Update libunwind to LLVM 17.0.4 (#20705)

Author: aheejin

system/lib/libunwind/include/__libunwind_config.h

@@ -196,9 +196,9 @@
 # define _LIBUNWIND_TARGET_RISCV 1
 # define _LIBUNWIND_TARGET_VE 1
 # define _LIBUNWIND_TARGET_S390X 1
-#define _LIBUNWIND_TARGET_LOONGARCH 1
+ #define _LIBUNWIND_TARGET_LOONGARCH 1
 # define _LIBUNWIND_CONTEXT_SIZE 167
-# define _LIBUNWIND_CURSOR_SIZE 179
+# define _LIBUNWIND_CURSOR_SIZE 204
 # define _LIBUNWIND_HIGHEST_DWARF_REGISTER 287
 #endif // _LIBUNWIND_IS_NATIVE_ONLY
 

system/lib/libunwind/readme.txt

@@ -1,14 +1,14 @@
 llvm's libunwind
 ----------------
 
-These files are from the llvm-project based on release 16.0.6.
+These files are from the llvm-project based on release 17.0.4.
 
 We maintain a local fork of llvm-project that contains any emscripten
 specific patches:
 
   https://github.com/emscripten-core/llvm-project
 
-The current patch is based on the emscripten-libs-16 branch.
+The current patch is based on the emscripten-libs-17 branch.
 
 Update Instructions
 -------------------
@@ -20,4 +20,4 @@ Modifications
 
 For a list of changes from upstream see the libunwind files that are part of:
 
-https://github.com/llvm/llvm-project/compare/llvmorg-16.0.6...emscripten-core:emscripten-libs-16
+https://github.com/llvm/llvm-project/compare/llvmorg-17.0.4...emscripten-core:emscripten-libs-17

system/lib/libunwind/src/AddressSpace.hpp

@@ -66,6 +66,10 @@ char *getFuncNameFromTBTable(uintptr_t pc, uint16_t &NameLen,
   // In 10.7.0 or later, libSystem.dylib implements this function.
   extern "C" bool _dyld_find_unwind_sections(void *, dyld_unwind_sections *);
 
+namespace libunwind {
+  bool findDynamicUnwindSections(void *, unw_dynamic_unwind_sections *);
+}
+
 #elif defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) && defined(_LIBUNWIND_IS_BAREMETAL)
 
 // When statically linked on bare-metal, the symbols for the EH table are looked
@@ -497,6 +501,22 @@ inline bool LocalAddressSpace::findUnwindSections(pint_t targetAddr,
     info.compact_unwind_section_length = (size_t)dyldInfo.compact_unwind_section_length;
     return true;
   }
+
+  unw_dynamic_unwind_sections dynamicUnwindSectionInfo;
+  if (findDynamicUnwindSections((void *)targetAddr,
+                                &dynamicUnwindSectionInfo)) {
+    info.dso_base = dynamicUnwindSectionInfo.dso_base;
+#if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
+    info.dwarf_section = (uintptr_t)dynamicUnwindSectionInfo.dwarf_section;
+    info.dwarf_section_length = dynamicUnwindSectionInfo.dwarf_section_length;
+#endif
+    info.compact_unwind_section =
+        (uintptr_t)dynamicUnwindSectionInfo.compact_unwind_section;
+    info.compact_unwind_section_length =
+        dynamicUnwindSectionInfo.compact_unwind_section_length;
+    return true;
+  }
+
 #elif defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) && defined(_LIBUNWIND_IS_BAREMETAL)
   info.dso_base = 0;
   // Bare metal is statically linked, so no need to ask the dynamic loader

system/lib/libunwind/src/Unwind-EHABI.cpp

@@ -709,7 +709,7 @@ unwind_phase2_forced(unw_context_t *uc, unw_cursor_t *cursor,
     // Update info about this frame.
     unw_proc_info_t frameInfo;
     if (__unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): __unw_step "
+      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): __unw_get_proc_info "
                                  "failed => _URC_END_OF_STACK",
                                  (void *)exception_object);
       return _URC_FATAL_PHASE2_ERROR;
@@ -885,8 +885,11 @@ _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
   return result;
 }
 
