[PATCH] D110406: Fix incorrect GEP bitwidth in areNonOverlapSameBaseLoadAndStore()

[Alexander Richardson via Phabricator via llvm-commits]

arichardson created this revision.
arichardson added reviewers: yamauchi, xbolva00, davidxl.
Herald added subscribers: jrtc27, luismarques, s.egerton, PkmX, simoncook, hiraditya, krytarowski, emaste.
arichardson requested review of this revision.
Herald added a project: LLVM.
Herald added a subscriber: llvm-commits.

When using a datalayout that has pointer index width != pointer size this
code triggers an assertion in Value::stripAndAccumulateConstantOffsets().
I encountered this this while compiling FreeBSD for CHERI-RISC-V.
Also update LoadsTest.cpp to use a DataLayout with index width != pointer
width to ensure this case is tested.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D110406

Files:
  llvm/lib/Analysis/Loads.cpp
  llvm/unittests/Analysis/LoadsTest.cpp


Index: llvm/unittests/Analysis/LoadsTest.cpp
===================================================================
--- llvm/unittests/Analysis/LoadsTest.cpp
+++ llvm/unittests/Analysis/LoadsTest.cpp
@@ -28,6 +28,7 @@
   LLVMContext C;
   std::unique_ptr<Module> M = parseIR(C,
                                       R"IR(
+target datalayout = "p:64:64:64:32"
 %class = type <{ i32, i32 }>
 
 define i32 @f() {
Index: llvm/lib/Analysis/Loads.cpp
===================================================================
--- llvm/lib/Analysis/Loads.cpp
+++ llvm/lib/Analysis/Loads.cpp
@@ -451,8 +451,8 @@
                                               const Value *StorePtr,
                                               Type *StoreTy,
                                               const DataLayout &DL) {
-  APInt LoadOffset(DL.getTypeSizeInBits(LoadPtr->getType()), 0);
-  APInt StoreOffset(DL.getTypeSizeInBits(StorePtr->getType()), 0);
+  APInt LoadOffset(DL.getIndexTypeSizeInBits(LoadPtr->getType()), 0);
+  APInt StoreOffset(DL.getIndexTypeSizeInBits(StorePtr->getType()), 0);
   const Value *LoadBase = LoadPtr->stripAndAccumulateConstantOffsets(
       DL, LoadOffset, /* AllowNonInbounds */ false);
   const Value *StoreBase = StorePtr->stripAndAccumulateConstantOffsets(


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D110406.374802.patch
Type: text/x-patch
Size: 1274 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20210924/a4ede3e8/attachment.bin>