Issue 196 - Breakpad processor support for x86-64. r=mento

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@227 4c0a9323-5329-0410-9bdc-e9ce6186880e

11 files changed, 818 insertions, 201 deletions

diff --git a/Makefile.am b/Makefile.am
index 2edfd94e..f6e331d1 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -93,6 +93,8 @@ src_libbreakpad_la_SOURCES = \
 	src/processor/simple_symbol_supplier.h \
 	src/processor/stack_frame_info.h \
 	src/processor/stackwalker.cc \
+	src/processor/stackwalker_amd64.cc \
+	src/processor/stackwalker_amd64.h \
 	src/processor/stackwalker_ppc.cc \
 	src/processor/stackwalker_ppc.h \
 	src/processor/stackwalker_sparc.cc \
@@ -161,6 +163,7 @@ src_processor_minidump_processor_unittest_LDADD = \
 	src/processor/pathname_stripper.lo \
 	src/processor/process_state.lo \
 	src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
 	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
@@ -192,6 +195,7 @@ src_processor_stackwalker_selftest_LDADD = \
 	src/processor/minidump.lo \
 	src/processor/pathname_stripper.lo \
 	src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
 	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
@@ -221,6 +225,7 @@ src_processor_minidump_stackwalk_LDADD = \
 	src/processor/process_state.lo \
 	src/processor/simple_symbol_supplier.lo \
 	src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
 	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
diff --git a/Makefile.in b/Makefile.in
index f4a81182..a7ec92ae 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -112,7 +112,9 @@ am_src_libbreakpad_la_OBJECTS = src/processor/basic_code_modules.lo \
 	src/processor/pathname_stripper.lo \
 	src/processor/process_state.lo \
 	src/processor/simple_symbol_supplier.lo \
-	src/processor/stackwalker.lo src/processor/stackwalker_ppc.lo \
+	src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
+	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
 src_libbreakpad_la_OBJECTS = $(am_src_libbreakpad_la_OBJECTS)
@@ -156,6 +158,7 @@ src_processor_minidump_processor_unittest_DEPENDENCIES =  \
 	src/processor/minidump_processor.lo src/processor/minidump.lo \
 	src/processor/pathname_stripper.lo \
 	src/processor/process_state.lo src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
 	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
@@ -171,7 +174,9 @@ src_processor_minidump_stackwalk_DEPENDENCIES =  \
 	src/processor/pathname_stripper.lo \
 	src/processor/process_state.lo \
 	src/processor/simple_symbol_supplier.lo \
-	src/processor/stackwalker.lo src/processor/stackwalker_ppc.lo \
+	src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
+	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
 am_src_processor_pathname_stripper_unittest_OBJECTS =  \
@@ -201,7 +206,9 @@ src_processor_stackwalker_selftest_DEPENDENCIES =  \
 	src/processor/basic_source_line_resolver.lo \
 	src/processor/call_stack.lo src/processor/logging.lo \
 	src/processor/minidump.lo src/processor/pathname_stripper.lo \
-	src/processor/stackwalker.lo src/processor/stackwalker_ppc.lo \
+	src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
+	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
