From bb96df602ebf7357b24cba5bf4fb09750d467be7 Mon Sep 17 00:00:00 2001 From: Reid Kleckner Date: Wed, 5 Oct 2016 22:36:07 +0000 Subject: [codeview] Truncate records to maximum record size near 64KB If we don't truncate, LLVM asserts when the label difference doesn't fit in a 16 bit field. This patch truncates two kinds of data: trailing null terminated names in symbol records, and inline line tables. The inline line table test that I have is too large (many MB), so I'm not checking it in. Hopefully fixes PR28264. llvm-svn: 283403 --- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp') diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp index 1850a30a5d1..a305e3d3ab9 100644 --- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp +++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp @@ -432,10 +432,13 @@ void CodeViewDebug::endModule() { } static void emitNullTerminatedSymbolName(MCStreamer &OS, StringRef S) { - // Microsoft's linker seems to have trouble with symbol names longer than - // 0xffd8 bytes. - S = S.substr(0, 0xffd8); - SmallString<32> NullTerminatedString(S); + // The maximum CV record length is 0xFF00. Most of the strings we emit appear + // after a fixed length portion of the record. The fixed length portion should + // always be less than 0xF00 (3840) bytes, so truncate the string so that the + // overall record size is less than the maximum allowed. + unsigned MaxFixedRecordLength = 0xF00; + SmallString<32> NullTerminatedString( + S.take_front(MaxRecordLength - MaxFixedRecordLength - 1)); NullTerminatedString.push_back('\0'); OS.EmitBytes(NullTerminatedString); } -- cgit v1.2.3