-static uint64_t ValueAsBitPattern(_Unwind_VRS_DataRepresentation representation,
-                                  void* valuep) {
+// Only used in _LIBUNWIND_TRACE_API, which is a no-op when assertions are
+// disabled.
+[[gnu::unused]] static uint64_t
+ValueAsBitPattern(_Unwind_VRS_DataRepresentation representation,
+                  const void *valuep) {
   uint64_t value = 0;
   switch (representation) {
     case _UVRSD_UINT32:

system/lib/libunwind/src/Unwind-seh.cpp

@@ -212,11 +212,20 @@ __libunwind_seh_personality(int version, _Unwind_Action state,
   ms_exc.ExceptionInformation[2] = state;
   DISPATCHER_CONTEXT *disp_ctx =
       __unw_seh_get_disp_ctx((unw_cursor_t *)context);
+  _LIBUNWIND_TRACE_UNWINDING("__libunwind_seh_personality() calling "
+                             "LanguageHandler %p(%p, %p, %p, %p)",
+                             (void *)disp_ctx->LanguageHandler, (void *)&ms_exc,
+                             (void *)disp_ctx->EstablisherFrame,
+                             (void *)disp_ctx->ContextRecord, (void *)disp_ctx);
   EXCEPTION_DISPOSITION ms_act = disp_ctx->LanguageHandler(&ms_exc,
                                                            (PVOID)disp_ctx->EstablisherFrame,
                                                            disp_ctx->ContextRecord,
                                                            disp_ctx);
+  _LIBUNWIND_TRACE_UNWINDING("__libunwind_seh_personality() LanguageHandler "
+                             "returned %d",
+                             (int)ms_act);
   switch (ms_act) {
+  case ExceptionContinueExecution: return _URC_END_OF_STACK;
   case ExceptionContinueSearch: return _URC_CONTINUE_UNWIND;
   case 4 /*ExceptionExecuteHandler*/:
     return phase2 ? _URC_INSTALL_CONTEXT : _URC_HANDLER_FOUND;
@@ -238,7 +247,7 @@ unwind_phase2_forced(unw_context_t *uc,
     // Update info about this frame.
     unw_proc_info_t frameInfo;
     if (__unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
-      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): __unw_step "
+      _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): __unw_get_proc_info "
                                  "failed => _URC_END_OF_STACK",
                                  (void *)exception_object);
       return _URC_FATAL_PHASE2_ERROR;
@@ -304,6 +313,12 @@ unwind_phase2_forced(unw_context_t *uc,
         // We may get control back if landing pad calls _Unwind_Resume().
         __unw_resume(&cursor2);
         break;
+      case _URC_END_OF_STACK:
+        _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
+                                   "personality returned "
+                                   "_URC_END_OF_STACK",
+                                   (void *)exception_object);
+        break;
       default:
         // Personality routine returned an unknown result code.
         _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
@@ -312,6 +327,8 @@ unwind_phase2_forced(unw_context_t *uc,
                                    (void *)exception_object, personalityResult);
         return _URC_FATAL_PHASE2_ERROR;
       }
+      if (personalityResult == _URC_END_OF_STACK)
+        break;
     }
   }
 

system/lib/libunwind/src/UnwindCursor.hpp

@@ -31,7 +31,8 @@
 #endif
 
 #if defined(_LIBUNWIND_TARGET_LINUX) &&                                        \
-    (defined(_LIBUNWIND_TARGET_AARCH64) || defined(_LIBUNWIND_TARGET_S390X))
+    (defined(_LIBUNWIND_TARGET_AARCH64) || defined(_LIBUNWIND_TARGET_RISCV) || \
+     defined(_LIBUNWIND_TARGET_S390X))
 #include <sys/syscall.h>
 #include <sys/uio.h>
 #include <unistd.h>
@@ -506,7 +507,14 @@ class UnwindCursor : public AbstractUnwindCursor {
 #endif
 
   DISPATCHER_CONTEXT *getDispatcherContext() { return &_dispContext; }
-  void setDispatcherContext(DISPATCHER_CONTEXT *disp) { _dispContext = *disp; }
+  void setDispatcherContext(DISPATCHER_CONTEXT *disp) {
+    _dispContext = *disp;
+    _info.lsda = reinterpret_cast<unw_word_t>(_dispContext.HandlerData);
+    if (_dispContext.LanguageHandler) {
+      _info.handler = reinterpret_cast<unw_word_t>(__libunwind_seh_personality);
+    } else
+      _info.handler = 0;
+  }
 
