[MIPS]: Use mcontext_t structure for MIPS

This change removes user_regs_struct and
user_fpregs_struct structures for mips
and uses mcontext_t instead.

R=fdegans@chromium.org, mark@chromium.org, rmcilroy@chromium.org

Review URL: https://breakpad.appspot.com/3744002

Patch from Gordana Cmiljanovic <Gordana.Cmiljanovic@imgtec.com>.

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1452 4c0a9323-5329-0410-9bdc-e9ce6186880e

9 files changed, 134 insertions, 160 deletions

diff --git a/src/client/linux/dump_writer_common/thread_info.cc b/src/client/linux/dump_writer_common/thread_info.cc
index a3072b6c..9956d445 100644
--- a/src/client/linux/dump_writer_common/thread_info.cc
+++ b/src/client/linux/dump_writer_common/thread_info.cc
@@ -30,6 +30,7 @@
 #include "client/linux/dump_writer_common/thread_info.h"
 
 #include <string.h>
+#include <assert.h>
 
 #include "common/linux/linux_libc_support.h"
 #include "google_breakpad/common/minidump_format.h"
@@ -230,37 +231,69 @@ void ThreadInfo::FillCPUContext(RawContextCPU* out) const {
 #elif defined(__mips__)
 
 uintptr_t ThreadInfo::GetInstructionPointer() const {
-  return regs.epc;
+  return mcontext.pc;
 }
 
 void ThreadInfo::FillCPUContext(RawContextCPU* out) const {
   out->context_flags = MD_CONTEXT_MIPS_FULL;
 
   for (int i = 0; i < MD_CONTEXT_MIPS_GPR_COUNT; ++i)
-    out->iregs[i] = regs.regs[i];
+    out->iregs[i] = mcontext.gregs[i];
 
-  out->mdhi = regs.hi;
-  out->mdlo = regs.lo;
+  out->mdhi = mcontext.mdhi;
+  out->mdlo = mcontext.mdlo;
+  out->dsp_control = mcontext.dsp;
 
-  for (int i = 0; i < MD_CONTEXT_MIPS_DSP_COUNT; ++i) {
-    out->hi[i] = hi[i];
-    out->lo[i] = lo[i];
-  }
-  out->dsp_control = dsp_control;
+  out->hi[0] = mcontext.hi1;
+  out->lo[0] = mcontext.lo1;
+  out->hi[1] = mcontext.hi2;
+  out->lo[1] = mcontext.lo2;
+  out->hi[2] = mcontext.hi3;
+  out->lo[2] = mcontext.lo3;
 
-  out->epc = regs.epc;
-  out->badvaddr = regs.badvaddr;
-  out->status = regs.status;
-  out->cause = regs.cause;
+  out->epc = mcontext.pc;
+  out->badvaddr = 0; // Not stored in mcontext
+  out->status = 0; // Not stored in mcontext
+  out->cause = 0; // Not stored in mcontext
 
   for (int i = 0; i < MD_FLOATINGSAVEAREA_MIPS_FPR_COUNT; ++i)
-    out->float_save.regs[i] = fpregs.regs[i];
+    out->float_save.regs[i] = mcontext.fpregs.fp_r.fp_fregs[i]._fp_fregs;
 
-  out->float_save.fpcsr = fpregs.fpcsr;
+  out->float_save.fpcsr = mcontext.fpc_csr;
 #if _MIPS_SIM == _ABIO32
-  out->float_save.fir = fpregs.fir;
+  out->float_save.fir = mcontext.fpc_eir;
 #endif
 }
+#endif  // __mips__
+
+void ThreadInfo::GetGeneralPurposeRegisters(void** gp_regs, size_t* size) {
+  assert(gp_regs || size);
+#if defined(__mips__)
+  if (gp_regs)
+    *gp_regs = mcontext.gregs;
+  if (size)
+    *size = sizeof(mcontext.gregs);
+#else
+  if (gp_regs)
+    *gp_regs = &regs;
+  if (size)
+    *size = sizeof(regs);
 #endif
+}
+
+void ThreadInfo::GetFloatingPointRegisters(void** fp_regs, size_t* size) {
+  assert(fp_regs || size);
+#if defined(__mips__)
+  if (fp_regs)
+    *fp_regs = &mcontext.fpregs;
+  if (size)
+    *size = sizeof(mcontext.fpregs);
+#else
+  if (fp_regs)
+    *fp_regs = &fpregs;
+  if (size)
+    *size = sizeof(fpregs);
+#endif
+}
 
