Skip anything that is not an instruction from current basic block

Author: e-kud

llvm/lib/CodeGen/CodeGenPrepare.cpp

@@ -6100,11 +6100,11 @@ bool CodeGenPrepare::optimizeMemoryInst(Instruction *MemoryInst, Value *Addr,
 
       if (!ResultIndex) {
         auto PtrInst = dyn_cast<Instruction>(ResultPtr);
-        // Here we know that we have just a pointer without any offsets.  If
-        // this pointer comes from a different from the current basic block we
-        // need to know how to recreate it in another basic block.
-        // Currently we don't support recreation of any of instruction.
-        if (PtrInst && PtrInst->getParent() != MemoryInst->getParent())
+        // We know that we have a pointer without any offsets. If this pointer
+        // originates from a different basic block than the current one, we
+        // must be able to recreate it in the current basic block.
+        // We do not support the recreation of any instructions yet.
+        if (!PtrInst || PtrInst->getParent() != MemoryInst->getParent())
           return Modified;
         SunkAddr = ResultPtr;
       } else {

llvm/test/Transforms/CodeGenPrepare/X86/sink-addr-recreate.ll

@@ -53,8 +53,9 @@ define void @addr_from_arg(ptr %ptr, i1 %p) {
 ; CHECK:       [[BODY_1]]:
 ; CHECK-NEXT:    [[SUNKADDR:%.*]] = bitcast ptr [[PTR]] to ptr
 ; CHECK-NEXT:    store <4 x i32> zeroinitializer, ptr [[SUNKADDR]], align 4
-; CHECK-NEXT:    [[UNUSED:%.*]] = load <4 x i32>, ptr [[PTR]], align 4
-; CHECK-NEXT:    store <4 x i32> zeroinitializer, ptr [[PTR]], align 4
+; CHECK-NEXT:    [[TMP0:%.*]] = bitcast ptr [[PTR]] to ptr
+; CHECK-NEXT:    [[UNUSED:%.*]] = load <4 x i32>, ptr [[TMP0]], align 4
+; CHECK-NEXT:    store <4 x i32> zeroinitializer, ptr [[TMP0]], align 4
 ; CHECK-NEXT:    ret void
 ;
 entry:
@@ -84,8 +85,8 @@ define void @addr_from_global(i1 %p) {
 ; CHECK:       [[BODY_1]]:
 ; CHECK-NEXT:    [[GEP1:%.*]] = bitcast ptr @globalptr to ptr
 ; CHECK-NEXT:    store <4 x i32> zeroinitializer, ptr [[GEP1]], align 4
-; CHECK-NEXT:    [[UNUSED:%.*]] = load <4 x i32>, ptr @globalptr, align 4
-; CHECK-NEXT:    store <4 x i32> zeroinitializer, ptr @globalptr, align 4
+; CHECK-NEXT:    [[UNUSED:%.*]] = load <4 x i32>, ptr [[GEP1]], align 4
+; CHECK-NEXT:    store <4 x i32> zeroinitializer, ptr [[GEP1]], align 4
 ; CHECK-NEXT:    ret void
 ;
 entry: