Reapply [ConstantFold] Drop gep of gep fold entirely (#95126)

Reapplying without changes. The flang+openmp buildbot failure
should be addressed by https://github.com/llvm/llvm-project/pull/94541.

-----

This is a followup to https://github.com/llvm/llvm-project/pull/93823
and drops the DataLayout-unaware GEP of GEP fold entirely. All cases are
now left to the DataLayout-aware constant folder, which will fold
everything to a single i8 GEP.

We didn't have any test coverage for this fold in LLVM, but some Clang
tests change.

1 files changed, 2 insertions, 3 deletions

diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
index 8b2aa6b..0089586 100644
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -5068,9 +5068,8 @@ static Value *simplifyGEPInst(Type *SrcTy, Value *Ptr,
     return nullptr;
 
   if (!ConstantExpr::isSupportedGetElementPtr(SrcTy))
-    // TODO(gep_nowrap): Pass on the whole GEPNoWrapFlags.
-    return ConstantFoldGetElementPtr(SrcTy, cast<Constant>(Ptr),
-                                     NW.isInBounds(), std::nullopt, Indices);
+    return ConstantFoldGetElementPtr(SrcTy, cast<Constant>(Ptr), std::nullopt,
+                                     Indices);
 
   auto *CE =
       ConstantExpr::getGetElementPtr(SrcTy, cast<Constant>(Ptr), Indices, NW);