 }  // namespace google_breakpad
diff --git a/src/client/linux/dump_writer_common/thread_info.h b/src/client/linux/dump_writer_common/thread_info.h
index cf6d0101..a05ffea2 100644
--- a/src/client/linux/dump_writer_common/thread_info.h
+++ b/src/client/linux/dump_writer_common/thread_info.h
@@ -69,11 +69,8 @@ struct ThreadInfo {
   struct user_pt_regs regs;
   struct user_fpsimd_state fpregs;
 #elif defined(__mips__)
-  user_regs_struct regs;
-  user_fpregs_struct fpregs;
-  uint32_t hi[3];
-  uint32_t lo[3];
-  uint32_t dsp_control;
+  // Use the structure defined in <sys/ucontext.h>.
+  mcontext_t mcontext;
 #endif
 
   // Returns the instruction pointer (platform-dependent impl.).
@@ -81,6 +78,12 @@ struct ThreadInfo {
 
   // Fills a RawContextCPU using the context in the ThreadInfo object.
   void FillCPUContext(RawContextCPU* out) const;
+
+  // Returns the pointer and size of general purpose register area.
+  void GetGeneralPurposeRegisters(void** gp_regs, size_t* size);
+
+  // Returns the pointer and size of float point register area.
+  void GetFloatingPointRegisters(void** fp_regs, size_t* size);
 };
 
 }  // namespace google_breakpad
diff --git a/src/client/linux/minidump_writer/linux_core_dumper.cc b/src/client/linux/minidump_writer/linux_core_dumper.cc
index b8d90af6..d7328245 100644
--- a/src/client/linux/minidump_writer/linux_core_dumper.cc
+++ b/src/client/linux/minidump_writer/linux_core_dumper.cc
@@ -38,6 +38,10 @@
 #include <stdio.h>
 #include <string.h>
 #include <sys/procfs.h>
+#if defined(__mips__) && defined(__ANDROID__)
+// To get register definitions.
+#include <asm/reg.h>
+#endif
 
 #include "common/linux/linux_libc_support.h"
 
@@ -105,7 +109,7 @@ bool LinuxCoreDumper::GetThreadInfoByIndex(size_t index, ThreadInfo* info) {
   memcpy(&stack_pointer, &info->regs.sp, sizeof(info->regs.sp));
 #elif defined(__mips__)
   stack_pointer =
-      reinterpret_cast<uint8_t*>(info->regs.regs[MD_CONTEXT_MIPS_REG_SP]);
+      reinterpret_cast<uint8_t*>(info->mcontext.gregs[MD_CONTEXT_MIPS_REG_SP]);
 #else
 #error "This code hasn't been ported to your platform yet."
 #endif
@@ -191,18 +195,19 @@ bool LinuxCoreDumper::EnumerateThreads() {
         info.tgid = status->pr_pgrp;
         info.ppid = status->pr_ppid;
 #if defined(__mips__)
+#if defined(__ANDROID__)
+        for (int i = EF_R0; i <= EF_R31; i++)
+          info.mcontext.gregs[i - EF_R0] = status->pr_reg[i];
+#else  // __ANDROID__
         for (int i = EF_REG0; i <= EF_REG31; i++)
-          info.regs.regs[i - EF_REG0] = status->pr_reg[i];
-
-        info.regs.lo = status->pr_reg[EF_LO];
-        info.regs.hi = status->pr_reg[EF_HI];
-        info.regs.epc = status->pr_reg[EF_CP0_EPC];
-        info.regs.badvaddr = status->pr_reg[EF_CP0_BADVADDR];
-        info.regs.status = status->pr_reg[EF_CP0_STATUS];
-        info.regs.cause = status->pr_reg[EF_CP0_CAUSE];
-#else
+          info.mcontext.gregs[i - EF_REG0] = status->pr_reg[i];
+#endif  // __ANDROID__
+        info.mcontext.mdlo = status->pr_reg[EF_LO];
+        info.mcontext.mdhi = status->pr_reg[EF_HI];
+        info.mcontext.pc = status->pr_reg[EF_CP0_EPC];
+#else  // __mips__
         memcpy(&info.regs, status->pr_reg, sizeof(info.regs));
-#endif
+#endif  // __mips__
         if (first_thread) {
           crash_thread_ = pid;
           crash_signal_ = status->pr_info.si_signo;
diff --git a/src/client/linux/minidump_writer/linux_ptrace_dumper.cc b/src/client/linux/minidump_writer/linux_ptrace_dumper.cc
index 7a2cfb9f..5ea0050d 100644
--- a/src/client/linux/minidump_writer/linux_ptrace_dumper.cc
+++ b/src/client/linux/minidump_writer/linux_ptrace_dumper.cc
@@ -190,23 +190,25 @@ bool LinuxPtraceDumper::GetThreadInfoByIndex(size_t index, ThreadInfo* info) {
 
