[PATCH] D74083: MemCpyOpt cannot use ABI alignment even if it was not given
Juneyoung Lee via Phabricator via llvm-commits
llvm-commits at lists.llvm.org
Wed Feb 5 12:53:43 PST 2020
aqjune updated this revision to Diff 242732.
aqjune added a comment.
- Let MemsetRanges::addStore explicitly record ABI alignment
Repository:
rG LLVM Github Monorepo
CHANGES SINCE LAST ACTION
https://reviews.llvm.org/D74083/new/
https://reviews.llvm.org/D74083
Files:
llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
llvm/test/Transforms/MemCpyOpt/form-memset.ll
Index: llvm/test/Transforms/MemCpyOpt/form-memset.ll
===================================================================
--- llvm/test/Transforms/MemCpyOpt/form-memset.ll
+++ llvm/test/Transforms/MemCpyOpt/form-memset.ll
@@ -217,7 +217,7 @@
tail call void @llvm.memset.p0i8.i64(i8* %1, i8 0, i64 12, i1 false)
ret void
; CHECK-LABEL: @test6(
-; CHECK: call void @llvm.memset.p0i8.i64(i8* align 4 %2, i8 0, i64 24, i1 false)
+; CHECK: call void @llvm.memset.p0i8.i64(i8* %2, i8 0, i64 24, i1 false)
}
; More aggressive heuristic
@@ -280,7 +280,7 @@
ret void
; CHECK-LABEL: @test10(
; CHECK-NOT: memset
-; CHECK: call void @llvm.memset.p0i8.i64(i8* align 1 %P, i8 0, i64 42, i1 false)
+; CHECK: call void @llvm.memset.p0i8.i64(i8* %P, i8 0, i64 42, i1 false)
; CHECK-NOT: memset
; CHECK: ret void
}
@@ -299,3 +299,16 @@
; CHECK-NOT: store
; CHECK: call void @llvm.memset.p0i8.i64(i8* align 4 %1, i8 1, i64 23, i1 false)
}
+
+; Alignment should be preserved when there is a store with default align
+define void @test12(i32* nocapture %P) nounwind ssp {
+entry:
+ store i32 0, i32* %P
+ %add.ptr = getelementptr inbounds i32, i32* %P, i64 1
+ %0 = bitcast i32* %add.ptr to i8*
+ tail call void @llvm.memset.p0i8.i64(i8* %0, i8 0, i64 11, i1 false)
+ ret void
+; CHECK-LABEL: @test12(
+; CHECK-NOT: store
+; CHECK: call void @llvm.memset.p0i8.i64(i8* align 4 %1, i8 0, i64 15, i1 false)
+}
Index: llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
===================================================================
--- llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
+++ llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
@@ -173,8 +173,10 @@
void addStore(int64_t OffsetFromFirst, StoreInst *SI) {
int64_t StoreSize = DL.getTypeStoreSize(SI->getOperand(0)->getType());
- addRange(OffsetFromFirst, StoreSize,
- SI->getPointerOperand(), SI->getAlignment(), SI);
+ unsigned Align = SI->getAlignment();
+ if (!Align)
+ Align = DL.getABITypeAlignment(SI->getOperand(0)->getType());
+ addRange(OffsetFromFirst, StoreSize, SI->getPointerOperand(), Align, SI);
}
void addMemSet(int64_t OffsetFromFirst, MemSetInst *MSI) {
@@ -387,13 +389,8 @@
// Get the starting pointer of the block.
StartPtr = Range.StartPtr;
- // Determine alignment
- const Align Alignment = DL.getValueOrABITypeAlignment(
- MaybeAlign(Range.Alignment),
- cast<PointerType>(StartPtr->getType())->getElementType());
-
AMemSet = Builder.CreateMemSet(StartPtr, ByteVal, Range.End - Range.Start,
- Alignment);
+ MaybeAlign(Range.Alignment));
LLVM_DEBUG(dbgs() << "Replace stores:\n"; for (Instruction *SI
: Range.TheStores) dbgs()
<< *SI << '\n';
-------------- next part --------------
A non-text attachment was scrubbed...
Name: D74083.242732.patch
Type: text/x-patch
Size: 2878 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20200205/d709f4dd/attachment.bin>
More information about the llvm-commits
mailing list