svn commit: r362341 - head/contrib/llvm-project/llvm/lib/Analysis

[Dimitry Andric]

Author: dim
Date: Thu Jun 18 20:41:43 2020
New Revision: 362341
URL: https://svnweb.freebsd.org/changeset/base/362341

Log:
  Merge commit 0cecafd647cc from llvm git (by Alina Sbirlea):
  
    [BasicAA] Make BasicAA a cfg pass.
  
    Summary:
    Part of the changes in D44564 made BasicAA not CFG only due to it
    using PhiAnalysisValues which may have values invalidated. Subsequent
    patches (rL340613) appear to have addressed this limitation.
  
    BasicAA should not be invalidated by non-CFG-altering passes. A
    concrete example is MemCpyOpt which preserves CFG, but we are testing
    it invalidates BasicAA.
  
    llvm-dev RFC:
    https://groups.google.com/forum/#!topic/llvm-dev/eSPXuWnNfzM
  
    Reviewers: john.brawn, sebpop, hfinkel, brzycki
  
    Subscribers: hiraditya, llvm-commits
  
    Tags: #llvm
  
    Differential Revision: https://reviews.llvm.org/D74353
  
  This fixes an issue with clang's -fintegrated-cc1 feature, which could
  make it output slightly different assembly code, depending on the way it
  was invoked.
  
  In r361755 we attempted to work around it by disabling the integrated
  cc1 stage, but it did not solve the root cause for all situations.
  
  Extensive testing and bisecting showed that the above change finally
  makes the output deterministic, even if -fintegrated-cc1 is on.
  
  Reported by:	Fabian Keil <fk at fabiankeil.de>
  PR:		246630
  MFC after:	3 days

Modified:
  head/contrib/llvm-project/llvm/lib/Analysis/BasicAliasAnalysis.cpp

Modified: head/contrib/llvm-project/llvm/lib/Analysis/BasicAliasAnalysis.cpp
==============================================================================
--- head/contrib/llvm-project/llvm/lib/Analysis/BasicAliasAnalysis.cpp	Thu Jun 18 20:25:42 2020	(r362340)
+++ head/contrib/llvm-project/llvm/lib/Analysis/BasicAliasAnalysis.cpp	Thu Jun 18 20:41:43 2020	(r362341)
@@ -2059,12 +2059,13 @@ char BasicAAWrapperPass::ID = 0;
 void BasicAAWrapperPass::anchor() {}
 
 INITIALIZE_PASS_BEGIN(BasicAAWrapperPass, "basicaa",
-                      "Basic Alias Analysis (stateless AA impl)", false, true)
+                      "Basic Alias Analysis (stateless AA impl)", true, true)
 INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
 INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(PhiValuesWrapperPass)
 INITIALIZE_PASS_END(BasicAAWrapperPass, "basicaa",
-                    "Basic Alias Analysis (stateless AA impl)", false, true)
+                    "Basic Alias Analysis (stateless AA impl)", true, true)
 
 FunctionPass *llvm::createBasicAAWrapperPass() {
   return new BasicAAWrapperPass();