 #ifdef PTRACE_GETREGSET
   struct iovec io;
-  io.iov_base = &info->regs;
-  io.iov_len = sizeof(info->regs);
+  info->GetGeneralPurposeRegisters(&io.iov_base, &io.iov_len);
   if (sys_ptrace(PTRACE_GETREGSET, tid, (void*)NT_PRSTATUS, (void*)&io) == -1) {
     return false;
   }
 
-  io.iov_base = &info->fpregs;
-  io.iov_len = sizeof(info->fpregs);
+  info->GetFloatingPointRegisters(&io.iov_base, &io.iov_len);
   if (sys_ptrace(PTRACE_GETREGSET, tid, (void*)NT_FPREGSET, (void*)&io) == -1) {
     return false;
   }
-#else
-  if (sys_ptrace(PTRACE_GETREGS, tid, NULL, &info->regs) == -1) {
+#else  // PTRACE_GETREGSET
+  void* gp_addr;
+  info->GetGeneralPurposeRegisters(&gp_addr, NULL);
+  if (sys_ptrace(PTRACE_GETREGS, tid, NULL, gp_addr) == -1) {
     return false;
   }
 
-  if (sys_ptrace(PTRACE_GETFPREGS, tid, NULL, &info->fpregs) == -1) {
+  void* fp_addr;
+  info->GetFloatingPointRegisters(&fp_addr, NULL);
+  if (sys_ptrace(PTRACE_GETFPREGS, tid, NULL, fp_addr) == -1) {
     return false;
   }
 #endif
@@ -241,14 +243,20 @@ bool LinuxPtraceDumper::GetThreadInfoByIndex(size_t index, ThreadInfo* info) {
 #endif
 
 #if defined(__mips__)
-  for (int i = 0; i < 3; ++i) {
-    sys_ptrace(PTRACE_PEEKUSER, tid,
-               reinterpret_cast<void*>(DSP_BASE + (i * 2)), &info->hi[i]);
-    sys_ptrace(PTRACE_PEEKUSER, tid,
-               reinterpret_cast<void*>(DSP_BASE + (i * 2) + 1), &info->lo[i]);
-  }
   sys_ptrace(PTRACE_PEEKUSER, tid,
-             reinterpret_cast<void*>(DSP_CONTROL), &info->dsp_control);
+             reinterpret_cast<void*>(DSP_BASE), &info->mcontext.hi1);
+  sys_ptrace(PTRACE_PEEKUSER, tid,
+             reinterpret_cast<void*>(DSP_BASE + 1), &info->mcontext.lo1);
+  sys_ptrace(PTRACE_PEEKUSER, tid,
+             reinterpret_cast<void*>(DSP_BASE + 2), &info->mcontext.hi2);
+  sys_ptrace(PTRACE_PEEKUSER, tid,
+             reinterpret_cast<void*>(DSP_BASE + 3), &info->mcontext.lo2);
+  sys_ptrace(PTRACE_PEEKUSER, tid,
+             reinterpret_cast<void*>(DSP_BASE + 4), &info->mcontext.hi3);
+  sys_ptrace(PTRACE_PEEKUSER, tid,
+             reinterpret_cast<void*>(DSP_BASE + 5), &info->mcontext.lo3);
+  sys_ptrace(PTRACE_PEEKUSER, tid,
+             reinterpret_cast<void*>(DSP_CONTROL), &info->mcontext.dsp);
 #endif
 
