[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

5 files changed, 97 insertions, 48 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