From 50f1f9435ae3fee97cbc4b6f618d1b5648edd44d Mon Sep 17 00:00:00 2001 From: Hiroshi Inoue Date: Thu, 30 Nov 2017 08:29:51 +0000 Subject: [PATCH] Revert rL319407: [SROA] enable splitting for non-whole-alloca loads and stores This reverts commit rL319407 due to failures in some buildbot. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319410 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/SROA.cpp | 31 ++++++++++------------------- test/DebugInfo/X86/sroasplit-2.ll | 3 +-- test/Transforms/SROA/basictest.ll | 33 ++++--------------------------- test/Transforms/SROA/big-endian.ll | 40 ++++++++++++-------------------------- 4 files changed, 27 insertions(+), 80 deletions(-) diff --git a/lib/Transforms/Scalar/SROA.cpp b/lib/Transforms/Scalar/SROA.cpp index d0431d48a43..bd064978b64 100644 --- a/lib/Transforms/Scalar/SROA.cpp +++ b/lib/Transforms/Scalar/SROA.cpp @@ -30,7 +30,6 @@ #include "llvm/ADT/PointerIntPair.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/SetVector.h" -#include "llvm/ADT/SmallBitVector.h" #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/Statistic.h" @@ -4048,31 +4047,21 @@ bool SROA::splitAlloca(AllocaInst &AI, AllocaSlices &AS) { // First try to pre-split loads and stores. Changed |= presplitLoadsAndStores(AI, AS); - // Now that we have identified any pre-splitting opportunities, - // mark loads and stores unsplittable except for the following case. - // We leave a slice splittable if all other slices are disjoint or fully - // included in the slice, such as whole-alloca loads and stores. - // If we fail to split these during pre-splitting, we want to force them - // to be rewritten into a partition. + // Now that we have identified any pre-splitting opportunities, mark any + // splittable (non-whole-alloca) loads and stores as unsplittable. If we fail + // to split these during pre-splitting, we want to force them to be + // rewritten into a partition. bool IsSorted = true; - - // If a byte boundary is included in any load or store, a slice starting or - // ending at the boundary is not splittable. - unsigned AllocaSize = DL.getTypeAllocSize(AI.getAllocatedType()); - SmallBitVector SplittableOffset(AllocaSize+1, true); - for (Slice &S : AS) - for (unsigned O = S.beginOffset() + 1; O < S.endOffset() && O < AllocaSize; - O++) - SplittableOffset.reset(O); - for (Slice &S : AS) { if (!S.isSplittable()) continue; - - if ((S.beginOffset() > AllocaSize || SplittableOffset[S.beginOffset()]) && - (S.endOffset() > AllocaSize || SplittableOffset[S.endOffset()])) + // FIXME: We currently leave whole-alloca splittable loads and stores. This + // used to be the only splittable loads and stores and we need to be + // confident that the above handling of splittable loads and stores is + // completely sufficient before we forcibly disable the remaining handling. + if (S.beginOffset() == 0 && + S.endOffset() >= DL.getTypeAllocSize(AI.getAllocatedType())) continue; - if (isa(S.getUse()->getUser()) || isa(S.getUse()->getUser())) { S.makeUnsplittable(); diff --git a/test/DebugInfo/X86/sroasplit-2.ll b/test/DebugInfo/X86/sroasplit-2.ll index 3e99ec1e16a..b2bec7cede0 100644 --- a/test/DebugInfo/X86/sroasplit-2.ll +++ b/test/DebugInfo/X86/sroasplit-2.ll @@ -21,8 +21,7 @@ ; Verify that SROA creates a variable piece when splitting i1. ; CHECK: call void @llvm.dbg.value(metadata i64 %outer.coerce0, metadata ![[O:[0-9]+]], metadata !DIExpression(DW_OP_LLVM_fragment, 0, 64)), -; CHECK: call void @llvm.dbg.value(metadata i32 {{.*}}, metadata ![[O]], metadata !DIExpression(DW_OP_LLVM_fragment, 64, 32)), -; CHECK: call void @llvm.dbg.value(metadata i32 {{.*}}, metadata ![[O]], metadata !DIExpression(DW_OP_LLVM_fragment, 96, 32)), +; CHECK: call void @llvm.dbg.value(metadata i64 %outer.coerce1, metadata ![[O]], metadata !DIExpression(DW_OP_LLVM_fragment, 64, 64)), ; CHECK: call void @llvm.dbg.value({{.*}}, metadata ![[I1:[0-9]+]], metadata !DIExpression(DW_OP_LLVM_fragment, 0, 32)), ; CHECK-DAG: ![[O]] = !DILocalVariable(name: "outer",{{.*}} line: 10 ; CHECK-DAG: ![[I1]] = !DILocalVariable(name: "i1",{{.