   const uint8_t* stack_pointer;
@@ -262,7 +270,7 @@ bool LinuxPtraceDumper::GetThreadInfoByIndex(size_t index, ThreadInfo* info) {
   my_memcpy(&stack_pointer, &info->regs.sp, sizeof(info->regs.sp));
 #elif defined(__mips__)
   stack_pointer =
-      reinterpret_cast<uint8_t*>(info->regs.regs[MD_CONTEXT_MIPS_REG_SP]);
+      reinterpret_cast<uint8_t*>(info->mcontext.gregs[MD_CONTEXT_MIPS_REG_SP]);
 #else
 #error "This code hasn't been ported to your platform yet."
 #endif
diff --git a/src/client/linux/minidump_writer/linux_ptrace_dumper_unittest.cc b/src/client/linux/minidump_writer/linux_ptrace_dumper_unittest.cc
index 010ec67c..838ea5f6 100644
--- a/src/client/linux/minidump_writer/linux_ptrace_dumper_unittest.cc
+++ b/src/client/linux/minidump_writer/linux_ptrace_dumper_unittest.cc
@@ -441,7 +441,7 @@ TEST(LinuxPtraceDumperTest, VerifyStackReadWithMultipleThreads) {
     pid_t* process_tid_location = (pid_t*)(one_thread.regs.rcx);
 #elif defined(__mips__)
     pid_t* process_tid_location =
-        reinterpret_cast<pid_t*>(one_thread.regs.regs[1]);
+        reinterpret_cast<pid_t*>(one_thread.mcontext.gregs[1]);
 #else
 #error This test has not been ported to this platform.
 #endif
diff --git a/src/common/android/include/sys/procfs.h b/src/common/android/include/sys/procfs.h
index bedae34a..27223ea3 100644
--- a/src/common/android/include/sys/procfs.h
+++ b/src/common/android/include/sys/procfs.h
@@ -38,6 +38,9 @@
 
 #include <asm/ptrace.h>
 #include <sys/cdefs.h>
+#if defined (__mips__)
+#include <sys/types.h>
+#endif
 #include <sys/user.h>
 #include <unistd.h>
 
diff --git a/src/common/android/include/sys/user.h b/src/common/android/include/sys/user.h
index 05b22ced..24a0243a 100644
--- a/src/common/android/include/sys/user.h
+++ b/src/common/android/include/sys/user.h
@@ -33,88 +33,12 @@
 // The purpose of this file is to glue the mismatching headers (Android NDK vs
 // glibc) and therefore avoid doing otherwise awkward #ifdefs in the code.
 // The following quirks are currently handled by this file:
-// - MIPS: Keep using forked definitions of user.h structs. The definition in
-//     the NDK is completely different. Internal bug b/18097715
 // - i386: Use the Android NDK but alias user_fxsr_struct > user_fpxregs_struct.
 // - x86_64: Override a typo in user_fpregs_struct (mxcsr_mask -> mxcr_mask).
 //     The typo has been fixed in NDK r10d, but a preprocessor workaround is
 //     required to make breakpad build with r10c and lower (more details below).
 // - Other platforms: Just use the Android NDK unchanged.
 
