GlobalOpt: Drop code to handle typed pointers

[arsenm]

Summary

Fixes assert with pointers with different address spaces. We
could keep looking through addrspacecast, but it would require
checking for null handling of the access address space.

Fixes #62384

[nikic]

llvm/test/Transforms/GlobalOpt/issue62384.ll

3

Why does this need ipsccp and called-value-propagation?

[arsenm]

llvm/test/Transforms/GlobalOpt/issue62384.ll

3

Not really sure but this was as small as I could get the opt pipeline

[aeubanks]

llvm/test/Transforms/GlobalOpt/issue62384.ll

3

you should be able to dump the IR right before globalopt with something like -print-before-all

[arsenm]

llvm/test/Transforms/GlobalOpt/issue62384.ll

3

Of course that's what I first did, but it still did not reproduce with just globalopt at that point. The constantexpr cast moved into init0 after IPSCCP

[nikic]

llvm/test/Transforms/GlobalOpt/issue62384.ll

3

This may be related to either use list order, or to dangling constant expressions.

[arsenm]

Reproduces without other passes now for some reason

[fhahn]

LGTM, thanks!

[arsenm]

b52db60cbbb2b258acb4aad056aba7ad3ca572fa

llvm/lib/Transforms/IPO/GlobalOpt.cpp

optimizeOnceStoredGlobal(GlobalVariable *GV, Value *StoredOnceVal,
   // value was null.
   if (GV->getInitializer()->getType()->isPointerTy() &&
       GV->getInitializer()->isNullValue() &&
       StoredOnceVal->getType()->isPointerTy() &&
       !NullPointerIsDefined(
           nullptr /* F */,
           GV->getInitializer()->getType()->getPointerAddressSpace())) {
     if (Constant *SOVC = dyn_cast<Constant>(StoredOnceVal)) {
-      if (GV->getInitializer()->getType() != SOVC->getType())
-        SOVC = ConstantExpr::getBitCast(SOVC, GV->getInitializer()->getType());
-
       // Optimize away any trapping uses of the loaded value.
       if (OptimizeAwayTrappingUsesOfLoads(GV, SOVC, DL, GetTLI))
         return true;
     } else if (isAllocationFn(StoredOnceVal, GetTLI)) {
       if (auto *CI = dyn_cast<CallInst>(StoredOnceVal)) {
         auto *TLI = &GetTLI(*CI->getFunction());
         if (tryToOptimizeStoreOfAllocationToGlobal(GV, CI, DL, TLI))
           return true;

