From 707d0cef664ae8a3785b9d3d4b4cca1e39bfdead Mon Sep 17 00:00:00 2001 From: Dimitry Andric Date: Thu, 20 Jun 2013 18:25:10 +0000 Subject: [PATCH] Pull in r183984 from llvm trunk: Make PrologEpilogInserter save/restore all callee saved registers in functions which call __builtin_unwind_init() __builtin_unwind_init() is an undocumented gcc intrinsic which has this effect, and is used in libgcc_eh. Goes part of the way toward fixing PR8541. This obsoletes the ugly hack to libgcc's unwind code from r245272, and should also work for other arches, so revert the hack too. --- contrib/gcc/unwind-dw2.c | 12 ------------ contrib/llvm/lib/CodeGen/PrologEpilogInserter.cpp | 4 +++- 2 files changed, 3 insertions(+), 13 deletions(-) diff --git a/contrib/gcc/unwind-dw2.c b/contrib/gcc/unwind-dw2.c index 3306e06b4ef..62c9d091315 100644 --- a/contrib/gcc/unwind-dw2.c +++ b/contrib/gcc/unwind-dw2.c @@ -1438,17 +1438,6 @@ uw_init_context_1 (struct _Unwind_Context *context, context->ra = __builtin_extract_return_addr (outer_ra); } -#if defined(__clang__) && defined(__amd64__) -/* Some versions of clang don't save and restore all callee registers, if a - __builtin_eh_return() intrinsic is used in a function. This is particularly - bad on amd64. For now, use the following ugly hack to force it to assume - those registers are clobbered, when invoking __builtin_eh_return(), so it - will emit code to save and restore them. */ -#define CLOBBER_REGS_HACK \ - __asm __volatile(" " : : : "r15", "r14", "r13", "r12", "rbx", "rdx", "rax"); -#else -#define CLOBBER_REGS_HACK -#endif /* __clang__ */ /* Install TARGET into CURRENT so that we can return to it. This is a macro because __builtin_eh_return must be invoked in the context of @@ -1459,7 +1448,6 @@ uw_init_context_1 (struct _Unwind_Context *context, { \ long offset = uw_install_context_1 ((CURRENT), (TARGET)); \ void *handler = __builtin_frob_return_addr ((TARGET)->ra); \ - CLOBBER_REGS_HACK \ __builtin_eh_return (offset, handler); \ } \ while (0) diff --git a/contrib/llvm/lib/CodeGen/PrologEpilogInserter.cpp b/contrib/llvm/lib/CodeGen/PrologEpilogInserter.cpp index 959dd7df58e..9487cbdb96a 100644 --- a/contrib/llvm/lib/CodeGen/PrologEpilogInserter.cpp +++ b/contrib/llvm/lib/CodeGen/PrologEpilogInserter.cpp @@ -29,6 +29,7 @@ #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineInstr.h" #include "llvm/CodeGen/MachineLoopInfo.h" +#include "llvm/CodeGen/MachineModuleInfo.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/RegisterScavenging.h" #include "llvm/IR/InlineAsm.h" @@ -214,7 +215,8 @@ void PEI::calculateCalleeSavedRegisters(MachineFunction &F) { std::vector CSI; for (unsigned i = 0; CSRegs[i]; ++i) { unsigned Reg = CSRegs[i]; - if (F.getRegInfo().isPhysRegUsed(Reg)) { + // Functions which call __builtin_unwind_init get all their registers saved. + if (F.getRegInfo().isPhysRegUsed(Reg) || F.getMMI().callsUnwindInit()) { // If the reg is modified, save it! CSI.push_back(CalleeSavedInfo(Reg)); }