From 9184b25fa543a900463215c11635c2c014ddb623 Mon Sep 17 00:00:00 2001 From: Anton Korobeynikov Date: Mon, 15 Feb 2010 22:35:59 +0000 Subject: Preliminary patch to improve dwarf EH generation - Hooks to return Personality / FDE / LSDA / TType encoding depending on target / options (e.g. code model / relocation model) - MCIzation of Dwarf EH printer to use encoding information - Stub generation for ELF target (needed for indirect references) - Some other small changes here and there git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96285 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/PowerPC/PPCTargetMachine.cpp | 29 ----------------------------- 1 file changed, 29 deletions(-) (limited to 'lib/Target/PowerPC/PPCTargetMachine.cpp') diff --git a/lib/Target/PowerPC/PPCTargetMachine.cpp b/lib/Target/PowerPC/PPCTargetMachine.cpp index 22eecd4fea..cac69622ca 100644 --- a/lib/Target/PowerPC/PPCTargetMachine.cpp +++ b/lib/Target/PowerPC/PPCTargetMachine.cpp @@ -115,32 +115,3 @@ bool PPCTargetMachine::addCodeEmitter(PassManagerBase &PM, return false; } - -/// getLSDAEncoding - Returns the LSDA pointer encoding. The choices are 4-byte, -/// 8-byte, and target default. The CIE is hard-coded to indicate that the LSDA -/// pointer in the FDE section is an "sdata4", and should be encoded as a 4-byte -/// pointer by default. However, some systems may require a different size due -/// to bugs or other conditions. We will default to a 4-byte encoding unless the -/// system tells us otherwise. -/// -/// The issue is when the CIE says their is an LSDA. That mandates that every -/// FDE have an LSDA slot. But if the function does not need an LSDA. There -/// needs to be some way to signify there is none. The LSDA is encoded as -/// pc-rel. But you don't look for some magic value after adding the pc. You -/// have to look for a zero before adding the pc. The problem is that the size -/// of the zero to look for depends on the encoding. The unwinder bug in SL is -/// that it always checks for a pointer-size zero. So on x86_64 it looks for 8 -/// bytes of zero. If you have an LSDA, it works fine since the 8-bytes are -/// non-zero so it goes ahead and then reads the value based on the encoding. -/// But if you use sdata4 and there is no LSDA, then the test for zero gives a -/// false negative and the unwinder thinks there is an LSDA. -/// -/// FIXME: This call-back isn't good! We should be using the correct encoding -/// regardless of the system. However, there are some systems which have bugs -/// that prevent this from occuring. -DwarfLSDAEncoding::Encoding PPCTargetMachine::getLSDAEncoding() const { - if (Subtarget.isDarwin() && Subtarget.getDarwinVers() != 10) - return DwarfLSDAEncoding::Default; - - return DwarfLSDAEncoding::EightByte; -} -- cgit v1.2.3