From e524daa7e8719f4b43e6ebcf25fd4e7d74c5d1c4 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Martin=20Storsj=C3=B6?= Date: Sun, 16 Aug 2020 15:12:55 +0300 Subject: [PATCH] [libunwind] Convert x86, x86_64, arm64 register restore functions to C calling convention and name mangling Currently, the assembly functions for restoring register state have been direct implementations of the Registers_*::jumpto() method (contrary to the functions for saving register state, which are implementations of the extern C function __unw_getcontext). This has included having the assembly function name match the C++ mangling of that method name (and having the function match the C++ member function calling convention). To simplify the interface of the assembly implementations, make the functions have C calling conventions and name mangling. This fixes building the library in with a MSVC C++ ABI with clang-cl, which uses a significantly different method name mangling scheme. (The library might not be of much use as C++ exception unwinder in such an environment, but the libunwind.h interface for stepwise unwinding still is usable, as is the _Unwind_Backtrace function.) Differential Revision: https://reviews.llvm.org/D86041 --- libunwind/src/Registers.hpp | 12 +++++++++--- libunwind/src/UnwindRegistersRestore.S | 17 ++++++----------- 2 files changed, 15 insertions(+), 14 deletions(-) diff --git a/libunwind/src/Registers.hpp b/libunwind/src/Registers.hpp index c76b05b..4d963b4 100644 --- a/libunwind/src/Registers.hpp +++ b/libunwind/src/Registers.hpp @@ -39,6 +39,8 @@ enum { }; #if defined(_LIBUNWIND_TARGET_I386) +class _LIBUNWIND_HIDDEN Registers_x86; +extern "C" void __libunwind_Registers_x86_jumpto(Registers_x86 *); /// Registers_x86 holds the register state of a thread in a 32-bit intel /// process. class _LIBUNWIND_HIDDEN Registers_x86 { @@ -56,7 +58,7 @@ public: v128 getVectorRegister(int num) const; void setVectorRegister(int num, v128 value); static const char *getRegisterName(int num); - void jumpto(); + void jumpto() { __libunwind_Registers_x86_jumpto(this); } static int lastDwarfRegNum() { return _LIBUNWIND_HIGHEST_DWARF_REGISTER_X86; } static int getArch() { return REGISTERS_X86; } @@ -248,6 +250,8 @@ inline void Registers_x86::setVectorRegister(int, v128) { #if defined(_LIBUNWIND_TARGET_X86_64) /// Registers_x86_64 holds the register state of a thread in a 64-bit intel /// process. +class _LIBUNWIND_HIDDEN Registers_x86_64; +extern "C" void __libunwind_Registers_x86_64_jumpto(Registers_x86_64 *); class _LIBUNWIND_HIDDEN Registers_x86_64 { public: Registers_x86_64(); @@ -263,7 +267,7 @@ public: v128 getVectorRegister(int num) const; void setVectorRegister(int num, v128 value); static const char *getRegisterName(int num); - void jumpto(); + void jumpto() { __libunwind_Registers_x86_64_jumpto(this); } static int lastDwarfRegNum() { return _LIBUNWIND_HIGHEST_DWARF_REGISTER_X86_64; } static int getArch() { return REGISTERS_X86_64; } @@ -1771,6 +1775,8 @@ inline const char *Registers_ppc64::getRegisterName(int regNum) { #if defined(_LIBUNWIND_TARGET_AARCH64) /// Registers_arm64 holds the register state of a thread in a 64-bit arm /// process. +class _LIBUNWIND_HIDDEN Registers_arm64; +extern "C" void __libunwind_Registers_arm64_jumpto(Registers_arm64 *); class _LIBUNWIND_HIDDEN Registers_arm64 { public: Registers_arm64(); @@ -1786,7 +1792,7 @@ public: v128 getVectorRegister(int num) const; void setVectorRegister(int num, v128 value); static const char *getRegisterName(int num); - void jumpto(); + void jumpto() { __libunwind_Registers_arm64_jumpto(this); } static int lastDwarfRegNum() { return _LIBUNWIND_HIGHEST_DWARF_REGISTER_ARM64; } static int getArch() { return REGISTERS_ARM64; } diff --git a/libunwind/src/UnwindRegistersRestore.S b/libunwind/src/UnwindRegistersRestore.S index 5d54432..d817e6d 100644 --- a/libunwind/src/UnwindRegistersRestore.S +++ b/libunwind/src/UnwindRegistersRestore.S @@ -13,14 +13,10 @@ #if !defined(__USING_SJLJ_EXCEPTIONS__) #if defined(__i386__) -DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_x866jumptoEv) +DEFINE_LIBUNWIND_FUNCTION(__libunwind_Registers_x86_jumpto) # -# void libunwind::Registers_x86::jumpto() +# extern "C" void __libunwind_Registers_x86_jumpto(Registers_x86 *); # -#if defined(_WIN32) -# On windows, the 'this' pointer is passed in ecx instead of on the stack - movl %ecx, %eax -#else # On entry: # + + # +-----------------------+ @@ -30,7 +26,6 @@ DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_x866jumptoEv) # +-----------------------+ <-- SP # + + movl 4(%esp), %eax -#endif # set up eax and ret on new stack location movl 28(%eax), %edx # edx holds new stack pointer subl $8,%edx @@ -60,9 +55,9 @@ DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind13Registers_x866jumptoEv) #elif defined(__x86_64__) -DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind16Registers_x86_646jumptoEv) +DEFINE_LIBUNWIND_FUNCTION(__libunwind_Registers_x86_64_jumpto) # -# void libunwind::Registers_x86_64::jumpto() +# extern "C" void __libunwind_Registers_x86_64_jumpto(Registers_x86_64 *); # #if defined(_WIN64) # On entry, thread_state pointer is in rcx; move it into rdi @@ -560,13 +555,13 @@ Lnovec: #elif defined(__aarch64__) // -// void libunwind::Registers_arm64::jumpto() +// extern "C" void __libunwind_Registers_arm64_jumpto(Registers_arm64 *); // // On entry: // thread_state pointer is in x0 // .p2align 2 -DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind15Registers_arm646jumptoEv) +DEFINE_LIBUNWIND_FUNCTION(__libunwind_Registers_arm64_jumpto) // skip restore of x0,x1 for now ldp x2, x3, [x0, #0x010] ldp x4, x5, [x0, #0x020] -- 2.7.4