3df49..f0253b7 100644 --- a/test/Transforms/ScalarRepl/2006-11-07-InvalidArrayPromote.ll +++ b/test/Transforms/ScalarRepl/2006-11-07-InvalidArrayPromote.ll @@ -1,7 +1,6 @@ -; RUN: llvm-as < %s | opt -scalarrepl | llvm-dis | \ -; RUN: grep -F {alloca \[2 x <4 x i32>\]} +; RUN: llvm-as < %s | opt -scalarrepl | llvm-dis | not grep alloca -define i32 @func(<4 x float> %v0, <4 x float> %v1) { +define i32 @func(<4 x float> %v0, <4 x float> %v1) nounwind { %vsiidx = alloca [2 x <4 x i32>], align 16 ; <[2 x <4 x i32>]*> [#uses=3] %tmp = call <4 x i32> @llvm.x86.sse2.cvttps2dq( <4 x float> %v0 ) ; <<4 x i32>> [#uses=2] %tmp.upgrd.1 = bitcast <4 x i32> %tmp to <2 x i64> ; <<2 x i64>> [#uses=0] diff --git a/test/Transforms/ScalarRepl/badarray.ll b/test/Transforms/ScalarRepl/badarray.ll index 1e4714e..56ae04c 100644 --- a/test/Transforms/ScalarRepl/badarray.ll +++ b/test/Transforms/ScalarRepl/badarray.ll @@ -1,4 +1,4 @@ -; RUN: llvm-as < %s | opt -scalarrepl -mem2reg | llvm-dis | grep alloca +; RUN: llvm-as < %s | opt -scalarrepl -instcombine | llvm-dis | grep {ret i32 0} define i32 @test() { %X = alloca [4 x i32] ; <[4 x i32]*> [#uses=1] diff --git a/test/Transforms/ScalarRepl/bitfield-sroa.ll b/test/Transforms/ScalarRepl/bitfield-sroa.ll new file mode 100644 index 0000000..34dd120 --- /dev/null +++ b/test/Transforms/ScalarRepl/bitfield-sroa.ll @@ -0,0 +1,16 @@ +; RUN: llvm-as < %s | opt -scalarrepl | llvm-dis | not grep alloca +; rdar://6532315 +%t = type { { i32, i16, i8, i8 } } + +define i8 @foo(i64 %A) { + %ALL = alloca %t, align 8 + %tmp59172 = bitcast %t* %ALL to i64* + store i64 %A, i64* %tmp59172, align 8 + %C = getelementptr %t* %ALL, i32 0, i32 0, i32 1 + %D = bitcast i16* %C to i32* + %E = load i32* %D, align 4 + %F = bitcast %t* %ALL to i8* + %G = load i8* %F, align 8 + ret i8 %G +} + -- cgit v1.1