[clang] 7dc0734 - [msan] Insert simplification passes after instrumentation

[Vitaly Buka via cfe-commits]

Author: Vitaly Buka
Date: 2022-09-09T00:33:04-07:00
New Revision: 7dc0734567217236a61fa2ed3b3909ac25925ce5

URL: https://github.com/llvm/llvm-project/commit/7dc0734567217236a61fa2ed3b3909ac25925ce5
DIFF: https://github.com/llvm/llvm-project/commit/7dc0734567217236a61fa2ed3b3909ac25925ce5.diff

LOG: [msan] Insert simplification passes after instrumentation

This resolves TODO from D96406.
InstCombine issue is fixed with D133394.

Save 4.5% of .text on CTMark.

Added: 
    

Modified: 
    clang/lib/CodeGen/BackendUtil.cpp

Removed: 
    


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diff  --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 64b21ef608bb1..f4a4f1cd22ab9 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -19,6 +19,7 @@
 #include "llvm/ADT/StringSwitch.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/Analysis/StackSafetyAnalysis.h"
 #include "llvm/Analysis/TargetLibraryInfo.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
@@ -72,14 +73,16 @@
 #include "llvm/Transforms/Instrumentation/InstrProfiling.h"
 #include "llvm/Transforms/Instrumentation/MemProfiler.h"
 #include "llvm/Transforms/Instrumentation/MemorySanitizer.h"
-#include "llvm/Transforms/Instrumentation/SanitizerCoverage.h"
 #include "llvm/Transforms/Instrumentation/SanitizerBinaryMetadata.h"
+#include "llvm/Transforms/Instrumentation/SanitizerCoverage.h"
 #include "llvm/Transforms/Instrumentation/ThreadSanitizer.h"
 #include "llvm/Transforms/ObjCARC.h"
 #include "llvm/Transforms/Scalar.h"
 #include "llvm/Transforms/Scalar/EarlyCSE.h"
 #include "llvm/Transforms/Scalar/GVN.h"
+#include "llvm/Transforms/Scalar/JumpThreading.h"
 #include "llvm/Transforms/Scalar/LowerMatrixIntrinsics.h"
+#include "llvm/Transforms/Scalar/NewGVN.h"
 #include "llvm/Transforms/Utils.h"
 #include "llvm/Transforms/Utils/CanonicalizeAliases.h"
 #include "llvm/Transforms/Utils/Debugify.h"
@@ -97,6 +100,7 @@ using namespace llvm;
 
 namespace llvm {
 extern cl::opt<bool> DebugInfoCorrelate;
+extern cl::opt<bool> RunNewGVN;
 
 // Experiment to move sanitizers earlier.
 static cl::opt<bool> ClSanitizeOnOptimizerEarlyEP(
@@ -661,16 +665,21 @@ static void addSanitizers(const Triple &TargetTriple,
                                        CodeGenOpts.SanitizeMemoryParamRetval);
         MPM.addPass(MemorySanitizerPass(options));
         if (Level != OptimizationLevel::O0) {
-          // MemorySanitizer inserts complex instrumentation that mostly
-          // follows the logic of the original code, but operates on
-          // "shadow" values. It can benefit from re-running some
-          // general purpose optimization passes.
-          MPM.addPass(createModuleToFunctionPassAdaptor(EarlyCSEPass()));
-          // TODO: Consider add more passes like in
-          // addGeneralOptsForMemorySanitizer. EarlyCSEPass makes visible
-          // 
diff erence on size. It's not clear if the rest is still
-          // usefull. InstCombinePass breakes
-          // compiler-rt/test/msan/select_origin.cpp.
+          // MemorySanitizer inserts complex instrumentation that mostly follows
+          // the logic of the original code, but operates on "shadow" values. It
+          // can benefit from re-running some general purpose optimization
+          // passes.
+          MPM.addPass(RecomputeGlobalsAAPass());
+          FunctionPassManager FPM;
+          FPM.addPass(EarlyCSEPass(true /* Enable mem-ssa. */));
+          FPM.addPass(InstCombinePass());
+          FPM.addPass(JumpThreadingPass());
+          if (RunNewGVN)
+            FPM.addPass(NewGVNPass());
+          else
+            FPM.addPass(GVNPass());
+          FPM.addPass(InstCombinePass());
+          MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
         }
       }
     };