 SCRIPTS = $(noinst_SCRIPTS)
@@ -425,6 +432,8 @@ src_libbreakpad_la_SOURCES = \
 	src/processor/simple_symbol_supplier.h \
 	src/processor/stack_frame_info.h \
 	src/processor/stackwalker.cc \
+	src/processor/stackwalker_amd64.cc \
+	src/processor/stackwalker_amd64.h \
 	src/processor/stackwalker_ppc.cc \
 	src/processor/stackwalker_ppc.h \
 	src/processor/stackwalker_sparc.cc \
@@ -474,6 +483,7 @@ src_processor_minidump_processor_unittest_LDADD = \
 	src/processor/pathname_stripper.lo \
 	src/processor/process_state.lo \
 	src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
 	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
@@ -509,6 +519,7 @@ src_processor_stackwalker_selftest_LDADD = \
 	src/processor/minidump.lo \
 	src/processor/pathname_stripper.lo \
 	src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
 	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
@@ -537,6 +548,7 @@ src_processor_minidump_stackwalk_LDADD = \
 	src/processor/process_state.lo \
 	src/processor/simple_symbol_supplier.lo \
 	src/processor/stackwalker.lo \
+	src/processor/stackwalker_amd64.lo \
 	src/processor/stackwalker_ppc.lo \
 	src/processor/stackwalker_sparc.lo \
 	src/processor/stackwalker_x86.lo
@@ -781,6 +793,8 @@ src/processor/simple_symbol_supplier.lo:  \
 	src/processor/$(DEPDIR)/$(am__dirstamp)
 src/processor/stackwalker.lo: src/processor/$(am__dirstamp) \
 	src/processor/$(DEPDIR)/$(am__dirstamp)
+src/processor/stackwalker_amd64.lo: src/processor/$(am__dirstamp) \
+	src/processor/$(DEPDIR)/$(am__dirstamp)
 src/processor/stackwalker_ppc.lo: src/processor/$(am__dirstamp) \
 	src/processor/$(DEPDIR)/$(am__dirstamp)
 src/processor/stackwalker_sparc.lo: src/processor/$(am__dirstamp) \
@@ -925,6 +939,8 @@ mostlyclean-compile:
 	-rm -f src/processor/simple_symbol_supplier.lo
 	-rm -f src/processor/stackwalker.$(OBJEXT)
 	-rm -f src/processor/stackwalker.lo
+	-rm -f src/processor/stackwalker_amd64.$(OBJEXT)
+	-rm -f src/processor/stackwalker_amd64.lo
 	-rm -f src/processor/stackwalker_ppc.$(OBJEXT)
 	-rm -f src/processor/stackwalker_ppc.lo
 	-rm -f src/processor/stackwalker_selftest.$(OBJEXT)
@@ -955,6 +971,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@src/processor/$(DEPDIR)/range_map_unittest.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@src/processor/$(DEPDIR)/simple_symbol_supplier.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@src/processor/$(DEPDIR)/stackwalker.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@src/processor/$(DEPDIR)/stackwalker_amd64.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@src/processor/$(DEPDIR)/stackwalker_ppc.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@src/processor/$(DEPDIR)/stackwalker_selftest.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@src/processor/$(DEPDIR)/stackwalker_sparc.Plo@am__quote@
diff --git a/src/google_breakpad/common/minidump_format.h b/src/google_breakpad/common/minidump_format.h
index cb6811e0..229bb9b2 100644
--- a/src/google_breakpad/common/minidump_format.h
+++ b/src/google_breakpad/common/minidump_format.h
@@ -216,6 +216,160 @@ typedef struct {
 #define MD_CONTEXT_CPU_MASK 0xffffffc0
 