llvm/test/Transforms/GlobalOpt/issue62384.ll

+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 2
+; RUN: opt -S -p=globalopt %s | FileCheck %s
+
+
[e-mail] = appending global [1 x ptr] [ptr @ctor]
+@gv0 = internal addrspace(1) global ptr null
+@gv1 = internal addrspace(1) global ptr addrspace(3) null
+@gv2 = internal addrspace(1) global ptr addrspace(1) null
+@gv3 = internal addrspace(1) global ptr addrspace(1) null
+
+define internal void @ctor() {
+; CHECK-LABEL: define internal void @ctor() {
+; CHECK-NEXT:    tail call fastcc void @init0(ptr addrspacecast (ptr addrspace(1) null to ptr))
+; CHECK-NEXT:    tail call fastcc void @init1(ptr addrspacecast (ptr addrspace(3) null to ptr))
+; CHECK-NEXT:    tail call fastcc void @init2(ptr addrspace(1) addrspacecast (ptr null to ptr addrspace(1)))
+; CHECK-NEXT:    tail call fastcc void @init3(ptr addrspace(1) addrspacecast (ptr addrspace(2) null to ptr addrspace(1)))
+; CHECK-NEXT:    ret void
+;
+  tail call void @init0(ptr addrspacecast (ptr addrspace(1) null to ptr))
+  tail call void @init1(ptr addrspacecast (ptr addrspace(3) null to ptr))
+  tail call void @init2(ptr addrspace(1) addrspacecast (ptr null to ptr addrspace(1)))
+  tail call void @init3(ptr addrspace(1) addrspacecast (ptr addrspace(2) null to ptr addrspace(1)))
+  ret void
+}
+
+define internal void @init0(ptr %T) {
+; CHECK-LABEL: define internal fastcc void @init0
+; CHECK-SAME: (ptr [[T:%.*]]) unnamed_addr {
+; CHECK-NEXT:    [[LD:%.*]] = load ptr, ptr addrspace(1) @gv0, align 8
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr [[LD]], null
+; CHECK-NEXT:    store ptr addrspacecast (ptr addrspace(1) null to ptr), ptr addrspace(1) @gv0, align 8
+; CHECK-NEXT:    ret void
+;
+  %ld = load ptr, ptr addrspace(1) @gv0, align 8
+  %cmp = icmp eq ptr %ld, null
+  store ptr addrspacecast (ptr addrspace(1) null to ptr), ptr addrspace(1) @gv0, align 8
+  ret void
+}
+
+define internal void @init1(ptr %T) {
+; CHECK-LABEL: define internal fastcc void @init1
+; CHECK-SAME: (ptr [[T:%.*]]) unnamed_addr {
+; CHECK-NEXT:    [[LD:%.*]] = load ptr addrspace(3), ptr addrspace(1) @gv1, align 4
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr addrspace(3) [[LD]], null
+; CHECK-NEXT:    store ptr addrspacecast (ptr addrspace(3) null to ptr), ptr addrspace(1) @gv1, align 8
+; CHECK-NEXT:    ret void
+;
+  %ld = load ptr addrspace(3), ptr addrspace(1) @gv1, align 4
+  %cmp = icmp eq ptr addrspace(3) %ld, null
+  store ptr addrspacecast (ptr addrspace(3) null to ptr), ptr addrspace(1) @gv1, align 8
+  ret void
+}
+
+define internal void @init2(ptr addrspace(1) %T) {
+; CHECK-LABEL: define internal fastcc void @init2
+; CHECK-SAME: (ptr addrspace(1) [[T:%.*]]) unnamed_addr {
+; CHECK-NEXT:    [[LD:%.*]] = load ptr addrspace(1), ptr addrspace(1) @gv2, align 4
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr addrspace(1) [[LD]], null
+; CHECK-NEXT:    store ptr addrspace(1) addrspacecast (ptr null to ptr addrspace(1)), ptr addrspace(1) @gv2, align 8
+; CHECK-NEXT:    ret void
+;
+  %ld = load ptr addrspace(1), ptr addrspace(1) @gv2, align 4
+  %cmp = icmp eq ptr addrspace(1) %ld, null
+  store ptr addrspace(1) addrspacecast (ptr null to ptr addrspace(1)), ptr addrspace(1) @gv2, align 8
+  ret void
+}
+
+define internal void @init3(ptr addrspace(1) %T) {
+; CHECK-LABEL: define internal fastcc void @init3
+; CHECK-SAME: (ptr addrspace(1) [[T:%.*]]) unnamed_addr {
+; CHECK-NEXT:    [[LD:%.*]] = load ptr addrspace(1), ptr addrspace(1) @gv3, align 4
+; CHECK-NEXT:    [[CMP:%.*]] = icmp eq ptr addrspace(1) [[LD]], null
+; CHECK-NEXT:    store ptr addrspace(1) addrspacecast (ptr addrspace(2) null to ptr addrspace(1)), ptr addrspace(1) @gv3, align 8
+; CHECK-NEXT:    ret void
+;
+  %ld = load ptr addrspace(1), ptr addrspace(1) @gv3, align 4
+  %cmp = icmp eq ptr addrspace(1) %ld, null
+  store ptr addrspace(1) addrspacecast (ptr addrspace(2) null to ptr addrspace(1)), ptr addrspace(1) @gv3, align 8
+  ret void
+}