[llvm] 9eb6572 - [LV] Add back CantReorderMemOps remark.

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2022-07-04T17:23:47+01:00
New Revision: 9eb657278611665433d30fb37979d1df48af2ac8

URL: https://github.com/llvm/llvm-project/commit/9eb657278611665433d30fb37979d1df48af2ac8
DIFF: https://github.com/llvm/llvm-project/commit/9eb657278611665433d30fb37979d1df48af2ac8.diff

LOG: [LV] Add back CantReorderMemOps remark.

Add back remark unintentionally dropped by 644a965c1efef68f.

I will add a LV test separately, so we do not have to rely on a Clang
test to catch this.

Added: 
    

Modified: 
    clang/test/Frontend/optimization-remark-options.c
    llvm/lib/Transforms/Vectorize/LoopVectorize.cpp

Removed: 
    


################################################################################
diff  --git a/clang/test/Frontend/optimization-remark-options.c b/clang/test/Frontend/optimization-remark-options.c
index 3509a388d0f6..96e480d140be 100644
--- a/clang/test/Frontend/optimization-remark-options.c
+++ b/clang/test/Frontend/optimization-remark-options.c
@@ -1,5 +1,5 @@
 // REQUIRES: x86-registered-target
-// RUN: %clang -O1 -fvectorize -target x86_64-unknown-unknown -Rpass-analysis=loop-vectorize -emit-llvm -S %s -o - 2>&1 | FileCheck %s
+// RUN: %clang -O1 -fvectorize -target x86_64-unknown-unknown -mllvm -vectorize-memory-check-threshold=8 -Rpass-analysis=loop-vectorize -emit-llvm -S %s -o - 2>&1 | FileCheck %s
 
 // CHECK: {{.*}}:10:11: remark: loop not vectorized: cannot prove it is safe to reorder floating-point operations; allow reordering by specifying '#pragma clang loop vectorize(enable)' before the loop or by providing the compiler option '-ffast-math'.
 

diff  --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index c9e9136bbd3c..b48c3e18def5 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -10514,8 +10514,18 @@ bool LoopVectorizePass::processLoop(Loop *L) {
     bool ForceVectorization =
         Hints.getForce() == LoopVectorizeHints::FK_Enabled;
     if (!ForceVectorization &&
-        !areRuntimeChecksProfitable(Checks, VF, L, *PSE.getSE()))
+        !areRuntimeChecksProfitable(Checks, VF, L, *PSE.getSE())) {
+      ORE->emit([&]() {
+        return OptimizationRemarkAnalysisAliasing(
+                   DEBUG_TYPE, "CantReorderMemOps", L->getStartLoc(),
+                   L->getHeader())
+               << "loop not vectorized: cannot prove it is safe to reorder "
+                  "memory operations";
+      });
+      LLVM_DEBUG(dbgs() << "LV: Too many memory checks needed.\n");
+      Hints.emitRemarkWithHints();
       return false;
+    }
   }
 
   // Identify the diagnostic messages that should be produced.