 /*
+ * AMD64 support, see WINNT.H
+ */
+
+typedef struct {
+  u_int16_t  control_word;
+  u_int16_t  status_word;
+  u_int8_t   tag_word;
+  u_int8_t   reserved1;
+  u_int16_t  error_opcode;
+  u_int32_t  error_offset;
+  u_int16_t  error_selector;
+  u_int16_t  reserved2;
+  u_int32_t  data_offset;
+  u_int16_t  data_selector;
+  u_int16_t  reserved3;
+  u_int32_t  mx_csr;
+  u_int32_t  mx_csr_mask;
+  u_int128_t float_registers[8];
+  u_int128_t xmm_registers[16];
+  u_int8_t   reserved4[96];
+} MDXmmSaveArea32AMD64;  /* XMM_SAVE_AREA32 */
+
+#define MD_CONTEXT_AMD64_VR_COUNT 26
+
+typedef struct {
+  /*
+   * Register parameter home addresses.
+   */
+  u_int64_t  p1_home;
+  u_int64_t  p2_home;
+  u_int64_t  p3_home;
+  u_int64_t  p4_home;
+  u_int64_t  p5_home;
+  u_int64_t  p6_home;
+
+  /* The next field determines the layout of the structure, and which parts
+   * of it are populated */
+  u_int32_t  context_flags;
+  u_int32_t  mx_csr;
+
+  /* The next register is included with MD_CONTEXT_AMD64_CONTROL */
+  u_int16_t  cs;
+
+  /* The next 4 registers are included with MD_CONTEXT_AMD64_SEGMENTS */
+  u_int16_t  ds;
+  u_int16_t  es;
+  u_int16_t  fs;
+  u_int16_t  gs;
+
+  /* The next 2 registers are included with MD_CONTEXT_AMD64_CONTROL */
+  u_int16_t  ss;
+  u_int32_t  eflags;
+  
+  /* The next 6 registers are included with MD_CONTEXT_AMD64_DEBUG_REGISTERS */
+  u_int64_t  dr0;
+  u_int64_t  dr1;
+  u_int64_t  dr2;
+  u_int64_t  dr3;
+  u_int64_t  dr6;
+  u_int64_t  dr7;
+
+  /* The next 4 registers are included with MD_CONTEXT_AMD64_INTEGER */
+  u_int64_t  rax;
+  u_int64_t  rcx;
+  u_int64_t  rdx;
+  u_int64_t  rbx;
+
+  /* The next register is included with MD_CONTEXT_AMD64_CONTROL */
+  u_int64_t  rsp;
+
+  /* The next 11 registers are included with MD_CONTEXT_AMD64_INTEGER */
+  u_int64_t  rbp;
+  u_int64_t  rsi;
+  u_int64_t  rdi;
+  u_int64_t  r8;
+  u_int64_t  r9;
+  u_int64_t  r10;
+  u_int64_t  r11;
+  u_int64_t  r12;
+  u_int64_t  r13;
+  u_int64_t  r14;
+  u_int64_t  r15;
+
+  /* The next register is included with MD_CONTEXT_AMD64_CONTROL */
+  u_int64_t  rip;
+
+  /* The next set of registers are included with
+   * MD_CONTEXT_AMD64_FLOATING_POINT
+   */
+  union {
+    MDXmmSaveArea32AMD64 flt_save;
+    struct {
+      u_int128_t header[2];
+      u_int128_t legacy[8];
+      u_int128_t xmm0;
+      u_int128_t xmm1;
+      u_int128_t xmm2;
+      u_int128_t xmm3;
+      u_int128_t xmm4;
+      u_int128_t xmm5;
+      u_int128_t xmm6;
+      u_int128_t xmm7;
+      u_int128_t xmm8;
+      u_int128_t xmm9;
+      u_int128_t xmm10;
+      u_int128_t xmm11;
+      u_int128_t xmm12;
+      u_int128_t xmm13;
+      u_int128_t xmm14;
+      u_int128_t xmm15;
+    } sse_registers;
+  };
+
+  u_int128_t vector_register[MD_CONTEXT_AMD64_VR_COUNT];
+  u_int64_t  vector_control;
+
+  /* The next 5 registers are included with MD_CONTEXT_AMD64_DEBUG_REGISTERS */
+  u_int64_t debug_control;
+  u_int64_t last_branch_to_rip;
+  u_int64_t last_branch_from_rip;
+  u_int64_t last_exception_to_rip;
+  u_int64_t last_exception_from_rip;
+  
+} MDRawContextAMD64;  /* CONTEXT */
+
+/* For (MDRawContextAMD64).context_flags.  These values indicate the type of
+ * context stored in the structure.  The high 26 bits identify the CPU, the
+ * low 6 bits identify the type of context saved. */
+#define MD_CONTEXT_AMD64_CONTROL         (MD_CONTEXT_AMD64 | 0x00000001)
+     /* CONTEXT_CONTROL */
+#define MD_CONTEXT_AMD64_INTEGER         (MD_CONTEXT_AMD64 | 0x00000002)
+     /* CONTEXT_INTEGER */
+#define MD_CONTEXT_AMD64_SEGMENTS        (MD_CONTEXT_AMD64 | 0x00000004)
+     /* CONTEXT_SEGMENTS */
+#define MD_CONTEXT_AMD64_FLOATING_POINT  (MD_CONTEXT_AMD64 | 0x00000008)
+     /* CONTEXT_FLOATING_POINT */
+#define MD_CONTEXT_AMD64_DEBUG_REGISTERS (MD_CONTEXT_AMD64 | 0x00000010)
+     /* CONTEXT_DEBUG_REGISTERS */
+/* WinNT.h refers to CONTEXT_MMX_REGISTERS but doesn't appear to define it
+ * I think it really means CONTEXT_FLOATING_POINT.
+ */
+
+#define MD_CONTEXT_AMD64_FULL            (MD_CONTEXT_AMD64_CONTROL | \
+                                          MD_CONTEXT_AMD64_INTEGER | \
+                                          MD_CONTEXT_AMD64_FLOATING_POINT)
+     /* CONTEXT_FULL */
+
+#define MD_CONTEXT_AMD64_ALL             (MD_CONTEXT_AMD64_FULL | \
+                                          MD_CONTEXT_AMD64_SEGMENTS | \
+                                          MD_CONTEXT_X86_DEBUG_REGISTERS)
+     /* CONTEXT_ALL */
+
+
+/*
  * SPARC support, see (solaris)sys/procfs_isa.h also
  */
 
