[dfsan] Fix Len argument type in call to __dfsan_mem_transfer_callback

[EliaGeretto]

Summary

This patch is supposed to solve: https://bugs.llvm.org/show_bug.cgi?id=50075

The function __dfsan_mem_transfer_callback takes a Len argument of type i64; however, when processing a MemTransferInst such as llvm.memcpy.p0i8.p0i8.i32, the len argument has type i32. In order to make the type of len compatible with the one of the callback argument, this change zero-extends it when necessary.

[EliaGeretto]

The CI failure is unrelated to this change; however, I cannot restart the build myself it seems.

[stephan.yichao.zhao]

Thank you for fixing this.

[EliaGeretto]

@stephan.yichao.zhao No problem. However, I do not have push access, could you please push this on my behalf? Thank you.

[stephan.yichao.zhao]

In D101048#2709451, @EliaGeretto wrote:

@stephan.yichao.zhao No problem. However, I do not have push access, could you please push this on my behalf? Thank you.

Sure. will be doing it today.

[EliaGeretto]

@stephan.yichao.zhao Thank you for pushing this. I have a question, though. The commit shows the following line:

From: Elia Geretto <EliaGeretto>

That, however, should have been:

From: Elia Geretto <[e-mail]>

I am now wondering if my account on Differential has some issue, do you know the reason for this? Did I do something wrong submitting the patch?

[stephan.yichao.zhao]

I am now wondering if my account on Differential has some issue, do you know the reason for this? Did I do something wrong submitting the patch?

It turned out that in my submit I used "author" as Elia Geretto <EliaGeretto>, while it should have been Elia Geretto <[e-mail]>.
With this issue, only review.llvm.org knows you are the author because of EliaGeretto, while github does not...
Sorry about this.

[EliaGeretto]

It is fine, no problem. I just wanted to make sure that the configuration etc. on my side was correct.

llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp

if (ClPreserveAlignment) {
     MTI->setDestAlignment(I.getDestAlign() * DFSF.DFS.ShadowWidthBytes);
     MTI->setSourceAlignment(I.getSourceAlign() * DFSF.DFS.ShadowWidthBytes);
   } else {
     MTI->setDestAlignment(Align(DFSF.DFS.ShadowWidthBytes));
     MTI->setSourceAlignment(Align(DFSF.DFS.ShadowWidthBytes));
   }
   if (ClEventCallbacks) {
     IRB.CreateCall(DFSF.DFS.DFSanMemTransferCallbackFn,
-                   {RawDestShadow, I.getLength()});
+                   {RawDestShadow,
+                    IRB.CreateZExtOrTrunc(I.getLength(), DFSF.DFS.IntptrTy)});
   }
 }
 
 void DFSanVisitor::visitReturnInst(ReturnInst &RI) {
   if (!DFSF.IsNativeABI && RI.getReturnValue()) {
     switch (DFSF.IA) {
     case DataFlowSanitizer::IA_TLS: {
       Value *S = DFSF.getShadow(RI.getReturnValue());