[libunwind] Use uint64_t for unw_word_t in ARM EHABI

[mstorsjo]

Summary

This reduces the differences between the EHABI and DWARF cases.

This allows getting rid of some casts in _LIBUNWIND_TRACE_API log lines, making them match what's in UnwindLevel1.c for DWARF.

The only non-obvious detail is in _Unwind_VRS_Get_Internal (called via _Unwind_VRS_Get), where a void pointer is assumed to be uint32_t or uintptr_t (depending on the caller); this can no longer use unw_word_t directly as before.

[compnerd]

I dont think that this is correct. IIRC, the unwind specification expects unw_word_t to match uintptr_t (that is, it should be 32-bits on P32 environments).

[mstorsjo]

In D39280#908825, @compnerd wrote:

I dont think that this is correct. IIRC, the unwind specification expects unw_word_t to match uintptr_t (that is, it should be 32-bits on P32 environments).

Ok, well currently it doesn't, on 32 bit x86 and ppc at least.

[mstorsjo]

In D39280#908825, @compnerd wrote:

I dont think that this is correct. IIRC, the unwind specification expects unw_word_t to match uintptr_t (that is, it should be 32-bits on P32 environments).

I checked with GNU libunwind, and that seems to be true there. Updating our libunwind to match that doesn't seem to be too hard.

[mstorsjo]

This was made obsolete by D39365.

include/__libunwind_config.h

 #  define _LIBUNWIND_TARGET_AARCH64 1
 #  define _LIBUNWIND_CONTEXT_SIZE 66
 #  define _LIBUNWIND_CURSOR_SIZE 78
 #  define _LIBUNWIND_HIGHEST_DWARF_REGISTER 96
 # elif defined(__arm__)
 #  define _LIBUNWIND_TARGET_ARM 1
 #  if defined(__ARM_WMMX)
 #    define _LIBUNWIND_CONTEXT_SIZE 61
-#    define _LIBUNWIND_CURSOR_SIZE 68
+#    define _LIBUNWIND_CURSOR_SIZE 72
 #  else
 #    define _LIBUNWIND_CONTEXT_SIZE 42
-#    define _LIBUNWIND_CURSOR_SIZE 49
+#    define _LIBUNWIND_CURSOR_SIZE 53
 #  endif
 #  define _LIBUNWIND_HIGHEST_DWARF_REGISTER 96
 # elif defined(__or1k__)
 #  define _LIBUNWIND_TARGET_OR1K 1
 #  define _LIBUNWIND_CONTEXT_SIZE 16
 #  define _LIBUNWIND_CURSOR_SIZE 28
 #  define _LIBUNWIND_HIGHEST_DWARF_REGISTER 32
 # else

include/libunwind.h

 struct unw_cursor_t {
   uint64_t data[_LIBUNWIND_CURSOR_SIZE];
 };
 typedef struct unw_cursor_t unw_cursor_t;
 
 typedef struct unw_addr_space *unw_addr_space_t;
 
 typedef int unw_regnum_t;
+typedef uint64_t unw_word_t;
 #if defined(_LIBUNWIND_ARM_EHABI)
-typedef uint32_t unw_word_t;
 typedef uint64_t unw_fpreg_t;
 #else
-typedef uint64_t unw_word_t;
 typedef double unw_fpreg_t;
 #endif
 
 struct unw_proc_info_t {
   unw_word_t  start_ip;         /* start address of function */
   unw_word_t  end_ip;           /* address after end of function */
   unw_word_t  lsda;             /* address of language specific data area, */
                                 /*  or zero if not used */

src/Unwind-EHABI.cpp

 //===--------------------------- Unwind-EHABI.cpp -------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is dual licensed under the MIT and the University of Illinois Open
 // Source Licenses. See LICENSE.TXT for details.
 //
 //
 //  Implements ARM zero-cost C++ exceptions
 //
 //===----------------------------------------------------------------------===//
 
 #include "Unwind-EHABI.h"
 
 #if defined(_LIBUNWIND_ARM_EHABI)
 
+#include <inttypes.h>
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include <type_traits>
 
if (_LIBUNWIND_TRACING_UNWINDING) {
       unw_word_t offset;
       if ((unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
                              &offset) != UNW_ESUCCESS) ||
           (frameInfo.start_ip + offset > frameInfo.end_ip))
         functionName = ".anonymous.";
       unw_word_t pc;
       unw_get_reg(cursor, UNW_REG_IP, &pc);
       _LIBUNWIND_TRACE_UNWINDING(
-          "unwind_phase1(ex_ojb=%p): pc=0x%llX, start_ip=0x%llX, func=%s, "
-          "lsda=0x%llX, personality=0x%llX",
-          static_cast<void *>(exception_object), (long long)pc,
-          (long long)frameInfo.start_ip, functionName,
-          (long long)frameInfo.lsda, (long long)frameInfo.handler);
+          "unwind_phase1(ex_ojb=%p): pc=0x%" PRIX64 ", start_ip=0x%" PRIX64 " func=%s, "
+          "lsda=0x" PRIX64 ", personality=0x" PRIX64 "",
+          static_cast<void *>(exception_object), pc,
+          frameInfo.start_ip, functionName,
+          frameInfo.lsda, frameInfo.handler);
     }
 