diff --git a/src/google_breakpad/processor/minidump.h b/src/google_breakpad/processor/minidump.h
index 474382b9..4e900fb1 100644
--- a/src/google_breakpad/processor/minidump.h
+++ b/src/google_breakpad/processor/minidump.h
@@ -175,8 +175,9 @@ class MinidumpContext : public MinidumpStream {
   // Returns raw CPU-specific context data for the named CPU type.  If the
   // context data does not match the CPU type or does not exist, returns
   // NULL.
-  const MDRawContextX86* GetContextX86() const;
-  const MDRawContextPPC* GetContextPPC() const;
+  const MDRawContextX86*   GetContextX86() const;
+  const MDRawContextPPC*   GetContextPPC() const;
+  const MDRawContextAMD64* GetContextAMD64() const;
   const MDRawContextSPARC* GetContextSPARC() const;
  
   // Print a human-readable representation of the object to stdout.
@@ -200,11 +201,15 @@ class MinidumpContext : public MinidumpStream {
   // not contain a system info stream.
   bool CheckAgainstSystemInfo(u_int32_t context_cpu_type);
 
+  // Store this separately because of the weirdo AMD64 context
+  u_int32_t context_flags_;
+
   // The CPU-specific context structure.
   union {
-    MDRawContextBase* base;
-    MDRawContextX86*  x86;
-    MDRawContextPPC*  ppc;
+    MDRawContextBase*  base;
+    MDRawContextX86*   x86;
+    MDRawContextPPC*   ppc;
+    MDRawContextAMD64* amd64;
     // on Solaris SPARC, sparc is defined as a numeric constant,
     // so variables can NOT be named as sparc
     MDRawContextSPARC*  ctx_sparc;
diff --git a/src/google_breakpad/processor/stack_frame_cpu.h b/src/google_breakpad/processor/stack_frame_cpu.h
index 567c1b7e..a8840278 100644
--- a/src/google_breakpad/processor/stack_frame_cpu.h
+++ b/src/google_breakpad/processor/stack_frame_cpu.h
@@ -98,6 +98,32 @@ struct StackFramePPC : public StackFrame {
   int context_validity;
 };
 
+struct StackFrameAMD64 : public StackFrame {
+  // ContextValidity has one entry for each relevant hardware pointer register
+  // (%rip and %rsp) and one entry for each nonvolatile (callee-save) register.
+  //FIXME: validate this list
+  enum ContextValidity {
+    CONTEXT_VALID_NONE = 0,
+    CONTEXT_VALID_RIP  = 1 << 0,
+    CONTEXT_VALID_RSP  = 1 << 1,
+    CONTEXT_VALID_RBP  = 1 << 2,
+    CONTEXT_VALID_ALL  = -1
+  };
+
+  StackFrameAMD64() : context(), context_validity(CONTEXT_VALID_NONE) {}
+
+  // Register state.  This is only fully valid for the topmost frame in a
+  // stack.  In other frames, the values of nonvolatile registers may be
+  // present, given sufficient debugging information.  Refer to
+  // context_validity.
+  MDRawContextAMD64 context;
+
+  // context_validity is actually ContextValidity, but int is used because
+  // the OR operator doesn't work well with enumerated types.  This indicates
+  // which fields in context are valid.
+  int context_validity;
+};
+
 struct StackFrameSPARC : public StackFrame {
   // to be confirmed
   enum ContextValidity {
diff --git a/src/processor/minidump.cc b/src/processor/minidump.cc
index 3cce5ed7..d08ad12f 100644
--- a/src/processor/minidump.cc
+++ b/src/processor/minidump.cc
@@ -271,6 +271,7 @@ MinidumpStream::MinidumpStream(Minidump* minidump)
 
 MinidumpContext::MinidumpContext(Minidump* minidump)
     : MinidumpStream(minidump),
+      context_flags_(0),
       context_() {
 }
 
@@ -286,233 +287,334 @@ bool MinidumpContext::Read(u_int32_t expected_size) {
   FreeContext();
 
   // First, figure out what type of CPU this context structure is for.
-  u_int32_t context_flags;
-  if (!minidump_->ReadBytes(&context_flags, sizeof(context_flags))) {
-    BPLOG(ERROR) << "MinidumpContext could not read context flags";
-    return false;
-  }
-  if (minidump_->swap())
-    Swap(&context_flags);
+  // For some reason, the AMD64 Context doesn't have context_flags
+  // at the beginning of the structure, so special case it here.
+  if (expected_size == sizeof(MDRawContextAMD64)) {
+    BPLOG(INFO) << "MinidumpContext: looks like AMD64 context";
+
+    scoped_ptr<MDRawContextAMD64> context_amd64(new MDRawContextAMD64());
+    if (!minidump_->ReadBytes(context_amd64.get(),
+                              sizeof(MDRawContextAMD64))) {
+      BPLOG(ERROR) << "MinidumpContext could not read amd64 context";
+      return false;
+    }
 
-  u_int32_t cpu_type = context_flags & MD_CONTEXT_CPU_MASK;
+    if (minidump_->swap())
+      Swap(&context_amd64->context_flags);
 
-  // Allocate the context structure for the correct CPU and fill it.  The
-  // casts are slightly unorthodox, but it seems better to do that than to
-  // maintain a separate pointer for each type of CPU context structure
-  // when only one of them will be used.
-  switch (cpu_type) {
-    case MD_CONTEXT_X86: {
-      if (expected_size != sizeof(MDRawContextX86)) {
-        BPLOG(ERROR) << "MinidumpContext x86 size mismatch, " <<
-                        expected_size << " != " << sizeof(MDRawContextX86);
-        return false;
-      }
+    u_int32_t cpu_type = context_amd64->context_flags & MD_CONTEXT_CPU_MASK;
 
