SimpleGVN: do corresponding unsafe cast to jlvaluet (#2840)

Author: wsmoses

enzyme/Enzyme/SimpleGVN.cpp

@@ -186,17 +186,13 @@ Value *extractValue(IRBuilder<> &Builder, Value *StoredVal, Type *LoadType,
   if (LoadIntTy != LoadType) {
     if (LoadType->isPointerTy()) {
       if (cast<PointerType>(LoadType)->getAddressSpace() == 10) {
-        if (CustomErrorHandler) {
-          CustomErrorHandler(
-              "SimpleGVN: attempt to convert integer to GC pointer",
-              wrap(StoredVal), ErrorType::ShowInternalError, nullptr, nullptr,
-              wrap(&Builder));
-          return nullptr;
-        }
-        llvm::report_fatal_error(
-            "SimpleGVN: attempt to convert integer to GC pointer");
+        Type *EmptyStructTy = StructType::get(LoadType->getContext());
+        Type *PtrAddrSpace0 = PointerType::get(EmptyStructTy, 0);
+        Value *Ptr0 = Builder.CreateIntToPtr(StoredVal, PtrAddrSpace0);
+        StoredVal = Builder.CreateAddrSpaceCast(Ptr0, LoadType);
+      } else {
+        StoredVal = Builder.CreateIntToPtr(StoredVal, LoadType);
       }
-      StoredVal = Builder.CreateIntToPtr(StoredVal, LoadType);
     } else {
       if (!CastInst::castIsValid(Instruction::BitCast, StoredVal->getType(),
                                  LoadType)) {

enzyme/test/Enzyme/SimpleGVN/int_to_gc_ptr.ll

@@ -0,0 +1,20 @@
+; RUN: %opt < %s %newLoadEnzyme -passes="simple-gvn" -S | FileCheck %s
+
+target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128-ni:10:11:12:13"
+
+define {} addrspace(10)* @test_int_to_gc_ptr(i64* noalias %ptr, i64 %val) {
+entry:
+  store i64 %val, i64* %ptr
+  %c = bitcast i64* %ptr to {} addrspace(10)**
+  %loaded = load {} addrspace(10)*, {} addrspace(10)** %c
+  ret {} addrspace(10)* %loaded
+}
+
+; CHECK: define {} addrspace(10)* @test_int_to_gc_ptr(i64* noalias %ptr, i64 %val) {
+; CHECK-NEXT: entry:
+; CHECK-NEXT:   store i64 %val, i64* %ptr, align 8
+; CHECK-NEXT:   %c = bitcast i64* %ptr to {} addrspace(10)**
+; CHECK-NEXT:   %[[INTTOPTR:.+]] = inttoptr i64 %val to {}*
+; CHECK-NEXT:   %[[ADDRSPACECAST:.+]] = addrspacecast {}* %[[INTTOPTR]] to {} addrspace(10)*
+; CHECK-NEXT:   ret {} addrspace(10)* %[[ADDRSPACECAST]]
+; CHECK-NEXT: }