From e2921432b6e0ba916ebfca312ae2cac7641279ec Mon Sep 17 00:00:00 2001 From: John McCall Date: Thu, 29 Jul 2010 09:04:45 +0000 Subject: [PATCH] Diagnose non-structural differences in the case where blocks were structurally identical. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109743 91177308-0d34-0410-b5e6-96231b3b80d8 --- tools/llvm-diff/DifferenceEngine.cpp | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/tools/llvm-diff/DifferenceEngine.cpp b/tools/llvm-diff/DifferenceEngine.cpp index d9fbc57d2d7..764b56a296a 100644 --- a/tools/llvm-diff/DifferenceEngine.cpp +++ b/tools/llvm-diff/DifferenceEngine.cpp @@ -194,7 +194,7 @@ class FunctionDifferenceEngine { // If the instructions differ, start the more sophisticated diff // algorithm at the start of the block. - if (diff(LeftI, RightI, false, true)) { + if (diff(LeftI, RightI, false, false)) { TentativeValues.clear(); return runBlockDiff(L->begin(), R->begin()); } @@ -207,11 +207,22 @@ class FunctionDifferenceEngine { } while (LI != LE); // This is sufficient: we can't get equality of // terminators if there are residual instructions. - // Make all the tentative pairs solid. - for (llvm::DenseSet >::iterator - I = TentativeValues.begin(), E = TentativeValues.end(); I != E; ++I) - Values[I->first] = I->second; TentativeValues.clear(); + + // Do another pass over the block, this time in complaints mode. + LI = L->begin(); RI = R->begin(); + do { + assert(LI != LE && RI != RE); + bool Result = diff(&*LI, &*RI, true, true); + assert(!Result && "structural differences second time around?"); + (void) Result; + + // Make the mapping non-tentative this time. + if (!LI->use_empty()) + Values[&*LI] = &*RI; + + ++LI, ++RI; + } while (LI != LE); } bool matchForBlockDiff(Instruction *L, Instruction *R); -- 2.34.1