[llvm] 67f1fe8 - [GlobalOpt] Enable evaluation of atomic stores

[Alexander Shaposhnikov via llvm-commits]

Author: Alexander Shaposhnikov
Date: 2022-07-20T22:33:58Z
New Revision: 67f1fe8597817f9630c84d77ca23852e362e62d6

URL: https://github.com/llvm/llvm-project/commit/67f1fe8597817f9630c84d77ca23852e362e62d6
DIFF: https://github.com/llvm/llvm-project/commit/67f1fe8597817f9630c84d77ca23852e362e62d6.diff

LOG: [GlobalOpt] Enable evaluation of atomic stores

Relax the check to allow evaluation of atomic stores
(but still skip volatile stores).

Test plan:
1/ ninja check-llvm check-clang
2/ Bootstrapped LLVM/Clang pass tests

Differential revision: https://reviews.llvm.org/D129841

Added: 
    

Modified: 
    llvm/lib/Transforms/Utils/Evaluator.cpp
    llvm/test/Transforms/GlobalOpt/ctor-list-opt.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Utils/Evaluator.cpp b/llvm/lib/Transforms/Utils/Evaluator.cpp
index 7b8d8553bac22..3989fbc0da661 100644
--- a/llvm/lib/Transforms/Utils/Evaluator.cpp
+++ b/llvm/lib/Transforms/Utils/Evaluator.cpp
@@ -301,9 +301,9 @@ bool Evaluator::EvaluateBlock(BasicBlock::iterator CurInst, BasicBlock *&NextBB,
     LLVM_DEBUG(dbgs() << "Evaluating Instruction: " << *CurInst << "\n");
 
     if (StoreInst *SI = dyn_cast<StoreInst>(CurInst)) {
-      if (!SI->isSimple()) {
-        LLVM_DEBUG(dbgs() << "Store is not simple! Can not evaluate.\n");
-        return false;  // no volatile/atomic accesses.
+      if (SI->isVolatile()) {
+        LLVM_DEBUG(dbgs() << "Store is volatile! Can not evaluate.\n");
+        return false;  // no volatile accesses.
       }
       Constant *Ptr = getVal(SI->getOperand(1));
       Constant *FoldedPtr = ConstantFoldConstant(Ptr, DL, TLI);

diff  --git a/llvm/test/Transforms/GlobalOpt/ctor-list-opt.ll b/llvm/test/Transforms/GlobalOpt/ctor-list-opt.ll
index d0399416c434f..d351be182cebb 100644
--- a/llvm/test/Transforms/GlobalOpt/ctor-list-opt.ll
+++ b/llvm/test/Transforms/GlobalOpt/ctor-list-opt.ll
@@ -27,6 +27,7 @@
 @Z = global i32 123		; <i32*> [#uses=1]
 @D = global double 0.000000e+00		; <double*> [#uses=1]
 @CTORGV = internal global i1 false		; <i1*> [#uses=2]
+ at GA = global i32 0		; <i32*> [#uses=1]
 
 define internal void @CTOR1() {
 	ret void
@@ -130,3 +131,9 @@ define internal void @CTOR11() {
 define internal void @CTOR12() {
 	ret void
 }
+
+; CHECK-NOT: CTOR13
+define internal void @CTOR13() {
+  store atomic i32 123, i32* @GA seq_cst, align 4
+  ret void
+}