   // libunwind does not and should not depend on C++ library which means that we
   // need our own definition of inline placement new.
@@ -568,10 +576,12 @@ UnwindCursor<A, R>::UnwindCursor(unw_context_t *context, A &as)
                 "UnwindCursor<> requires more alignment than unw_cursor_t");
   memset(&_info, 0, sizeof(_info));
   memset(&_histTable, 0, sizeof(_histTable));
+  memset(&_dispContext, 0, sizeof(_dispContext));
   _dispContext.ContextRecord = &_msContext;
   _dispContext.HistoryTable = &_histTable;
   // Initialize MS context from ours.
   R r(context);
+  RtlCaptureContext(&_msContext);
   _msContext.ContextFlags = CONTEXT_CONTROL|CONTEXT_INTEGER|CONTEXT_FLOATING_POINT;
 #if defined(_LIBUNWIND_TARGET_X86_64)
   _msContext.Rax = r.getRegister(UNW_X86_64_RAX);
@@ -669,6 +679,7 @@ UnwindCursor<A, R>::UnwindCursor(CONTEXT *context, A &as)
                 "UnwindCursor<> does not fit in unw_cursor_t");
   memset(&_info, 0, sizeof(_info));
   memset(&_histTable, 0, sizeof(_histTable));
+  memset(&_dispContext, 0, sizeof(_dispContext));
   _dispContext.ContextRecord = &_msContext;
   _dispContext.HistoryTable = &_histTable;
   _msContext = *context;
@@ -679,7 +690,7 @@ template <typename A, typename R>
 bool UnwindCursor<A, R>::validReg(int regNum) {
   if (regNum == UNW_REG_IP || regNum == UNW_REG_SP) return true;
 #if defined(_LIBUNWIND_TARGET_X86_64)
-  if (regNum >= UNW_X86_64_RAX && regNum <= UNW_X86_64_R15) return true;
+  if (regNum >= UNW_X86_64_RAX && regNum <= UNW_X86_64_RIP) return true;
 #elif defined(_LIBUNWIND_TARGET_ARM)
   if ((regNum >= UNW_ARM_R0 && regNum <= UNW_ARM_R15) ||
       regNum == UNW_ARM_RA_AUTH_CODE)
@@ -694,6 +705,7 @@ template <typename A, typename R>
 unw_word_t UnwindCursor<A, R>::getReg(int regNum) {
   switch (regNum) {
 #if defined(_LIBUNWIND_TARGET_X86_64)
+  case UNW_X86_64_RIP:
   case UNW_REG_IP: return _msContext.Rip;
   case UNW_X86_64_RAX: return _msContext.Rax;
   case UNW_X86_64_RDX: return _msContext.Rdx;
@@ -744,6 +756,7 @@ template <typename A, typename R>
 void UnwindCursor<A, R>::setReg(int regNum, unw_word_t value) {
   switch (regNum) {
 #if defined(_LIBUNWIND_TARGET_X86_64)
+  case UNW_X86_64_RIP:
   case UNW_REG_IP: _msContext.Rip = value; break;
   case UNW_X86_64_RAX: _msContext.Rax = value; break;
   case UNW_X86_64_RDX: _msContext.Rdx = value; break;
@@ -981,6 +994,10 @@ class UnwindCursor : public AbstractUnwindCursor{
   bool setInfoForSigReturn(Registers_arm64 &);
   int stepThroughSigReturn(Registers_arm64 &);
 #endif
+#if defined(_LIBUNWIND_TARGET_RISCV)
+  bool setInfoForSigReturn(Registers_riscv &);
+  int stepThroughSigReturn(Registers_riscv &);
+#endif
 #if defined(_LIBUNWIND_TARGET_S390X)
   bool setInfoForSigReturn(Registers_s390x &);
   int stepThroughSigReturn(Registers_s390x &);
@@ -1978,6 +1995,9 @@ bool UnwindCursor<A, R>::getInfoFromSEH(pint_t pc) {
       uint32_t lastcode = (xdata->CountOfCodes + 1) & ~1;
       const uint32_t *handler = reinterpret_cast<uint32_t *>(&xdata->UnwindCodes[lastcode]);
       _info.lsda = reinterpret_cast<unw_word_t>(handler+1);
+      _dispContext.HandlerData = reinterpret_cast<void *>(_info.lsda);
+      _dispContext.LanguageHandler =
+          reinterpret_cast<EXCEPTION_ROUTINE *>(base + *handler);
       if (*handler) {
         _info.handler = reinterpret_cast<unw_word_t>(__libunwind_seh_personality);
       } else
@@ -2705,6 +2725,60 @@ int UnwindCursor<A, R>::stepThroughSigReturn(Registers_arm64 &) {
 #endif // defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) &&
        // defined(_LIBUNWIND_TARGET_AARCH64)
 