-      scoped_ptr<MDRawContextX86> context_x86(new MDRawContextX86());
+    if (cpu_type != MD_CONTEXT_AMD64) {
+      //TODO: fall through to switch below?
+      // need a Tell method to be able to SeekSet back to beginning
+      // http://code.google.com/p/google-breakpad/issues/detail?id=224
+      BPLOG(ERROR) << "MinidumpContext not actually amd64 context";
+      return false;
+    }
 
-      // Set the context_flags member, which has already been read, and
-      // read the rest of the structure beginning with the first member
-      // after context_flags.
-      context_x86->context_flags = context_flags;
+    // Do this after reading the entire MDRawContext structure because
+    // GetSystemInfo may seek minidump to a new position.
+    if (!CheckAgainstSystemInfo(cpu_type)) {
+      BPLOG(ERROR) << "MinidumpContext amd64 does not match system info";
+      return false;
+    }
 
-      size_t flags_size = sizeof(context_x86->context_flags);
-      u_int8_t* context_after_flags =
-          reinterpret_cast<u_int8_t*>(context_x86.get()) + flags_size;
-      if (!minidump_->ReadBytes(context_after_flags,
-                                sizeof(MDRawContextX86) - flags_size)) {
-        BPLOG(ERROR) << "MinidumpContext could not read x86 context";
-        return false;
-      }
+    // Normalize the 128-bit types in the dump.
+    // Since this is AMD64, by definition, the values are little-endian.
+    for (unsigned int vr_index = 0;
+         vr_index < MD_CONTEXT_AMD64_VR_COUNT;
+         ++vr_index)
+      Normalize128(&context_amd64->vector_register[vr_index], false);
 
-      // Do this after reading the entire MDRawContext structure because
-      // GetSystemInfo may seek minidump to a new position.
-      if (!CheckAgainstSystemInfo(cpu_type)) {
-        BPLOG(ERROR) << "MinidumpContext x86 does not match system info";
-        return false;
-      }
+    if (minidump_->swap()) {
+      Swap(&context_amd64->p1_home);
+      Swap(&context_amd64->p2_home);
+      Swap(&context_amd64->p3_home);
+      Swap(&context_amd64->p4_home);
+      Swap(&context_amd64->p5_home);
+      Swap(&context_amd64->p6_home);
+      // context_flags is already swapped
+      Swap(&context_amd64->mx_csr);
+      Swap(&context_amd64->cs);
+      Swap(&context_amd64->ds);
+      Swap(&context_amd64->es);
+      Swap(&context_amd64->fs);
+      Swap(&context_amd64->ss);
+      Swap(&context_amd64->eflags);
+      Swap(&context_amd64->dr0);
+      Swap(&context_amd64->dr1);
+      Swap(&context_amd64->dr2);
+      Swap(&context_amd64->dr3);
+      Swap(&context_amd64->dr6);
+      Swap(&context_amd64->dr7);
+      Swap(&context_amd64->rax);
+      Swap(&context_amd64->rcx);
+      Swap(&context_amd64->rdx);
+      Swap(&context_amd64->rbx);
+      Swap(&context_amd64->rsp);
+      Swap(&context_amd64->rbp);
+      Swap(&context_amd64->rsi);
+      Swap(&context_amd64->rdi);
+      Swap(&context_amd64->r8);
+      Swap(&context_amd64->r9);
+      Swap(&context_amd64->r10);
+      Swap(&context_amd64->r11);
+      Swap(&context_amd64->r12);
+      Swap(&context_amd64->r13);
+      Swap(&context_amd64->r14);
+      Swap(&context_amd64->r15);
+      Swap(&context_amd64->rip);
+      //FIXME: I'm not sure what actually determines
+      // which member of the union {flt_save, sse_registers}
+      // is valid.  We're not currently using either,
+      // but it would be good to have them swapped properly.
 
-      if (minidump_->swap()) {
-        // context_x86->context_flags was already swapped.
-        Swap(&context_x86->dr0);
-        Swap(&context_x86->dr1);
-        Swap(&context_x86->dr2);
-        Swap(&context_x86->dr3);
-        Swap(&context_x86->dr6);
-        Swap(&context_x86->dr7);
-        Swap(&context_x86->float_save.control_word);
-        Swap(&context_x86->float_save.status_word);
-        Swap(&context_x86->float_save.tag_word);
-        Swap(&context_x86->float_save.error_offset);
-        Swap(&context_x86->float_save.error_selector);
-        Swap(&context_x86->float_save.data_offset);
-        Swap(&context_x86->float_save.data_selector);
-        // context_x86->float_save.register_area[] contains 8-bit quantities
-        // and does not need to be swapped.
-        Swap(&context_x86->float_save.cr0_npx_state);
-        Swap(&context_x86->gs);
-        Swap(&context_x86->fs);
-        Swap(&context_x86->es);
-        Swap(&context_x86->ds);
-        Swap(&context_x86->edi);
-        Swap(&context_x86->esi);
-        Swap(&context_x86->ebx);
-        Swap(&context_x86->edx);
-        Swap(&context_x86->ecx);
-        Swap(&context_x86->eax);
-        Swap(&context_x86->ebp);
-        Swap(&context_x86->eip);
-        Swap(&context_x86->cs);
-        Swap(&context_x86->eflags);
-        Swap(&context_x86->esp);
-        Swap(&context_x86->ss);
-        // context_x86->extended_registers[] contains 8-bit quantities and
-        // does not need to be swapped.
-      }
+      for (unsigned int vr_index = 0;
+           vr_index < MD_CONTEXT_AMD64_VR_COUNT;
+           ++vr_index)
+        Swap(&context_amd64->vector_register[vr_index]);
+      Swap(&context_amd64->vector_control);
+      Swap(&context_amd64->debug_control);
+      Swap(&context_amd64->last_branch_to_rip);
+      Swap(&context_amd64->last_branch_from_rip);
+      Swap(&context_amd64->last_exception_to_rip);
+      Swap(&context_amd64->last_exception_from_rip);
+    }
 
