From bb166bed40e4099bfaac1f3dbda5bbfcac724630 Mon Sep 17 00:00:00 2001 From: Daniel Dunbar Date: Mon, 17 May 2010 21:54:30 +0000 Subject: MC/Mach-O/x86: Optimal nop sequences should only be used for the .text sections, not all sections in the text segment. llvm-svn: 103981 --- llvm/lib/MC/MCParser/AsmParser.cpp | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'llvm/lib/MC/MCParser/AsmParser.cpp') diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp index 0df839b84d9..c4916731ef0 100644 --- a/llvm/lib/MC/MCParser/AsmParser.cpp +++ b/llvm/lib/MC/MCParser/AsmParser.cpp @@ -1178,10 +1178,8 @@ bool AsmParser::ParseDirectiveAlign(bool IsPow2, unsigned ValueSize) { Lex(); - if (!HasFillExpr) { - // FIXME: Sometimes fill with nop. + if (!HasFillExpr) FillExpr = 0; - } // Compute alignment in bytes. if (IsPow2) { @@ -1209,14 +1207,21 @@ bool AsmParser::ParseDirectiveAlign(bool IsPow2, unsigned ValueSize) { } } - // FIXME: hard code the parser to use EmitCodeAlignment for text when using - // the TextAlignFillValue. - if(Out.getCurrentSection()->getKind().isText() && - Lexer.getMAI().getTextAlignFillValue() == FillExpr) + // Check whether we should use optimal code alignment for this .align + // directive. + // + // FIXME: This should be using a target hook. + bool UseCodeAlign = false; + if (const MCSectionMachO *S = dyn_cast( + Out.getCurrentSection())) + UseCodeAlign = S->hasAttribute(MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS); + if ((!HasFillExpr || Lexer.getMAI().getTextAlignFillValue() == FillExpr) && + ValueSize == 1 && UseCodeAlign) { Out.EmitCodeAlignment(Alignment, MaxBytesToFill); - else + } else { // FIXME: Target specific behavior about how the "extra" bytes are filled. Out.EmitValueToAlignment(Alignment, FillExpr, ValueSize, MaxBytesToFill); + } return false; } -- cgit v1.2.3