Generate minidumps for 64-bit ARM apps on iOS.

Adds an ARM64-specific definition of MDRawContext and support for writing out a
minidump when running on ARM64. Additionally, extends the iOS minidump generator
for NSExceptions to work on ARM64 as well as ARM.

Patch by Colin Blundell <blundell@chromium.org>

BUG=542

Review URL: https://breakpad.appspot.com/664002/


git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1235 4c0a9323-5329-0410-9bdc-e9ce6186880e

2 files changed, 70 insertions, 35 deletions

diff --git a/src/client/ios/handler/ios_exception_minidump_generator.h b/src/client/ios/handler/ios_exception_minidump_generator.h
index fd2f0149..21133e63 100644
--- a/src/client/ios/handler/ios_exception_minidump_generator.h
+++ b/src/client/ios/handler/ios_exception_minidump_generator.h
@@ -51,13 +51,20 @@ class IosExceptionMinidumpGenerator : public MinidumpGenerator {
  private:
 
   // Get the crashing program counter from the exception.
-  uint32_t GetPCFromException();
+  uintptr_t GetPCFromException();
 
   // Get the crashing link register from the exception.
-  uint32_t GetLRFromException();
+  uintptr_t GetLRFromException();
 
   // Write a virtual thread context for the crashing site.
   bool WriteCrashingContext(MDLocationDescriptor *register_location);
+  // Per-CPU implementations of the above method.
+#ifdef HAS_ARM_SUPPORT
+  bool WriteCrashingContextARM(MDLocationDescriptor *register_location);
+#endif
+#ifdef HAS_ARM64_SUPPORT
+  bool WriteCrashingContextARM64(MDLocationDescriptor *register_location);
+#endif
 
   NSArray *return_addresses_;
 };
diff --git a/src/client/ios/handler/ios_exception_minidump_generator.mm b/src/client/ios/handler/ios_exception_minidump_generator.mm
index 50bc3093..491c4916 100644
--- a/src/client/ios/handler/ios_exception_minidump_generator.mm
+++ b/src/client/ios/handler/ios_exception_minidump_generator.mm
@@ -31,25 +31,32 @@
 
 #include <pthread.h>
 
+#include "google_breakpad/common/minidump_cpu_arm.h"
+#include "google_breakpad/common/minidump_cpu_arm64.h"
 #include "google_breakpad/common/minidump_exception_mac.h"
 #include "client/minidump_file_writer-inl.h"
 #include "common/scoped_ptr.h"
 
+#if !defined(HAS_ARM_SUPPORT) && !defined(HAS_ARM64_SUPPORT)
+#error "This file should only be compiled for ARM processors"
+#endif
+
+#if defined(HAS_ARM_SUPPORT) && defined(HAS_ARM64_SUPPORT)
+#error "This file should be compiled for only one architecture at a time"
+#endif
+
 namespace {
 
-const uint32_t kExpectedFinalFp = 4;
-const uint32_t kExpectedFinalSp = 0;
+const uintptr_t kExpectedFinalFp = sizeof(uintptr_t);
+const uintptr_t kExpectedFinalSp = 0;
 const int kExceptionType = EXC_SOFTWARE;
 const int kExceptionCode = MD_EXCEPTION_CODE_MAC_NS_EXCEPTION;
 
-#ifdef HAS_ARM_SUPPORT
-// Append the given 4 bytes value to the sp position of the stack represented
+// Append the given value to the sp position of the stack represented
 // by memory.
-void AppendToMemory(uint8_t *memory, uint32_t sp, uint32_t data) {
-  assert(sizeof(data) == 4);
+void AppendToMemory(uint8_t *memory, uintptr_t sp, uintptr_t data) {
   memcpy(memory + sp, &data, sizeof(data));
 }
-#endif
 