-      context_.x86 = context_x86.release();
+    context_flags_ = context_amd64->context_flags;
 
-      break;
+    context_.amd64 = context_amd64.release();
+  }
+  else {
+    u_int32_t context_flags;
+    if (!minidump_->ReadBytes(&context_flags, sizeof(context_flags))) {
+      BPLOG(ERROR) << "MinidumpContext could not read context flags";
+      return false;
     }
+    if (minidump_->swap())
+      Swap(&context_flags);
+
+    u_int32_t cpu_type = context_flags & MD_CONTEXT_CPU_MASK;
+
+    // Allocate the context structure for the correct CPU and fill it.  The
+    // casts are slightly unorthodox, but it seems better to do that than to
+    // maintain a separate pointer for each type of CPU context structure
+    // when only one of them will be used.
+    switch (cpu_type) {
+      case MD_CONTEXT_X86: {
+        if (expected_size != sizeof(MDRawContextX86)) {
+          BPLOG(ERROR) << "MinidumpContext x86 size mismatch, " <<
+            expected_size << " != " << sizeof(MDRawContextX86);
+          return false;
+        }
 
-    case MD_CONTEXT_PPC: {
-      if (expected_size != sizeof(MDRawContextPPC)) {
-        BPLOG(ERROR) << "MinidumpContext ppc size mismatch, " <<
-                        expected_size << " != " << sizeof(MDRawContextPPC);
-        return false;
-      }
+        scoped_ptr<MDRawContextX86> context_x86(new MDRawContextX86());
 
-      scoped_ptr<MDRawContextPPC> context_ppc(new MDRawContextPPC());
+        // Set the context_flags member, which has already been read, and
+        // read the rest of the structure beginning with the first member
+        // after context_flags.
+        context_x86->context_flags = context_flags;
 
-      // Set the context_flags member, which has already been read, and
-      // read the rest of the structure beginning with the first member
-      // after context_flags.
-      context_ppc->context_flags = context_flags;
+        size_t flags_size = sizeof(context_x86->context_flags);
+        u_int8_t* context_after_flags =
+          reinterpret_cast<u_int8_t*>(context_x86.get()) + flags_size;
+        if (!minidump_->ReadBytes(context_after_flags,
+                                  sizeof(MDRawContextX86) - flags_size)) {
+          BPLOG(ERROR) << "MinidumpContext could not read x86 context";
+          return false;
+        }
 
-      size_t flags_size = sizeof(context_ppc->context_flags);
-      u_int8_t* context_after_flags =
-          reinterpret_cast<u_int8_t*>(context_ppc.get()) + flags_size;
-      if (!minidump_->ReadBytes(context_after_flags,
-                                sizeof(MDRawContextPPC) - flags_size)) {
-        BPLOG(ERROR) << "MinidumpContext could not read ppc context";
-        return false;
-      }
+        // Do this after reading the entire MDRawContext structure because
+        // GetSystemInfo may seek minidump to a new position.
+        if (!CheckAgainstSystemInfo(cpu_type)) {
+          BPLOG(ERROR) << "MinidumpContext x86 does not match system info";
+          return false;
+        }
 
