diff options
Diffstat (limited to 'llvm/lib/Transforms/Utils/LCSSA.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Utils/LCSSA.cpp | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/llvm/lib/Transforms/Utils/LCSSA.cpp b/llvm/lib/Transforms/Utils/LCSSA.cpp index 5d818cc734b..68c6b74d5e5 100644 --- a/llvm/lib/Transforms/Utils/LCSSA.cpp +++ b/llvm/lib/Transforms/Utils/LCSSA.cpp @@ -51,6 +51,15 @@ using namespace llvm; STATISTIC(NumLCSSA, "Number of live out of a loop variables"); +#ifdef EXPENSIVE_CHECKS +static bool VerifyLoopLCSSA = true; +#else +static bool VerifyLoopLCSSA = false; +#endif +static cl::opt<bool,true> +VerifyLoopLCSSAFlag("verify-loop-lcssa", cl::location(VerifyLoopLCSSA), + cl::desc("Verify loop lcssa form (time consuming)")); + /// Return true if the specified block is in the list. static bool isExitBlock(BasicBlock *BB, const SmallVectorImpl<BasicBlock *> &ExitBlocks) { @@ -322,10 +331,17 @@ struct LCSSAWrapperPass : public FunctionPass { bool runOnFunction(Function &F) override; void verifyAnalysis() const override { - assert( - all_of(*LI, - [&](Loop *L) { return L->isRecursivelyLCSSAForm(*DT, *LI); }) && - "LCSSA form is broken!"); + // This check is very expensive. On the loop intensive compiles it may cause + // up to 10x slowdown. Currently it's disabled by default. LPPassManager + // always does limited form of the LCSSA verification. Similar reasoning + // was used for the LoopInfo verifier. + if (VerifyLoopLCSSA) { + assert(all_of(*LI, + [&](Loop *L) { + return L->isRecursivelyLCSSAForm(*DT, *LI); + }) && + "LCSSA form is broken!"); + } }; /// This transformation requires natural loop information & requires that @@ -342,6 +358,10 @@ struct LCSSAWrapperPass : public FunctionPass { AU.addPreserved<GlobalsAAWrapperPass>(); AU.addPreserved<ScalarEvolutionWrapperPass>(); AU.addPreserved<SCEVAAWrapperPass>(); + + // This is needed to perform LCSSA verification inside LPPassManager + AU.addRequired<LCSSAVerificationPass>(); + AU.addPreserved<LCSSAVerificationPass>(); } }; } @@ -351,6 +371,7 @@ INITIALIZE_PASS_BEGIN(LCSSAWrapperPass, "lcssa", "Loop-Closed SSA Form Pass", false, false) INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass) INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass) +INITIALIZE_PASS_DEPENDENCY(LCSSAVerificationPass) INITIALIZE_PASS_END(LCSSAWrapperPass, "lcssa", "Loop-Closed SSA Form Pass", false, false) |