     // If there is a personality routine, ask it if it will want to stop at
     // this frame.
     if (frameInfo.handler != 0) {
       __personality_routine p =
           (__personality_routine)(long)(frameInfo.handler);
       _LIBUNWIND_TRACE_UNWINDING(
if (_LIBUNWIND_TRACING_UNWINDING) {
       char functionBuf[512];
       const char *functionName = functionBuf;
       unw_word_t offset;
       if ((unw_get_proc_name(cursor, functionBuf, sizeof(functionBuf),
                              &offset) != UNW_ESUCCESS) ||
           (frameInfo.start_ip + offset > frameInfo.end_ip))
         functionName = ".anonymous.";
       _LIBUNWIND_TRACE_UNWINDING(
-          "unwind_phase2(ex_ojb=%p): start_ip=0x%llX, func=%s, sp=0x%llX, "
-          "lsda=0x%llX, personality=0x%llX",
-          static_cast<void *>(exception_object), (long long)frameInfo.start_ip,
-          functionName, (long long)sp, (long long)frameInfo.lsda,
-          (long long)frameInfo.handler);
+          "unwind_phase2(ex_ojb=%p): start_ip=0x%" PRIX64 " func=%s, sp=0x%" PRIX64 ", "
+          "lsda=0x%" PRIX64 ", personality=0x%" PRIX64 "",
+          static_cast<void *>(exception_object), frameInfo.start_ip,
+          functionName, sp, frameInfo.lsda,
+          frameInfo.handler);
     }
 
     // If there is a personality routine, tell it we are unwinding.
     if (frameInfo.handler != 0) {
       __personality_routine p =
           (__personality_routine)(long)(frameInfo.handler);
       struct _Unwind_Context *context = (struct _Unwind_Context *)(cursor);
       // EHABI #7.2
if (frameInfo.handler != 0) {
             static_cast<void *>(exception_object));
         // Personality routine says to transfer control to landing pad.
         // We may get control back if landing pad calls _Unwind_Resume().
         if (_LIBUNWIND_TRACING_UNWINDING) {
           unw_word_t pc;
           unw_get_reg(cursor, UNW_REG_IP, &pc);
           unw_get_reg(cursor, UNW_REG_SP, &sp);
           _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): re-entering "
-                                     "user code with ip=0x%llX, sp=0x%llX",
+                                     "user code with ip=0x%" PRIX64 ", sp=0x%" PRIX64 "",
                                      static_cast<void *>(exception_object),
-                                     (long long)pc, (long long)sp);
+                                     pc, sp);
         }
 
         {
           // EHABI #7.4.1 says we need to preserve pc for when _Unwind_Resume
           // is called back, to find this same frame.
           unw_word_t pc;
           unw_get_reg(cursor, UNW_REG_IP, &pc);
           exception_object->unwinder_cache.reserved2 = (uint32_t)pc;

 _LIBUNWIND_EXPORT uintptr_t
 _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   unw_proc_info_t frameInfo;
   uintptr_t result = 0;
   if (unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
     result = (uintptr_t)frameInfo.lsda;
   _LIBUNWIND_TRACE_API(
-      "_Unwind_GetLanguageSpecificData(context=%p) => 0x%llx",
-      static_cast<void *>(context), (long long)result);
+      "_Unwind_GetLanguageSpecificData(context=%p) => 0x%" PRIx64 "",
+      static_cast<void *>(context), result);
   return result;
 }
 