-#ifdef __mips__
-#ifdef __cplusplus
-extern "C" {
-#endif  // __cplusplus
-
-#define EF_REG0 6
-#define EF_REG1 7
-#define EF_REG2 8
-#define EF_REG3 9
-#define EF_REG4 10
-#define EF_REG5 11
-#define EF_REG6 12
-#define EF_REG7 13
-#define EF_REG8 14
-#define EF_REG9 15
-#define EF_REG10 16
-#define EF_REG11 17
-#define EF_REG12 18
-#define EF_REG13 19
-#define EF_REG14 20
-#define EF_REG15 21
-#define EF_REG16 22
-#define EF_REG17 23
-#define EF_REG18 24
-#define EF_REG19 25
-#define EF_REG20 26
-#define EF_REG21 27
-#define EF_REG22 28
-#define EF_REG23 29
-#define EF_REG24 30
-#define EF_REG25 31
-
-/*
- * k0/k1 unsaved
- */
-#define EF_REG26 32
-#define EF_REG27 33
-#define EF_REG28 34
-#define EF_REG29 35
-#define EF_REG30 36
-#define EF_REG31 37
-
-/*
- * Saved special registers
- */
-#define EF_LO 38
-#define EF_HI 39
-#define EF_CP0_EPC 40
-#define EF_CP0_BADVADDR 41
-#define EF_CP0_STATUS 42
-#define EF_CP0_CAUSE 43
-
-struct user_regs_struct {
-  unsigned long long regs[32];
-  unsigned long long lo;
-  unsigned long long hi;
-  unsigned long long epc;
-  unsigned long long badvaddr;
-  unsigned long long status;
-  unsigned long long cause;
-};
-
-struct user_fpregs_struct {
-  unsigned long long regs[32];
-  unsigned int fpcsr;
-  unsigned int fir;
-};
-
-#ifdef __cplusplus
-}  // extern "C"
-#endif  // __cplusplus
-
-#else  //  __mips__
-
 // TODO(primiano): remove this after Chromium has stably rolled to NDK r10d.
 // Historical context: NDK releases < r10d had a typo in sys/user.h (mxcsr_mask
 // instead of mxcr_mask), which is fixed in r10d. However, just switching to use
@@ -143,6 +67,4 @@ typedef struct user_fxsr_struct user_fpxregs_struct;
 #endif  // __cplusplus
 #endif  // __i386__
 
-#endif  // __mips__
-
 #endif  // GOOGLE_BREAKPAD_COMMON_ANDROID_INCLUDE_SYS_USER_H
diff --git a/src/google_breakpad/common/minidump_cpu_mips.h b/src/google_breakpad/common/minidump_cpu_mips.h
index 4378aac2..6cbe3023 100644
--- a/src/google_breakpad/common/minidump_cpu_mips.h
+++ b/src/google_breakpad/common/minidump_cpu_mips.h
@@ -66,24 +66,6 @@
 #ifndef GOOGLE_BREAKPAD_COMMON_MINIDUMP_CPU_MIPS_H__
 #define GOOGLE_BREAKPAD_COMMON_MINIDUMP_CPU_MIPS_H__
 
-#if defined(__mips__) && !defined(__ANDROID__)
-typedef struct {
-  uint64_t regs[32];
-  uint64_t lo;
-  uint64_t hi;
-  uint64_t epc;
-  uint64_t badvaddr;
-  uint64_t status;
-  uint64_t cause;
-} user_regs_struct;
-
-typedef struct {
-  uint64_t regs[32];
-  uint32_t fpcsr;
-  uint32_t fir;
-} user_fpregs_struct;
-#endif
-
 #define MD_CONTEXT_MIPS_GPR_COUNT 32
 #define MD_FLOATINGSAVEAREA_MIPS_FPR_COUNT 32
 #define MD_CONTEXT_MIPS_DSP_COUNT 3
@@ -112,8 +94,8 @@ typedef struct {
 
