commit 3a6c50f4e03c320ae51eecf2179d037a721a47eb
author Daniel Neilson <dneilson@azul.com> Tue May 29 19:23:50 2018 +0000
committer Daniel Neilson <dneilson@azul.com> Tue May 29 19:23:50 2018 +0000
tree 7290fac1bda83b5113c5cbf9a90d3cbe3f331d91
parent 99feb567bfffa1c965221b1648001614d5b0a3f2

[BasicAA] Teach the analysis about atomic memcpy

Summary:
A simple change to derive mod/ref info from the atomic memcpy
intrinsic in the same way as from the regular memcpy intrinsic.

llvm-svn: 333454

llvm/lib/Analysis/BasicAliasAnalysis.cpp

diff --git a/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/llvm/lib/Analysis/BasicAliasAnalysis.cpp
index c7839bc..0167751 100644
--- a/llvm/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/llvm/lib/Analysis/BasicAliasAnalysis.cpp
@@ -888,7 +888,7 @@
   // operands, i.e., source and destination of any given memcpy must no-alias.
   // If Loc must-aliases either one of these two locations, then it necessarily
   // no-aliases the other.
-  if (auto *Inst = dyn_cast<MemCpyInst>(CS.getInstruction())) {
+  if (auto *Inst = dyn_cast<AnyMemCpyInst>(CS.getInstruction())) {
     AliasResult SrcAA, DestAA;
 
     if ((SrcAA = getBestAAResults().alias(MemoryLocation::getForSource(Inst),

llvm/test/Analysis/BasicAA/cs-cs.ll

diff --git a/llvm/test/Analysis/BasicAA/cs-cs.ll b/llvm/test/Analysis/BasicAA/cs-cs.ll
index 314aff8..9889999 100644
--- a/llvm/test/Analysis/BasicAA/cs-cs.ll
+++ b/llvm/test/Analysis/BasicAA/cs-cs.ll
@@ -4,6 +4,7 @@
 
 declare void @llvm.memset.p0i8.i64(i8* nocapture writeonly, i8, i64, i1) #0
 declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture writeonly, i8* nocapture readonly, i64, i1) #0
+declare void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* nocapture writeonly, i8* nocapture readonly, i64, i32) #0
 
 declare void @a_readonly_func(i8*) #1
 declare void @a_writeonly_func(i8*) #2
@@ -24,6 +25,22 @@
 ; CHECK:   Just Mod:   tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i1 false) <->   tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i1 false)
 }
 
+define void @test2_atomic(i8* %P, i8* %Q) #3 {
+  tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1)
+  tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1)
+  ret void
+
+; CHECK-LABEL: Function: test2_atomic:
+
+; CHECK:   MayAlias:     i8* %P, i8* %Q
+; CHECK:   Just Mod:  Ptr: i8* %P     <->  tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1)
+; CHECK:   Just Ref:  Ptr: i8* %Q     <->  tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1)
+; CHECK:   Just Mod:  Ptr: i8* %P     <->  tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1)
+; CHECK:   Just Ref:  Ptr: i8* %Q     <->  tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1)
+; CHECK:   Just Mod:   tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1) <->   tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1)
+; CHECK:   Just Mod:   tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1) <->   tail call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i64(i8* align 1 %P, i8* align 1 %Q, i64 12, i32 1)
+}
+
 define void @test2a(i8* noalias %P, i8* noalias %Q) #3 {
   tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i1 false)
   tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %P, i8* %Q, i64 12, i1 false)