*}} line: 11 diff --git a/test/Transforms/SROA/basictest.ll b/test/Transforms/SROA/basictest.ll index 9cf21910a5f..aa00e89ea04 100644 --- a/test/Transforms/SROA/basictest.ll +++ b/test/Transforms/SROA/basictest.ll @@ -1615,13 +1615,13 @@ define i16 @PR24463() { ; Ensure we can handle a very interesting case where there is an integer-based ; rewrite of the uses of the alloca, but where one of the integers in that is ; a sub-integer that requires extraction *and* extends past the end of the -; alloca. SROA can split the alloca to avoid shift or trunc. +; alloca. In this case, we should extract the i8 and then zext it to i16. ; ; CHECK-LABEL: @PR24463( ; CHECK-NOT: alloca -; CHECK-NOT: trunc -; CHECK-NOT: lshr -; CHECK: %[[ZEXT:.*]] = zext i8 {{.*}} to i16 +; CHECK: %[[SHIFT:.*]] = lshr i16 0, 8 +; CHECK: %[[TRUNC:.*]] = trunc i16 %[[SHIFT]] to i8 +; CHECK: %[[ZEXT:.*]] = zext i8 %[[TRUNC]] to i16 ; CHECK: ret i16 %[[ZEXT]] entry: %alloca = alloca [3 x i8] @@ -1695,28 +1695,3 @@ bb1: call void @llvm.lifetime.end.p0i8(i64 2, i8* %0) ret void } - -define void @test28(i64 %v) #0 { -; SROA should split the first i64 store to avoid additional and/or instructions -; when storing into i32 fields - -; CHECK-LABEL: @test28( -; CHECK-NOT: alloca -; CHECK-NOT: and -; CHECK-NOT: or -; CHECK: %[[shift:.*]] = lshr i64 %v, 32 -; CHECK-NEXT: %{{.*}} = trunc i64 %[[shift]] to i32 -; CHECK-NEXT: ret void - -entry: - %t = alloca { i64, i32, i32 } - - %b = getelementptr { i64, i32, i32 }, { i64, i32, i32 }* %t, i32 0, i32 1 - %0 = bitcast i32* %b to i64* - store i64 %v, i64* %0 - - %1 = load i32, i32* %b - %c = getelementptr { i64, i32, i32 }, { i64, i32, i32 }* %t, i32 0, i32 2 - store i32 %1, i32* %c - ret void -} diff --git a/test/Transforms/SROA/big-endian.ll b/test/Transforms/SROA/big-endian.ll index fc4b8b28855..ea41a20fd38 100644 --- a/test/Transforms/SROA/big-endian.ll +++ b/test/Transforms/SROA/big-endian.ll @@ -83,34 +83,19 @@ entry: store i16 1, i16* %a0i16ptr store i8 1, i8* %a2ptr +; CHECK: %[[mask1:.*]] = and i40 undef, 4294967295 +; CHECK-NEXT: %[[insert1:.*]] = or i40 %[[mask1]], 4294967296 %a3i24ptr = bitcast i8* %a3ptr to i24* store i24 1, i24* %a3i24ptr +; CHECK-NEXT: %[[mask2:.*]] = and i40 %[[insert1]], -4294967041 +; CHECK-NEXT: %[[insert2:.*]] = or i40 %[[mask2]], 256 %a2i40ptr = bitcast i8* %a2ptr to i40* store i40 1, i40* %a2i40ptr - -; the alloca is splitted into multiple slices -; Here, i8 1 is for %a[6] -; CHECK: %[[ext1:.*]] = zext i8 1 to i40 -; CHECK-NEXT: %[[mask1:.*]] = and i40 undef, -256 -; CHECK-NEXT: %[[insert1:.*]] = or i40 %[[mask1]], %[[ext1]] - -; Here, i24 0 is for %a[3] to %a[5] -; CHECK-NEXT: %[[ext2:.*]] = zext i24 0 to i40 -; CHECK-NEXT: %[[shift2:.*]] = shl i40 %[[ext2]], 8 -; CHECK-NEXT: %[[mask2:.*]] = and i40 %[[insert1]], -4294967041 -; CHECK-NEXT: %[[insert2:.*]] = or i40 %[[mask2]], %[[shift2]] - -; Here, i8 0 is for %a[2] -; CHECK-NEXT: %[[ext3:.*]] = zext i8 0 to i40 -; CHECK-NEXT: %[[shift3:.*]] = shl i40 %[[ext3]], 32 -; CHECK-NEXT: %[[mask3:.*]] = and i40 %[[insert2]], 4294967295 -; CHECK-NEXT: %[[insert3:.*]] = or i40 %[[mask3]], %[[shift3]] - -; CHECK-NEXT: %[[ext4:.*]] = zext i40 %[[insert3]] to i56 -; CHECK-NEXT: %[[mask4:.*]] = and i56 undef, -1099511627776 -; CHECK-NEXT: %[[insert4:.*]] = or i56 %[[mask4]], %[[ext4]] +; CHECK-NEXT: %[[ext3:.*]] = zext i40 1 to i56 +; CHECK-NEXT: %[[mask3:.*]] = and i56 undef, -1099511627776 +; CHECK-NEXT: %[[insert3:.*]] = or i56 %[[mask3]], %[[ext3]] ; CHECK-NOT: store ; CHECK-NOT: load @@ -119,12 +104,11 @@ entry: %ai = load i56, i56* %aiptr %ret = zext i56 %ai to i64 ret i64 %ret -; Here, i16 1 is for %a[0] to %a[1] -; CHECK-NEXT: %[[ext5:.*]] = zext i16 1 to i56 -; CHECK-NEXT: %[[shift5:.*]] = shl i56 %[[ext5]], 40 -; CHECK-NEXT: %[[mask5:.*]] = and i56 %[[insert4]], 1099511627775 -; CHECK-NEXT: %[[insert5:.*]] = or i56 %[[mask5]], %[[shift5]] -; CHECK-NEXT: %[[ret:.*]] = zext i56 %[[insert5]] to i64 +; CHECK-NEXT: %[[ext4:.*]] = zext i16 1 to i56 +; CHECK-NEXT: %[[shift4:.*]] = shl i56 %[[ext4]], 40 +; CHECK-NEXT: %[[mask4:.*]] = and i56 %[[insert3]], 1099511627775 +; CHECK-NEXT: %[[insert4:.*]] = or i56 %[[mask4]], %[[shift4]] +; CHECK-NEXT: %[[ret:.*]] = zext i56 %[[insert4]] to i64 ; CHECK-NEXT: ret i64 %[[ret]] } -- 2.11.0