[llvm] [memcpyopt] fix incorrect handling of lifetime markers (PR #143782)

[via llvm-commits]

github-actions[bot] wrote:

<!--LLVM CODE FORMAT COMMENT: {clang-format}-->


:warning: C/C++ code formatter, clang-format found issues in your code. :warning:

<details>
<summary>
You can test this locally with the following command:
</summary>

``````````bash
git-clang-format --diff HEAD~1 HEAD --extensions cpp -- llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
``````````

</details>

<details>
<summary>
View the diff from clang-format here.
</summary>

``````````diff
diff --git a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
index fc439be40..877600034 100644
--- a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
+++ b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
@@ -1367,8 +1367,9 @@ bool MemCpyOptPass::processMemSetMemCpyDependence(MemCpyInst *MemCpy,
 /// Determine whether the pointer V had only undefined content (due to Def) up
 /// to the given Size, either because it was freshly alloca'd or started its
 /// lifetime by walking the MSSA graph.
-static bool hadUndefContentsBefore(MemorySSA *MSSA, BatchAAResults &BAA, Value *V,
-                                   MemoryAccess *Clobber, MemoryLocation Loc, Value *Size) {
+static bool hadUndefContentsBefore(MemorySSA *MSSA, BatchAAResults &BAA,
+                                   Value *V, MemoryAccess *Clobber,
+                                   MemoryLocation Loc, Value *Size) {
   while (1) {
     Clobber = MSSA->getWalker()->getClobberingMemoryAccess(Clobber, Loc, BAA);
     MemoryDef *Def = dyn_cast<MemoryDef>(Clobber);
@@ -1416,14 +1417,16 @@ static bool hadUndefContentsBefore(MemorySSA *MSSA, BatchAAResults &BAA, Value *
 // If the memcpy is larger than the previous, but the memory was undef prior to
 // that, we can just ignore the tail. Technically we're only interested in the
 // bytes from 0..MemSrcOffset and MemSrcLength+MemSrcOffset..CopySize here, but
-// as we can't easily represent this location (hadUndefContentsBefore uses mustAlias
-// which cannot deal with offsets), we use the full 0..CopySize range.
+// as we can't easily represent this location (hadUndefContentsBefore uses
+// mustAlias which cannot deal with offsets), we use the full 0..CopySize range.
 static bool overreadUndefContents(MemorySSA *MSSA, MemCpyInst *MemCpy,
                                   MemIntrinsic *MemSrc, BatchAAResults &BAA) {
   Value *CopySize = MemCpy->getLength();
   MemoryLocation LoadLoc = MemoryLocation::getForSource(MemCpy);
-  MemoryAccess *MemSrcAccess = MSSA->getMemoryAccess(MemSrc)->getDefiningAccess();
-  if (hadUndefContentsBefore(MSSA, BAA, MemCpy->getSource(), MemSrcAccess, LoadLoc, CopySize))
+  MemoryAccess *MemSrcAccess =
+      MSSA->getMemoryAccess(MemSrc)->getDefiningAccess();
+  if (hadUndefContentsBefore(MSSA, BAA, MemCpy->getSource(), MemSrcAccess,
+                             LoadLoc, CopySize))
     return true;
   return false;
 }
@@ -1791,8 +1794,8 @@ bool MemCpyOptPass::processMemCpy(MemCpyInst *M, BasicBlock::iterator &BBI) {
           return true;
 
   MemoryLocation SrcLoc = MemoryLocation::getForSource(M);
-  MemoryAccess *SrcClobber = MSSA->getWalker()->getClobberingMemoryAccess(
-      AnyClobber, SrcLoc, BAA);
+  MemoryAccess *SrcClobber =
+      MSSA->getWalker()->getClobberingMemoryAccess(AnyClobber, SrcLoc, BAA);
 
   // There are five possible optimizations we can do for memcpy:
   //   a) memcpy-memcpy xform which exposes redundance for DSE.
@@ -1832,7 +1835,8 @@ bool MemCpyOptPass::processMemCpy(MemCpyInst *M, BasicBlock::iterator &BBI) {
       }
     }
 
-    if (hadUndefContentsBefore(MSSA, BAA, M->getSource(), AnyClobber, SrcLoc, M->getLength())) {
+    if (hadUndefContentsBefore(MSSA, BAA, M->getSource(), AnyClobber, SrcLoc,
+                               M->getLength())) {
       LLVM_DEBUG(dbgs() << "Removed memcpy from undef\n");
       eraseInstruction(M);
       ++NumMemCpyInstr;

``````````

</details>


https://github.com/llvm/llvm-project/pull/143782