-      // Do this after reading the entire MDRawContext structure because
-      // GetSystemInfo may seek minidump to a new position.
-      if (!CheckAgainstSystemInfo(cpu_type)) {
-        BPLOG(ERROR) << "MinidumpContext ppc does not match system info";
-        return false;
-      }
+        if (minidump_->swap()) {
+          // context_x86->context_flags was already swapped.
+          Swap(&context_x86->dr0);
+          Swap(&context_x86->dr1);
+          Swap(&context_x86->dr2);
+          Swap(&context_x86->dr3);
+          Swap(&context_x86->dr6);
+          Swap(&context_x86->dr7);
+          Swap(&context_x86->float_save.control_word);
+          Swap(&context_x86->float_save.status_word);
+          Swap(&context_x86->float_save.tag_word);
+          Swap(&context_x86->float_save.error_offset);
+          Swap(&context_x86->float_save.error_selector);
+          Swap(&context_x86->float_save.data_offset);
+          Swap(&context_x86->float_save.data_selector);
+          // context_x86->float_save.register_area[] contains 8-bit quantities
+          // and does not need to be swapped.
+          Swap(&context_x86->float_save.cr0_npx_state);
+          Swap(&context_x86->gs);
+          Swap(&context_x86->fs);
+          Swap(&context_x86->es);
+          Swap(&context_x86->ds);
+          Swap(&context_x86->edi);
+          Swap(&context_x86->esi);
+          Swap(&context_x86->ebx);
+          Swap(&context_x86->edx);
+          Swap(&context_x86->ecx);
+          Swap(&context_x86->eax);
+          Swap(&context_x86->ebp);
+          Swap(&context_x86->eip);
+          Swap(&context_x86->cs);
+          Swap(&context_x86->eflags);
+          Swap(&context_x86->esp);
+          Swap(&context_x86->ss);
+          // context_x86->extended_registers[] contains 8-bit quantities and
+          // does not need to be swapped.
+        }
 
-      // Normalize the 128-bit types in the dump.
-      // Since this is PowerPC, by definition, the values are big-endian.
-      for (unsigned int vr_index = 0;
-           vr_index < MD_VECTORSAVEAREA_PPC_VR_COUNT;
-           ++vr_index) {
-        Normalize128(&context_ppc->vector_save.save_vr[vr_index], true);
+        context_.x86 = context_x86.release();
+
+        break;
       }
 
-      if (minidump_->swap()) {
-        // context_ppc->context_flags was already swapped.
-        Swap(&context_ppc->srr0);
-        Swap(&context_ppc->srr1);
-        for (unsigned int gpr_index = 0;
-             gpr_index < MD_CONTEXT_PPC_GPR_COUNT;
-             ++gpr_index) {
-          Swap(&context_ppc->gpr[gpr_index]);
+      case MD_CONTEXT_PPC: {
+        if (expected_size != sizeof(MDRawContextPPC)) {
+          BPLOG(ERROR) << "MinidumpContext ppc size mismatch, " <<
+            expected_size << " != " << sizeof(MDRawContextPPC);
+          return false;
+        }
+
+        scoped_ptr<MDRawContextPPC> context_ppc(new MDRawContextPPC());
+
+        // Set the context_flags member, which has already been read, and
+        // read the rest of the structure beginning with the first member
+        // after context_flags.
+        context_ppc->context_flags = context_flags;
+
+        size_t flags_size = sizeof(context_ppc->context_flags);
+        u_int8_t* context_after_flags =
+          reinterpret_cast<u_int8_t*>(context_ppc.get()) + flags_size;
+        if (!minidump_->ReadBytes(context_after_flags,
+                                  sizeof(MDRawContextPPC) - flags_size)) {
+          BPLOG(ERROR) << "MinidumpContext could not read ppc context";
+          return false;
         }
-        Swap(&context_ppc->cr);
-        Swap(&context_ppc->xer);
-        Swap(&context_ppc->lr);
-        Swap(&context_ppc->ctr);
-        Swap(&context_ppc->mq);
-        Swap(&context_ppc->vrsave);
-        for (unsigned int fpr_index = 0;
-             fpr_index < MD_FLOATINGSAVEAREA_PPC_FPR_COUNT;
-             ++fpr_index) {
-          Swap(&context_ppc->float_save.fpregs[fpr_index]);
+
+        // Do this after reading the entire MDRawContext structure because
+        // GetSystemInfo may seek minidump to a new position.
+        if (!CheckAgainstSystemInfo(cpu_type)) {
+          BPLOG(ERROR) << "MinidumpContext ppc does not match system info";
+          return false;
         }
-        // Don't swap context_ppc->float_save.fpscr_pad because it is only
-        // used for padding.
-        Swap(&context_ppc->float_save.fpscr);
+
+        // Normalize the 128-bit types in the dump.
+        // Since this is PowerPC, by definition, the values are big-endian.
         for (unsigned int vr_index = 0;
              vr_index < MD_VECTORSAVEAREA_PPC_VR_COUNT;
              ++vr_index) {
-          Swap(&context_ppc->vector_save.save_vr[vr_index]);
+          Normalize128(&context_ppc->vector_save.save_vr[vr_index], true);
         }
-        Swap(&context_ppc->vector_save.save_vscr);
-        // Don't swap the padding fields in vector_save.
-        Swap(&context_ppc->vector_save.save_vrvalid);
-      }
 