+#if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) &&                               \
+    defined(_LIBUNWIND_TARGET_RISCV)
+template <typename A, typename R>
+bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_riscv &) {
+  const pint_t pc = static_cast<pint_t>(getReg(UNW_REG_IP));
+  uint32_t instructions[2];
+  struct iovec local_iov = {&instructions, sizeof instructions};
+  struct iovec remote_iov = {reinterpret_cast<void *>(pc), sizeof instructions};
+  long bytesRead =
+      syscall(SYS_process_vm_readv, getpid(), &local_iov, 1, &remote_iov, 1, 0);
+  // Look for the two instructions used in the sigreturn trampoline
+  // __vdso_rt_sigreturn:
+  //
+  // 0x08b00893 li a7,0x8b
+  // 0x00000073 ecall
+  if (bytesRead != sizeof instructions || instructions[0] != 0x08b00893 ||
+      instructions[1] != 0x00000073)
+    return false;
+
+  _info = {};
+  _info.start_ip = pc;
+  _info.end_ip = pc + 4;
+  _isSigReturn = true;
+  return true;
+}
+
+template <typename A, typename R>
+int UnwindCursor<A, R>::stepThroughSigReturn(Registers_riscv &) {
+  // In the signal trampoline frame, sp points to an rt_sigframe[1], which is:
+  //  - 128-byte siginfo struct
+  //  - ucontext_t struct:
+  //     - 8-byte long (__uc_flags)
+  //     - 8-byte pointer (*uc_link)
+  //     - 24-byte uc_stack
+  //     - 8-byte uc_sigmask
+  //     - 120-byte of padding to allow sigset_t to be expanded in the future
+  //     - 8 bytes of padding because sigcontext has 16-byte alignment
+  //     - struct sigcontext uc_mcontext
+  // [1]
+  // https://github.com/torvalds/linux/blob/master/arch/riscv/kernel/signal.c
+  const pint_t kOffsetSpToSigcontext = 128 + 8 + 8 + 24 + 8 + 128;
+
+  const pint_t sigctx = _registers.getSP() + kOffsetSpToSigcontext;
+  _registers.setIP(_addressSpace.get64(sigctx));
+  for (int i = UNW_RISCV_X1; i <= UNW_RISCV_X31; ++i) {
+    uint64_t value = _addressSpace.get64(sigctx + static_cast<pint_t>(i * 8));
+    _registers.setRegister(i, value);
+  }
+  _isSignalFrame = true;
+  return UNW_STEP_SUCCESS;
+}
+#endif // defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) &&
+       // defined(_LIBUNWIND_TARGET_RISCV)
+
 #if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) &&                               \
     defined(_LIBUNWIND_TARGET_S390X)
 template <typename A, typename R>

system/lib/libunwind/src/UnwindLevel1-gcc-ext.c

@@ -167,7 +167,7 @@ _Unwind_Backtrace(_Unwind_Trace_Fn callback, void *ref) {
     }
 
     // Update the pr_cache in the mock exception object.
-    const uint32_t* unwindInfo = (uint32_t *) frameInfo.unwind_info;
+    uint32_t *unwindInfo = (uint32_t *)frameInfo.unwind_info;
     ex.pr_cache.fnstart = frameInfo.start_ip;
     ex.pr_cache.ehtp = (_Unwind_EHT_Header *) unwindInfo;
     ex.pr_cache.additional= frameInfo.flags;

system/lib/libunwind/src/UnwindLevel1.c

@@ -321,7 +321,7 @@ unwind_phase2_forced(unw_context_t *uc, unw_cursor_t *cursor,
     unw_proc_info_t frameInfo;
     if (__unw_get_proc_info(cursor, &frameInfo) != UNW_ESUCCESS) {
       _LIBUNWIND_TRACE_UNWINDING(
-          "unwind_phase2_forced(ex_obj=%p): __unw_step_stage2 "
+          "unwind_phase2_forced(ex_obj=%p): __unw_get_proc_info "
           "failed => _URC_END_OF_STACK",
           (void *)exception_object);
       return _URC_FATAL_PHASE2_ERROR;