[AMDGPU] Fix assertion due to initializer list

Sometimes a global var is replaced by a different llvm value. clang use GetAddrOfGlobalVar to get the original llvm global variable.
For most targets, GetAddrOfGlobalVar returns either the llvm global variable or a bitcast of the llvm global variable.
However, for AMDGPU target, GetAddrOfGlobalVar returns the addrspace cast or addrspace cast plus bitcast of the llvm global variable.
To get the llvm global variable, these casts need to be stripped, otherwise there is assertion.

This patch fixes that.

Differential Revision: https://reviews.llvm.org/D69129

llvm-svn: 375362

1 files changed, 6 insertions, 10 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 8eb2176ca3a..b05a58848e8 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -3546,7 +3546,8 @@ CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName,
               // Make a new global with the correct type, this is now guaranteed
               // to work.
               auto *NewGV = cast<llvm::GlobalVariable>(
-                  GetAddrOfGlobalVar(D, InitType, IsForDefinition));
+                  GetAddrOfGlobalVar(D, InitType, IsForDefinition)
+                      ->stripPointerCasts());
 
               // Erase the old global, since it is no longer used.
               GV->eraseFromParent();
@@ -3928,14 +3929,8 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
   llvm::Constant *Entry =
       GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative));
 
-  // Strip off a bitcast if we got one back.
-  if (auto *CE = dyn_cast<llvm::ConstantExpr>(Entry)) {
-    assert(CE->getOpcode() == llvm::Instruction::BitCast ||
-           CE->getOpcode() == llvm::Instruction::AddrSpaceCast ||
-           // All zero index gep.
-           CE->getOpcode() == llvm::Instruction::GetElementPtr);
-    Entry = CE->getOperand(0);
-  }
+  // Strip off pointer casts if we got them.
+  Entry = Entry->stripPointerCasts();
 
   // Entry is now either a Function or GlobalVariable.
   auto *GV = dyn_cast<llvm::GlobalVariable>(Entry);
@@ -3958,7 +3953,8 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
 
     // Make a new global with the correct type, this is now guaranteed to work.
     GV = cast<llvm::GlobalVariable>(
-        GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)));
+        GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative))
+            ->stripPointerCasts());
 
     // Replace all uses of the old global with the new global
     llvm::Constant *NewPtrForOldDecl =