[llvm] 8a0cd23 - Revert "[MemDep][NFCI] Remove redundant dyn_cast, replace with cast"

[Philip Reames via llvm-commits]

Author: Philip Reames
Date: 2022-06-07T13:21:31-07:00
New Revision: 8a0cd23326050a7b999efa2cf455880772ce9211

URL: https://github.com/llvm/llvm-project/commit/8a0cd23326050a7b999efa2cf455880772ce9211
DIFF: https://github.com/llvm/llvm-project/commit/8a0cd23326050a7b999efa2cf455880772ce9211.diff

LOG: Revert "[MemDep][NFCI] Remove redundant dyn_cast, replace with cast"

This reverts commit 180d3f251d1ad5473705d3f00e6d426b5f8162e6.  This commit is simply wrong.  IsLoad is set within the same file based on modref state, not whether the instruction is a LoadInst.

This went uncaught because cast<Ty>(X) has been broken.  See https://discourse.llvm.org/t/cast-x-is-broken-implications-and-proposal-to-address/63033 for context.

Added: 
    

Modified: 
    llvm/lib/Analysis/MemoryDependenceAnalysis.cpp

Removed: 
    


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diff  --git a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
index a3a9f437a93a..78383d5c1af1 100644
--- a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -402,8 +402,8 @@ MemDepResult MemoryDependenceResults::getSimplePointerDependencyFrom(
   // forwarding, but any mayalias write can be assumed to be noalias.
   // Arguably, this logic should be pushed inside AliasAnalysis itself.
   if (isLoad && QueryInst) {
-    LoadInst *LI = cast<LoadInst>(QueryInst);
-    if (LI->hasMetadata(LLVMContext::MD_invariant_load))
+    LoadInst *LI = dyn_cast<LoadInst>(QueryInst);
+    if (LI && LI->hasMetadata(LLVMContext::MD_invariant_load))
       isInvariantLoad = true;
   }