Fix evaluator for non-zero alloca addr space

[yaxunl]

Summary

The evaluator goes through BB and creates global vars as temporary values to evaluate
results of LLVM instructions. It creates undef for alloca, however it assumes alloca
in addr space 0. If the next instruction is addrspace cast to 0, then we get an invalid
cast instruction.

This patch let the temp global var have an address space matching alloca addr space,
so that the valuation can be done.

[arsenm]

test/Transforms/GlobalOpt/amdgcn-ctor-alloca.ll

7–8 ↗

(On Diff #147559)

Needs positive checks

[yaxunl]

Add positive check.

[arsenm]

LGTM

llvm/trunk/lib/Transforms/Utils/Evaluator.cpp

while (true) {
     } else if (AllocaInst *AI = dyn_cast<AllocaInst>(CurInst)) {
       if (AI->isArrayAllocation()) {
         LLVM_DEBUG(dbgs() << "Found an array alloca. Can not evaluate.\n");
         return false;  // Cannot handle array allocs.
       }
       Type *Ty = AI->getAllocatedType();
       AllocaTmps.push_back(llvm::make_unique<GlobalVariable>(
           Ty, false, GlobalValue::InternalLinkage, UndefValue::get(Ty),
-          AI->getName()));
+          AI->getName(), /*TLMode=*/GlobalValue::NotThreadLocal,
+          AI->getType()->getPointerAddressSpace()));
       InstResult = AllocaTmps.back().get();
       LLVM_DEBUG(dbgs() << "Found an alloca. Result: " << *InstResult << "\n");
     } else if (isa<CallInst>(CurInst) || isa<InvokeInst>(CurInst)) {
       CallSite CS(&*CurInst);
 
       // Debug info can safely be ignored here.
       if (isa<DbgInfoIntrinsic>(CS.getInstruction())) {
         LLVM_DEBUG(dbgs() << "Ignoring debug info.\n");

llvm/trunk/test/Transforms/GlobalOpt/amdgcn-ctor-alloca.ll

+; RUN: opt -data-layout=A5 -globalopt %s -S -o - | FileCheck %s
+
+; CHECK-NOT: @g
+@g = internal addrspace(1) global i32* zeroinitializer
+
+; CHECK: @llvm.global_ctors = appending global [0 x { i32, void ()*, i8* }] zeroinitializer
[e-mail]_ctors = appending global [1 x { i32, void ()*, i8* }]
+   [{ i32, void ()*, i8* } { i32 65535, void ()* @ctor, i8* null }]
+
+; CHECK-NOT: @ctor
+define internal void @ctor()  {
+  %addr = alloca i32, align 8, addrspace(5)
+  %tmp = addrspacecast i32 addrspace(5)* %addr to i32*
+  store i32* %tmp, i32* addrspace(1)* @g
+  ret void
+}
+