From 29cc6cb4d1aa22f0a27edf4e5b363071a83a65d8 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Tue, 24 Jan 2012 14:17:05 +0000 Subject: C++, CBE, and TLOF support for ConstantDataSequential git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148805 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/TargetLoweringObjectFile.cpp | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) (limited to 'lib/Target/TargetLoweringObjectFile.cpp') diff --git a/lib/Target/TargetLoweringObjectFile.cpp b/lib/Target/TargetLoweringObjectFile.cpp index 70abe5a052..ec3b1946f3 100644 --- a/lib/Target/TargetLoweringObjectFile.cpp +++ b/lib/Target/TargetLoweringObjectFile.cpp @@ -73,12 +73,12 @@ static bool isSuitableForBSS(const GlobalVariable *GV, bool NoZerosInBSS) { /// IsNullTerminatedString - Return true if the specified constant (which is /// known to have a type that is an array of 1/2/4 byte elements) ends with a -/// nul value and contains no other nuls in it. +/// nul value and contains no other nuls in it. Note that this is more general +/// than ConstantDataSequential::isString because we allow 2 & 4 byte strings. static bool IsNullTerminatedString(const Constant *C) { - ArrayType *ATy = cast(C->getType()); - - // First check: is we have constant array of i8 terminated with zero + // First check: is we have constant array terminated with zero if (const ConstantArray *CVA = dyn_cast(C)) { + ArrayType *ATy = cast(C->getType()); if (ATy->getNumElements() == 0) return false; ConstantInt *Null = @@ -94,10 +94,23 @@ static bool IsNullTerminatedString(const Constant *C) { return false; return true; } + if (const ConstantDataSequential *CDS = dyn_cast(C)) { + unsigned NumElts = CDS->getNumElements(); + assert(NumElts != 0 && "Can't have an empty CDS"); + + if (CDS->getElementAsInteger(NumElts-1) != 0) + return false; // Not null terminated. + + // Verify that the null doesn't occur anywhere else in the string. + for (unsigned i = 0; i != NumElts-1; ++i) + if (CDS->getElementAsInteger(i) == 0) + return false; + return true; + } // Another possibility: [1 x i8] zeroinitializer if (isa(C)) - return ATy->getNumElements() == 1; + return cast(C->getType())->getNumElements() == 1; return false; } -- cgit v1.2.3-70-g09d2