 static uint64_t ValueAsBitPattern(_Unwind_VRS_DataRepresentation representation,
                                   void* valuep) {
   uint64_t value = 0;
   switch (representation) {
     case _UVRSD_UINT32:
_LIBUNWIND_TRACE_API("_Unwind_VRS_Set(context=%p, regclass=%d, reg=%d, "
                        representation,
                        ValueAsBitPattern(representation, valuep));
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   switch (regclass) {
     case _UVRSC_CORE:
       if (representation != _UVRSD_UINT32 || regno > 15)
         return _UVRSR_FAILED;
       return unw_set_reg(cursor, (unw_regnum_t)(UNW_ARM_R0 + regno),
-                         *(unw_word_t *)valuep) == UNW_ESUCCESS
+                         *(uintptr_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
     case _UVRSC_VFP:
       if (representation != _UVRSD_VFPX && representation != _UVRSD_DOUBLE)
         return _UVRSR_FAILED;
       if (representation == _UVRSD_VFPX) {
         // Can only touch d0-15 with FSTMFDX.
         if (regno > 15)
           return _UVRSR_FAILED;
         unw_save_vfp_as_X(cursor);
       } else {
         if (regno > 31)
           return _UVRSR_FAILED;
       }
       return unw_set_fpreg(cursor, (unw_regnum_t)(UNW_ARM_D0 + regno),
                            *(unw_fpreg_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
 #if defined(__ARM_WMMX)
     case _UVRSC_WMMXC:
       if (representation != _UVRSD_UINT32 || regno > 3)
         return _UVRSR_FAILED;
       return unw_set_reg(cursor, (unw_regnum_t)(UNW_ARM_WC0 + regno),
-                         *(unw_word_t *)valuep) == UNW_ESUCCESS
+                         *(uintptr_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
     case _UVRSC_WMMXD:
       if (representation != _UVRSD_DOUBLE || regno > 31)
         return _UVRSR_FAILED;
       return unw_set_fpreg(cursor, (unw_regnum_t)(UNW_ARM_WR0 + regno),
                            *(unw_fpreg_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
 #else
     case _UVRSC_WMMXC:
     case _UVRSC_WMMXD:
       break;
 #endif
   }
   _LIBUNWIND_ABORT("unsupported register class");
 }
 
 static _Unwind_VRS_Result
 _Unwind_VRS_Get_Internal(_Unwind_Context *context,
                          _Unwind_VRS_RegClass regclass, uint32_t regno,
                          _Unwind_VRS_DataRepresentation representation,
                          void *valuep) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
+  unw_word_t word;
+  _Unwind_VRS_Result ret;
   switch (regclass) {
     case _UVRSC_CORE:
       if (representation != _UVRSD_UINT32 || regno > 15)
         return _UVRSR_FAILED;
-      return unw_get_reg(cursor, (unw_regnum_t)(UNW_ARM_R0 + regno),
-                         (unw_word_t *)valuep) == UNW_ESUCCESS
+      ret = unw_get_reg(cursor, (unw_regnum_t)(UNW_ARM_R0 + regno),
+                         &word) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
+      *(uintptr_t *)valuep = word;
+      return ret;
     case _UVRSC_VFP:
       if (representation != _UVRSD_VFPX && representation != _UVRSD_DOUBLE)
         return _UVRSR_FAILED;
       if (representation == _UVRSD_VFPX) {
         // Can only touch d0-15 with FSTMFDX.
         if (regno > 15)
           return _UVRSR_FAILED;
         unw_save_vfp_as_X(cursor);
       } else {
         if (regno > 31)
           return _UVRSR_FAILED;
       }
       return unw_get_fpreg(cursor, (unw_regnum_t)(UNW_ARM_D0 + regno),
                            (unw_fpreg_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
 #if defined(__ARM_WMMX)
     case _UVRSC_WMMXC:
       if (representation != _UVRSD_UINT32 || regno > 3)
         return _UVRSR_FAILED;
-      return unw_get_reg(cursor, (unw_regnum_t)(UNW_ARM_WC0 + regno),
-                         (unw_word_t *)valuep) == UNW_ESUCCESS
+      ret = unw_get_reg(cursor, (unw_regnum_t)(UNW_ARM_WC0 + regno),
+                         &word) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
+      *(uintptr_t *)valuep = word;
+      return ret;
     case _UVRSC_WMMXD:
       if (representation != _UVRSD_DOUBLE || regno > 31)
         return _UVRSR_FAILED;
       return unw_get_fpreg(cursor, (unw_regnum_t)(UNW_ARM_WR0 + regno),
                            (unw_fpreg_t *)valuep) == UNW_ESUCCESS
                  ? _UVRSR_OK
                  : _UVRSR_FAILED;
 #else

 /// function.
 _LIBUNWIND_EXPORT uintptr_t
 _Unwind_GetRegionStart(struct _Unwind_Context *context) {
   unw_cursor_t *cursor = (unw_cursor_t *)context;
   unw_proc_info_t frameInfo;
   uintptr_t result = 0;
   if (unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
     result = (uintptr_t)frameInfo.start_ip;
-  _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p) => 0x%llX",
-                       static_cast<void *>(context), (long long)result);
+  _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p) => 0x%" PRIX64 "",
+                       static_cast<void *>(context), result);
   return result;
 }
 
 
 /// Called by personality handler during phase 2 if a foreign exception
 // is caught.
 _LIBUNWIND_EXPORT void
 _Unwind_DeleteException(_Unwind_Exception *exception_object) {