From: Bob Wilson Date: Wed, 16 Nov 2011 07:57:21 +0000 (+0000) Subject: Record landing pads with a SmallSetVector to avoid multiple entries. X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=f1b41dd38d2b2713e3870f384525b020bbac05f6;p=oota-llvm.git Record landing pads with a SmallSetVector to avoid multiple entries. There may be many invokes that share one landing pad, and the previous code would record the landing pad once for each invoke. Besides the wasted effort, a pair of volatile loads gets inserted every time the landing pad is processed. The rest of the code can get optimized away when a landing pad is processed repeatedly, but the volatile loads remain, resulting in code like: LBB35_18: Ltmp483: ldr r2, [r7, #-72] ldr r2, [r7, #-68] ldr r2, [r7, #-72] ldr r2, [r7, #-68] ldr r2, [r7, #-72] ldr r2, [r7, #-68] ldr r2, [r7, #-72] ldr r2, [r7, #-68] ldr r2, [r7, #-72] ldr r2, [r7, #-68] ldr r2, [r7, #-72] ldr r2, [r7, #-68] ldr r2, [r7, #-72] ldr r2, [r7, #-68] ldr r2, [r7, #-72] ldr r2, [r7, #-68] ldr r4, [r7, #-72] ldr r2, [r7, #-68] git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144787 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/lib/CodeGen/SjLjEHPrepare.cpp b/lib/CodeGen/SjLjEHPrepare.cpp index 5d60bc9b751..c8651926c2f 100644 --- a/lib/CodeGen/SjLjEHPrepare.cpp +++ b/lib/CodeGen/SjLjEHPrepare.cpp @@ -30,6 +30,7 @@ #include "llvm/Support/Debug.h" #include "llvm/Support/IRBuilder.h" #include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/SetVector.h" #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/Statistic.h" @@ -364,13 +365,13 @@ void SjLjEHPass::lowerAcrossUnwindEdges(Function &F, bool SjLjEHPass::setupEntryBlockAndCallSites(Function &F) { SmallVector Returns; SmallVector Invokes; - SmallVector LPads; + SmallSetVector LPads; // Look through the terminators of the basic blocks to find invokes. for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) if (InvokeInst *II = dyn_cast(BB->getTerminator())) { Invokes.push_back(II); - LPads.push_back(II->getUnwindDest()->getLandingPadInst()); + LPads.insert(II->getUnwindDest()->getLandingPadInst()); } else if (ReturnInst *RI = dyn_cast(BB->getTerminator())) { Returns.push_back(RI); } @@ -382,7 +383,8 @@ bool SjLjEHPass::setupEntryBlockAndCallSites(Function &F) { lowerIncomingArguments(F); lowerAcrossUnwindEdges(F, Invokes); - Value *FuncCtx = setupFunctionContext(F, LPads); + Value *FuncCtx = + setupFunctionContext(F, makeArrayRef(LPads.begin(), LPads.end())); BasicBlock *EntryBB = F.begin(); Type *Int32Ty = Type::getInt32Ty(F.getContext());