From 224c86ee77c87cb90899041f4ee9027ac79d4fd2 Mon Sep 17 00:00:00 2001 From: Duncan Sands Date: Mon, 29 Sep 2008 13:35:31 +0000 Subject: [PATCH] Tweak some comments. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56784 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/IPO/AddReadAttrs.cpp | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/lib/Transforms/IPO/AddReadAttrs.cpp b/lib/Transforms/IPO/AddReadAttrs.cpp index 3e7d860d1d8..b70bdaf763a 100644 --- a/lib/Transforms/IPO/AddReadAttrs.cpp +++ b/lib/Transforms/IPO/AddReadAttrs.cpp @@ -47,14 +47,14 @@ Pass *llvm::createAddReadAttrsPass() { return new AddReadAttrs(); } bool AddReadAttrs::runOnSCC(const std::vector &SCC) { CallGraph &CG = getAnalysis(); - // Check if any of the functions in the SCC read or write memory. - // If they write memory then just give up. + // Check if any of the functions in the SCC read or write memory. If they + // write memory then they can't be marked readnone or readonly. bool ReadsMemory = false; for (unsigned i = 0, e = SCC.size(); i != e; ++i) { Function *F = SCC[i]->getFunction(); if (F == 0) - // External node - may write memory. + // External node - may write memory. Just give up. return false; if (F->doesNotAccessMemory()) @@ -65,7 +65,7 @@ bool AddReadAttrs::runOnSCC(const std::vector &SCC) { // something that writes memory, so treat them like declarations. if (F->isDeclaration() || F->mayBeOverridden()) { if (!F->onlyReadsMemory()) - // May write memory. + // May write memory. Just give up. return false; ReadsMemory = true; @@ -83,7 +83,9 @@ bool AddReadAttrs::runOnSCC(const std::vector &SCC) { continue; if (II->mayWriteToMemory()) + // Writes memory. Just give up. return false; + ReadsMemory |= II->mayReadFromMemory(); } } -- 2.34.1