[Attributor] H2S fix.

[sstefan1]

Summary

Fixing issues that were noticed in D71521

[lebedev.ri]

LG, thank you.

llvm/test/Transforms/Attributor/heap_to_stack.ll

314

Precommit the tests?
https://godbolt.org/z/MG49m9

[sstefan1]

llvm/test/Transforms/Attributor/heap_to_stack.ll

314

Just to make sure, you are suggesting to commit tests only first?

What is the difference, other than build bot failures?

[lebedev.ri]

llvm/test/Transforms/Attributor/heap_to_stack.ll

314

I'm not sure why would there be failures, that test does not trigger any assertions for me locally?
(Obviously, checklines should be changed before commit)

[sstefan1]

llvm/test/Transforms/Attributor/heap_to_stack.ll

314

Ok, I'll commit tests with modified check lines first. Unfortunately I'll have to do that tomorrow.

llvm/lib/Transforms/IPO/Attributor.cpp

auto MallocCallocCheck = [&](Instruction &I) {
     bool IsCalloc = !IsMalloc && isCallocLikeFn(&I, TLI);
     if (!IsMalloc && !IsCalloc) {
       BadMallocCalls.insert(&I);
       return true;
     }
 
     if (IsMalloc) {
       if (auto *Size = dyn_cast<ConstantInt>(I.getOperand(0)))
-        if (Size->getValue().sle(MaxHeapToStackSize))
+        if (Size->getValue().ule(MaxHeapToStackSize))
           if (UsesCheck(I) || FreeCheck(I)) {
             MallocCalls.insert(&I);
             return true;
           }
     } else if (IsCalloc) {
       bool Overflow = false;
       if (auto *Num = dyn_cast<ConstantInt>(I.getOperand(0)))
         if (auto *Size = dyn_cast<ConstantInt>(I.getOperand(1)))
           if ((Size->getValue().umul_ov(Num->getValue(), Overflow))
-                  .sle(MaxHeapToStackSize))
+                  .ule(MaxHeapToStackSize))
             if (!Overflow && (UsesCheck(I) || FreeCheck(I))) {
               MallocCalls.insert(&I);
               return true;
             }
     }
 
     BadMallocCalls.insert(&I);
     return true;

llvm/test/Transforms/Attributor/heap_to_stack.ll

define i32 @test13() {
   %2 = bitcast i8* %1 to i32*
   store i32 10, i32* %2
   %3 = load i32, i32* %2
   tail call void @free(i8* %1)
   ; CHECK: tail call void @free(i8* noalias %1)
   ret i32 %3
 }
 
 define i32 @test_sle() {
   %1 = tail call noalias i8* @malloc(i64 -1)
-  ; FIXME: This should not be transformed
-  ; CHECK: %1 = alloca i8, i64 -1
-  ; CHECK-NEXT: @no_sync_func(i8* noalias nocapture nofree %1)
+  ; CHECK: %1 = tail call noalias i8* @malloc(i64 -1)
+  ; CHECK-NEXT: @no_sync_func(i8* noalias nofree %1)
   tail call void @no_sync_func(i8* %1)
   %2 = bitcast i8* %1 to i32*
   store i32 10, i32* %2
   %3 = load i32, i32* %2
   tail call void @free(i8* %1)
-  ; CHECK-NOT: tail call void @free(i8* noalias %1)
+  ; CHECK: tail call void @free(i8* noalias %1)
+  ret i32 %3
+}
+
+define i32 @test_overflow() {
+  %1 = tail call noalias i8* @calloc(i64 65537, i64 65537)
+  ; CHECK: %1 = tail call noalias i8* @calloc(i64 65537, i64 65537)
+  ; CHECK-NEXT: @no_sync_func(i8* noalias nofree %1)
+  tail call void @no_sync_func(i8* %1)
+  %2 = bitcast i8* %1 to i32*
+  store i32 10, i32* %2
+  %3 = load i32, i32* %2
+  tail call void @free(i8* %1)
+  ; CHECK: tail call void @free(i8* noalias %1)
   ret i32 %3
 }
 
 define void @test14() {
   %1 = tail call noalias i8* @calloc(i64 64, i64 4)
   ; CHECK: %1 = tail call noalias i8* @calloc(i64 64, i64 4)
   ; CHECK-NEXT: @no_sync_func(i8* noalias nofree %1)
   tail call void @no_sync_func(i8* %1)