   /* 32 64-bit integer registers, r0..r31.
    * Note the following fixed uses:
-   *   r30 is the stack pointer.
-   *   r31 is the return address (link register).
+   *   r29 is the stack pointer.
+   *   r31 is the return address.
    */
   uint64_t iregs[MD_CONTEXT_MIPS_GPR_COUNT];
 
diff --git a/src/tools/linux/md2core/minidump-2-core.cc b/src/tools/linux/md2core/minidump-2-core.cc
index bcb0076e..21d410bc 100644
--- a/src/tools/linux/md2core/minidump-2-core.cc
+++ b/src/tools/linux/md2core/minidump-2-core.cc
@@ -81,6 +81,9 @@
 // containing core registers, while they use 'user_regs_struct' on other
 // architectures. This file-local typedef simplifies the source code.
 typedef user_regs user_regs_struct;
+#elif defined (__mips__)
+// This file-local typedef simplifies the source code.
+typedef gregset_t user_regs_struct;
 #endif
 
 using google_breakpad::MDTypeHelper;
@@ -208,13 +211,17 @@ struct CrashedProcess {
 
   struct Thread {
     pid_t tid;
+#if defined(__mips__)
+    mcontext_t mcontext;
+#else  // __mips__
     user_regs_struct regs;
-#if defined(__i386__) || defined(__x86_64__) || defined(__mips__)
+#if defined(__i386__) || defined(__x86_64__)
     user_fpregs_struct fpregs;
-#endif
+#endif  // __i386__ || __x86_64__
 #if defined(__i386__)
     user_fpxregs_struct fpxregs;
-#endif
+#endif  // __i386__
+#endif  // __mips__
     uintptr_t stack_addr;
     const uint8_t* stack;
     size_t stack_length;
@@ -371,21 +378,28 @@ ParseThreadRegisters(CrashedProcess::Thread* thread,
   const MDRawContextMIPS* rawregs = range.GetData<MDRawContextMIPS>(0);
 
   for (int i = 0; i < MD_CONTEXT_MIPS_GPR_COUNT; ++i)
-    thread->regs.regs[i] = rawregs->iregs[i];
+    thread->mcontext.gregs[i] = rawregs->iregs[i];
+
+  thread->mcontext.pc = rawregs->epc;
 
-  thread->regs.lo = rawregs->mdlo;
-  thread->regs.hi = rawregs->mdhi;
-  thread->regs.epc = rawregs->epc;
-  thread->regs.badvaddr = rawregs->badvaddr;
-  thread->regs.status = rawregs->status;
-  thread->regs.cause = rawregs->cause;
+  thread->mcontext.mdlo = rawregs->mdlo;
+  thread->mcontext.mdhi = rawregs->mdhi;
 
-  for (int i = 0; i < MD_FLOATINGSAVEAREA_MIPS_FPR_COUNT; ++i)
-    thread->fpregs.regs[i] = rawregs->float_save.regs[i];
+  thread->mcontext.hi1 = rawregs->hi[0];
+  thread->mcontext.lo1 = rawregs->lo[0];
+  thread->mcontext.hi2 = rawregs->hi[1];
+  thread->mcontext.lo2 = rawregs->lo[1];
+  thread->mcontext.hi3 = rawregs->hi[2];
+  thread->mcontext.lo3 = rawregs->lo[2];
 
-  thread->fpregs.fpcsr = rawregs->float_save.fpcsr;
+  for (int i = 0; i < MD_FLOATINGSAVEAREA_MIPS_FPR_COUNT; ++i) {
+    thread->mcontext.fpregs.fp_r.fp_fregs[i]._fp_fregs =
+        rawregs->float_save.regs[i];
+  }
+
+  thread->mcontext.fpc_csr = rawregs->float_save.fpcsr;
 #if _MIPS_SIM == _ABIO32
-  thread->fpregs.fir = rawregs->float_save.fir;
+  thread->mcontext.fpc_eir = rawregs->float_save.fir;
 #endif
 }
 #else
@@ -751,7 +765,11 @@ WriteThread(const CrashedProcess::Thread& thread, int fatal_signal) {
   pr.pr_info.si_signo = fatal_signal;
   pr.pr_cursig = fatal_signal;
   pr.pr_pid = thread.tid;
+#if defined(__mips__)
+  memcpy(&pr.pr_reg, &thread.mcontext.gregs, sizeof(user_regs_struct));
+#else
   memcpy(&pr.pr_reg, &thread.regs, sizeof(user_regs_struct));
+#endif
 
   Nhdr nhdr;
   memset(&nhdr, 0, sizeof(nhdr));