[MemoryBuiltins] Avoid comparing against Type::getInt8PtrTy(0)

[arichardson]

Summary

This does not make sense with opaque pointers, and also caused issues for
CHERI/Morello where hardcoding address-space zero prevented optimization.

Downstream change: https://git.morello-project.org/morello/llvm-project/-/merge_requests/180
Co-authored-by: Silviu Baranga <[e-mail]>

[lebedev.ri]

LG

llvm/lib/Analysis/MemoryBuiltins.cpp

getAllocationDataForFunction(const Function *Callee, AllocType AllocTy,
   if ((FnData->AllocTy & AllocTy) != FnData->AllocTy)
     return std::nullopt;
 
   // Check function prototype.
   int FstParam = FnData->FstParam;
   int SndParam = FnData->SndParam;
   FunctionType *FTy = Callee->getFunctionType();
 
-  if (FTy->getReturnType() == Type::getInt8PtrTy(FTy->getContext()) &&
+  if (FTy->getReturnType()->isPointerTy() &&
       FTy->getNumParams() == FnData->NumParams &&
       (FstParam < 0 ||
        (FTy->getParamType(FstParam)->isIntegerTy(32) ||
         FTy->getParamType(FstParam)->isIntegerTy(64))) &&
       (SndParam < 0 ||
        FTy->getParamType(SndParam)->isIntegerTy(32) ||
        FTy->getParamType(SndParam)->isIntegerTy(64)))
     return *FnData;
bool llvm::isLibFreeFunction(const Function *F, const LibFunc TLIFn) {
   // Check free prototype.
   // FIXME: workaround for PR5130, this will be obsolete when a nobuiltin
   // attribute will exist.
   FunctionType *FTy = F->getFunctionType();
   if (!FTy->getReturnType()->isVoidTy())
     return false;
   if (FTy->getNumParams() != FnData->NumParams)
     return false;
-  if (FTy->getParamType(0) != Type::getInt8PtrTy(F->getContext()))
+  if (!FTy->getParamType(0)->isPointerTy())
     return false;
 
   return true;
 }
 
 Value *llvm::getFreedOperand(const CallBase *CB, const TargetLibraryInfo *TLI) {
   bool IsNoBuiltinCall;
   const Function *Callee = getCalledFunction(CB, IsNoBuiltinCall);

llvm/test/Transforms/InstCombine/malloc-free-addrspace.ll

+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --function-signature
+; RUN: opt -passes=instcombine -S < %s  | FileCheck %s
+
+target datalayout = "e-m:e-p200:128:128:128:64-A200-P200-G200"
+
+define i64 @remove_malloc() addrspace(200) {
+; CHECK-LABEL: define {{[^@]+}}@remove_malloc() addrspace(200) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    ret i64 0
+;
+entry:
+  %call = call align 16 ptr addrspace(200) @malloc(i64 4)
+  call void @free(ptr addrspace(200) %call)
+  ret i64 0
+}
+
+define i64 @remove_calloc() addrspace(200) {
+; CHECK-LABEL: define {{[^@]+}}@remove_calloc() addrspace(200) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    ret i64 0
+;
+entry:
+  %call = call ptr addrspace(200) @calloc(i64 1, i64 4)
+  call void @free(ptr addrspace(200) %call)
+  ret i64 0
+}
+define i64 @remove_aligned_alloc() addrspace(200) {
+; CHECK-LABEL: define {{[^@]+}}@remove_aligned_alloc() addrspace(200) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    ret i64 0
+;
+entry:
+  %call = call align 4 ptr addrspace(200) @aligned_alloc(i64 4, i64 4)
+  call void @free(ptr addrspace(200) %call)
+  ret i64 0
+}
+
+define i64 @remove_strdup(ptr addrspace(200) %arg) addrspace(200) {
+; CHECK-LABEL: define {{[^@]+}}@remove_strdup
+; CHECK-SAME: (ptr addrspace(200) [[ARG:%.*]]) addrspace(200) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    ret i64 0
+;
+entry:
+  %call = call align 4 ptr addrspace(200) @strdup(ptr addrspace(200) %arg)
+  call void @free(ptr addrspace(200) %call)
+  ret i64 0
+}
+
+define i64 @remove_new(ptr addrspace(200) %arg) addrspace(200) {
+; CHECK-LABEL: define {{[^@]+}}@remove_new
+; CHECK-SAME: (ptr addrspace(200) [[ARG:%.*]]) addrspace(200) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    ret i64 0
+;
+entry:
+  %call = call align 4 ptr addrspace(200) @_Znwm(i64 4)
+  call void @_ZdlPv(ptr addrspace(200) %call)
+  ret i64 0
+}
+
+define i64 @remove_new_array(ptr addrspace(200) %arg) addrspace(200) {
+; CHECK-LABEL: define {{[^@]+}}@remove_new_array
+; CHECK-SAME: (ptr addrspace(200) [[ARG:%.*]]) addrspace(200) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    ret i64 0
+;
+entry:
+  %call = call align 4 ptr addrspace(200) @_Znam(i64 4)
+  call void @_ZdaPv(ptr addrspace(200) %call)
+  ret i64 0
+}
+
+declare noalias ptr addrspace(200) @calloc(i64, i64) addrspace(200)  nounwind allockind("alloc,zeroed") allocsize(0,1) "alloc-family"="malloc"
+declare noalias ptr addrspace(200) @malloc(i64) addrspace(200) allockind("alloc,uninitialized") allocsize(0) "alloc-family"="malloc"
+declare noalias ptr addrspace(200) @aligned_alloc(i64, i64) addrspace(200) allockind("alloc,uninitialized,aligned") allocsize(1) "alloc-family"="malloc"
+declare noalias ptr addrspace(200) @strdup(ptr addrspace(200) %arg) addrspace(200)
+declare void @free(ptr addrspace(200)) addrspace(200) allockind("free") "alloc-family"="malloc"
+; new/delete
+declare noalias ptr addrspace(200) @_Znwm(i64) addrspace(200)
+declare void @_ZdlPv(ptr addrspace(200)) addrspace(200)
+; new[]/delete[]
+declare noalias ptr addrspace(200) @_Znam(i64) addrspace(200)
+declare void @_ZdaPv(ptr addrspace(200)) addrspace(200)