Update LLVM for 3.5 rebase (r209712).
Change-Id: I149556c940fb7dc92d075273c87ff584f400941f
diff --git a/lib/Transforms/Utils/SimplifyInstructions.cpp b/lib/Transforms/Utils/SimplifyInstructions.cpp
index bbd65f1..33b3637 100644
--- a/lib/Transforms/Utils/SimplifyInstructions.cpp
+++ b/lib/Transforms/Utils/SimplifyInstructions.cpp
@@ -14,7 +14,6 @@
//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "instsimplify"
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/SmallPtrSet.h"
@@ -29,6 +28,8 @@
#include "llvm/Transforms/Utils/Local.h"
using namespace llvm;
+#define DEBUG_TYPE "instsimplify"
+
STATISTIC(NumSimplified, "Number of redundant instructions removed");
namespace {
@@ -47,17 +48,18 @@
bool runOnFunction(Function &F) override {
const DominatorTreeWrapperPass *DTWP =
getAnalysisIfAvailable<DominatorTreeWrapperPass>();
- const DominatorTree *DT = DTWP ? &DTWP->getDomTree() : 0;
+ const DominatorTree *DT = DTWP ? &DTWP->getDomTree() : nullptr;
DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
- const DataLayout *DL = DLP ? &DLP->getDataLayout() : 0;
+ const DataLayout *DL = DLP ? &DLP->getDataLayout() : nullptr;
const TargetLibraryInfo *TLI = &getAnalysis<TargetLibraryInfo>();
SmallPtrSet<const Instruction*, 8> S1, S2, *ToSimplify = &S1, *Next = &S2;
bool Changed = false;
do {
- for (df_iterator<BasicBlock*> DI = df_begin(&F.getEntryBlock()),
- DE = df_end(&F.getEntryBlock()); DI != DE; ++DI)
- for (BasicBlock::iterator BI = DI->begin(), BE = DI->end(); BI != BE;) {
+ for (BasicBlock *BB : depth_first(&F.getEntryBlock()))
+ // Here be subtlety: the iterator must be incremented before the loop
+ // body (not sure why), so a range-for loop won't work here.
+ for (BasicBlock::iterator BI = BB->begin(), BE = BB->end(); BI != BE;) {
Instruction *I = BI++;
// The first time through the loop ToSimplify is empty and we try to
// simplify all instructions. On later iterations ToSimplify is not
@@ -74,7 +76,15 @@
++NumSimplified;
Changed = true;
}
- Changed |= RecursivelyDeleteTriviallyDeadInstructions(I, TLI);
+ bool res = RecursivelyDeleteTriviallyDeadInstructions(I, TLI);
+ if (res) {
+ // RecursivelyDeleteTriviallyDeadInstruction can remove
+ // more than one instruction, so simply incrementing the
+ // iterator does not work. When instructions get deleted
+ // re-iterate instead.
+ BI = BB->begin(); BE = BB->end();
+ Changed |= res;
+ }
}
// Place the list of instructions to simplify on the next loop iteration