 }  // namespace
 
@@ -72,6 +79,18 @@ IosExceptionMinidumpGenerator::~IosExceptionMinidumpGenerator() {
 bool IosExceptionMinidumpGenerator::WriteCrashingContext(
     MDLocationDescriptor *register_location) {
 #ifdef HAS_ARM_SUPPORT
+  return WriteCrashingContextARM(register_location);
+#elif defined(HAS_ARM64_SUPPORT)
+  return WriteCrashingContextARM64(register_location);
+#else
+#error "This file should only be compiled on ARM processors"
+  return false;
+#endif
+}
+
+#ifdef HAS_ARM_SUPPORT
+bool IosExceptionMinidumpGenerator::WriteCrashingContextARM(
+    MDLocationDescriptor *register_location) {
   TypedMDRVA<MDRawContextARM> context(&writer_);
   if (!context.Allocate())
     return false;
@@ -79,28 +98,42 @@ bool IosExceptionMinidumpGenerator::WriteCrashingContext(
   MDRawContextARM *context_ptr = context.get();
   memset(context_ptr, 0, sizeof(MDRawContextARM));
   context_ptr->context_flags = MD_CONTEXT_ARM_FULL;
-  context_ptr->iregs[7] = kExpectedFinalFp;  // FP
-  context_ptr->iregs[13] = kExpectedFinalSp;  // SP
-  context_ptr->iregs[14] = GetLRFromException();  // LR
-  context_ptr->iregs[15] = GetPCFromException();  // PC
+  context_ptr->iregs[MD_CONTEXT_ARM_REG_IOS_FP] = kExpectedFinalFp;  // FP
+  context_ptr->iregs[MD_CONTEXT_ARM_REG_SP] = kExpectedFinalSp;      // SP
+  context_ptr->iregs[MD_CONTEXT_ARM_REG_LR] = GetLRFromException();  // LR
+  context_ptr->iregs[MD_CONTEXT_ARM_REG_PC] = GetPCFromException();  // PC
   return true;
-#else
-  assert(false);
-  return false;
+}
 #endif
+
+#ifdef HAS_ARM64_SUPPORT
+bool IosExceptionMinidumpGenerator::WriteCrashingContextARM64(
+    MDLocationDescriptor *register_location) {
+  TypedMDRVA<MDRawContextARM64> context(&writer_);
+  if (!context.Allocate())
+    return false;
+  *register_location = context.location();
+  MDRawContextARM64 *context_ptr = context.get();
+  memset(context_ptr, 0, sizeof(*context_ptr));
+  context_ptr->context_flags = MD_CONTEXT_ARM64_FULL;
+  context_ptr->iregs[MD_CONTEXT_ARM64_REG_FP] = kExpectedFinalFp;      // FP
+  context_ptr->iregs[MD_CONTEXT_ARM64_REG_SP] = kExpectedFinalSp;      // SP
+  context_ptr->iregs[MD_CONTEXT_ARM64_REG_LR] = GetLRFromException();  // LR
+  context_ptr->iregs[MD_CONTEXT_ARM64_REG_PC] = GetPCFromException();  // PC
+  return true;
 }
+#endif
 
-uint32_t IosExceptionMinidumpGenerator::GetPCFromException() {
+uintptr_t IosExceptionMinidumpGenerator::GetPCFromException() {
   return [[return_addresses_ objectAtIndex:0] unsignedIntegerValue];
 }
 
-uint32_t IosExceptionMinidumpGenerator::GetLRFromException() {
+uintptr_t IosExceptionMinidumpGenerator::GetLRFromException() {
   return [[return_addresses_ objectAtIndex:1] unsignedIntegerValue];
 }
 
 bool IosExceptionMinidumpGenerator::WriteExceptionStream(
     MDRawDirectory *exception_stream) {
-#ifdef HAS_ARM_SUPPORT
   TypedMDRVA<MDRawExceptionStream> exception(&writer_);
 
   if (!exception.Allocate())
@@ -121,37 +154,35 @@ bool IosExceptionMinidumpGenerator::WriteExceptionStream(
 
   exception_ptr->exception_record.exception_address = GetPCFromException();
   return true;
-#else
-  return MinidumpGenerator::WriteExceptionStream(exception_stream);
-#endif
 }
 
 bool IosExceptionMinidumpGenerator::WriteThreadStream(mach_port_t thread_id,
                                                       MDRawThread *thread) {
-#ifdef HAS_ARM_SUPPORT
   if (pthread_mach_thread_np(pthread_self()) != thread_id)
     return MinidumpGenerator::WriteThreadStream(thread_id, thread);
 
   size_t frame_count = [return_addresses_ count];
   UntypedMDRVA memory(&writer_);
-  size_t size = 8 * (frame_count - 1) + 4;
-  if (!memory.Allocate(size))
+  size_t pointer_size = sizeof(uintptr_t);
+  size_t frame_record_size = 2 * pointer_size;
+  size_t stack_size = frame_record_size * (frame_count - 1) + pointer_size;
+  if (!memory.Allocate(stack_size))
     return false;
-  scoped_array<uint8_t> stack_memory(new uint8_t[size]);
-  uint32_t sp = size - 4;
-  uint32_t fp = 0;
-  uint32_t lr = 0;
+  scoped_array<uint8_t> stack_memory(new uint8_t[stack_size]);
+  uintptr_t sp = stack_size - pointer_size;
+  uintptr_t fp = 0;
+  uintptr_t lr = 0;
   for (int current_frame = frame_count - 1;
        current_frame > 0;
        --current_frame) {
     AppendToMemory(stack_memory.get(), sp, lr);
-    sp -= 4;
+    sp -= pointer_size;
     AppendToMemory(stack_memory.get(), sp, fp);
     fp = sp;
-    sp -= 4;
+    sp -= pointer_size;
     lr = [[return_addresses_ objectAtIndex:current_frame] unsignedIntegerValue];
   }
-  if (!memory.Copy(stack_memory.get(), size))
+  if (!memory.Copy(stack_memory.get(), stack_size))
     return false;
   assert(sp == kExpectedFinalSp);
   assert(fp == kExpectedFinalFp);
@@ -165,9 +196,6 @@ bool IosExceptionMinidumpGenerator::WriteThreadStream(mach_port_t thread_id,
 
   thread->thread_id = thread_id;
   return true;
-#else
-  return MinidumpGenerator::WriteThreadStream(thread_id, thread);
-#endif
 }
 
 }  // namespace google_breakpad