From 7137eb36e1ca4f5a9730676d860354bb5eab394b Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault@amd.com>
Date: Tue, 15 Jul 2014 00:56:40 +0000
Subject: [PATCH] Teach GetUnderlyingObject / BasicAA about addrspacecast

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213025 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Analysis/BasicAliasAnalysis.cpp           |  3 ++-
 lib/Analysis/ValueTracking.cpp                |  3 ++-
 .../DeadStoreElimination/PartialStore.ll      | 22 ++++++++++++++++---
 .../Transforms/DeadStoreElimination/simple.ll | 17 ++++++++++++++
 4 files changed, 40 insertions(+), 5 deletions(-)

diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index fe90b84533d..241355e9c3c 100644
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -309,7 +309,8 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
       return V;
     }
 
-    if (Op->getOpcode() == Instruction::BitCast) {
+    if (Op->getOpcode() == Instruction::BitCast ||
+        Op->getOpcode() == Instruction::AddrSpaceCast) {
       V = Op->getOperand(0);
       continue;
     }
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index 9e2deaa18e3..bfdc349bf04 100644
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -1901,7 +1901,8 @@ llvm::GetUnderlyingObject(Value *V, const DataLayout *TD, unsigned MaxLookup) {
   for (unsigned Count = 0; MaxLookup == 0 || Count < MaxLookup; ++Count) {
     if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
       V = GEP->getPointerOperand();
-    } else if (Operator::getOpcode(V) == Instruction::BitCast) {
+    } else if (Operator::getOpcode(V) == Instruction::BitCast ||
+               Operator::getOpcode(V) == Instruction::AddrSpaceCast) {
       V = cast<Operator>(V)->getOperand(0);
     } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) {
       if (GA->mayBeOverridden())
diff --git a/test/Transforms/DeadStoreElimination/PartialStore.ll b/test/Transforms/DeadStoreElimination/PartialStore.ll
index 4799ef3383b..80c2bfae846 100644
--- a/test/Transforms/DeadStoreElimination/PartialStore.ll
+++ b/test/Transforms/DeadStoreElimination/PartialStore.ll
@@ -45,9 +45,9 @@ define void @test4(i8* %P) {
 
   store i8 19, i8* %P  ;; dead
   %A = getelementptr i8* %P, i32 3
-  
+
   store i8 42, i8* %A  ;; dead
-  
+
   %Q = bitcast i8* %P to double*
   store double 0.0, double* %Q
   ret void
@@ -61,7 +61,7 @@ define void @test5(i32 %i) nounwind ssp {
   %C = getelementptr i8* %B, i32 %i
   store i8 10, i8* %C        ;; Dead store to variable index.
   store i32 20, i32* %A
-  
+
   call void @test5a(i32* %A)
   ret void
 ; CHECK-LABEL: @test5(
@@ -69,3 +69,19 @@ define void @test5(i32 %i) nounwind ssp {
 ; CHECK-NEXT: store i32 20
 ; CHECK-NEXT: call void @test5a
 }
+
+declare void @test5a_as1(i32*)
+define void @test5_addrspacecast(i32 %i) nounwind ssp {
+  %A = alloca i32
+  %B = addrspacecast i32* %A to i8 addrspace(1)*
+  %C = getelementptr i8 addrspace(1)* %B, i32 %i
+  store i8 10, i8 addrspace(1)* %C        ;; Dead store to variable index.
+  store i32 20, i32* %A
+
+  call void @test5a(i32* %A)
+  ret void
+; CHECK-LABEL: @test5_addrspacecast(
+; CHECK-NEXT: alloca
+; CHECK-NEXT: store i32 20
+; CHECK-NEXT: call void @test5a
+}
diff --git a/test/Transforms/DeadStoreElimination/simple.ll b/test/Transforms/DeadStoreElimination/simple.ll
index cdfe2268eff..1e813852b04 100644
--- a/test/Transforms/DeadStoreElimination/simple.ll
+++ b/test/Transforms/DeadStoreElimination/simple.ll
@@ -172,6 +172,23 @@ define i32* @test13() {
 ; CHECK-NEXT: call void
 }
 
+define i32 addrspace(1)* @test13_addrspacecast() {
+  %p = tail call i8* @malloc(i32 4)
+  %p.bc = bitcast i8* %p to i32*
+  %P = addrspacecast i32* %p.bc to i32 addrspace(1)*
+  %DEAD = load i32 addrspace(1)* %P
+  %DEAD2 = add i32 %DEAD, 1
+  store i32 %DEAD2, i32 addrspace(1)* %P
+  call void @test13f( )
+  store i32 0, i32 addrspace(1)* %P
+  ret i32 addrspace(1)* %P
+; CHECK: @test13_addrspacecast()
+; CHECK-NEXT: malloc
+; CHECK-NEXT: bitcast
+; CHECK-NEXT: addrspacecast
+; CHECK-NEXT: call void
+}
+
 declare noalias i8* @malloc(i32)
 declare noalias i8* @calloc(i32, i32)