-      context_.ppc = context_ppc.release();
+        if (minidump_->swap()) {
+          // context_ppc->context_flags was already swapped.
+          Swap(&context_ppc->srr0);
+          Swap(&context_ppc->srr1);
+          for (unsigned int gpr_index = 0;
+               gpr_index < MD_CONTEXT_PPC_GPR_COUNT;
+               ++gpr_index) {
+            Swap(&context_ppc->gpr[gpr_index]);
+          }
+          Swap(&context_ppc->cr);
+          Swap(&context_ppc->xer);
+          Swap(&context_ppc->lr);
+          Swap(&context_ppc->ctr);
+          Swap(&context_ppc->mq);
+          Swap(&context_ppc->vrsave);
+          for (unsigned int fpr_index = 0;
+               fpr_index < MD_FLOATINGSAVEAREA_PPC_FPR_COUNT;
+               ++fpr_index) {
+            Swap(&context_ppc->float_save.fpregs[fpr_index]);
+          }
+          // Don't swap context_ppc->float_save.fpscr_pad because it is only
+          // used for padding.
+          Swap(&context_ppc->float_save.fpscr);
+          for (unsigned int vr_index = 0;
+               vr_index < MD_VECTORSAVEAREA_PPC_VR_COUNT;
+               ++vr_index) {
+            Swap(&context_ppc->vector_save.save_vr[vr_index]);
+          }
+          Swap(&context_ppc->vector_save.save_vscr);
+          // Don't swap the padding fields in vector_save.
+          Swap(&context_ppc->vector_save.save_vrvalid);
+        }
 
-      break;
-    }
+        context_.ppc = context_ppc.release();
 
-    case MD_CONTEXT_SPARC: {
-      if (expected_size != sizeof(MDRawContextSPARC)) {
-        BPLOG(ERROR) << "MinidumpContext sparc size mismatch, " <<
-                        expected_size << " != " << sizeof(MDRawContextSPARC);
-        return false;
+        break;
       }
 
-      scoped_ptr<MDRawContextSPARC> context_sparc(new MDRawContextSPARC());
+      case MD_CONTEXT_SPARC: {
+        if (expected_size != sizeof(MDRawContextSPARC)) {
+          BPLOG(ERROR) << "MinidumpContext sparc size mismatch, " <<
+            expected_size << " != " << sizeof(MDRawContextSPARC);
+          return false;
+        }
 
-      // Set the context_flags member, which has already been read, and
-      // read the rest of the structure beginning with the first member
-      // after context_flags.
-      context_sparc->context_flags = context_flags;
+        scoped_ptr<MDRawContextSPARC> context_sparc(new MDRawContextSPARC());
 
-      size_t flags_size = sizeof(context_sparc->context_flags);
-      u_int8_t* context_after_flags =
-          reinterpret_cast<u_int8_t*>(context_sparc.get()) + flags_size;
-      if (!minidump_->ReadBytes(context_after_flags,
-                                sizeof(MDRawContextSPARC) - flags_size)) {
-        BPLOG(ERROR) << "MinidumpContext could not read sparc context";
-        return false;
-      }
+        // Set the context_flags member, which has already been read, and
+        // read the rest of the structure beginning with the first member
+        // after context_flags.
+        context_sparc->context_flags = context_flags;
 
-      // Do this after reading the entire MDRawContext structure because
-      // GetSystemInfo may seek minidump to a new position.
-      if (!CheckAgainstSystemInfo(cpu_type)) {
-        BPLOG(ERROR) << "MinidumpContext sparc does not match system info";
-        return false;
-      }
+        size_t flags_size = sizeof(context_sparc->context_flags);
+        u_int8_t* context_after_flags =
+            reinterpret_cast<u_int8_t*>(context_sparc.get()) + flags_size;
+        if (!minidump_->ReadBytes(context_after_flags,
+                                  sizeof(MDRawContextSPARC) - flags_size)) {
+          BPLOG(ERROR) << "MinidumpContext could not read sparc context";
+          return false;
+        }
 
-      if (minidump_->swap()) {
-        // context_sparc->context_flags was already swapped.
-        for (unsigned int gpr_index = 0;
-             gpr_index < MD_CONTEXT_SPARC_GPR_COUNT;
-             ++gpr_index) {
-          Swap(&context_sparc->g_r[gpr_index]);
+        // Do this after reading the entire MDRawContext structure because
+        // GetSystemInfo may seek minidump to a new position.
+        if (!CheckAgainstSystemInfo(cpu_type)) {
+          BPLOG(ERROR) << "MinidumpContext sparc does not match system info";
+          return false;
         }
-        Swap(&context_sparc->ccr);
-        Swap(&context_sparc->pc);
-        Swap(&context_sparc->npc);
-        Swap(&context_sparc->y);
-        Swap(&context_sparc->asi);
-        Swap(&context_sparc->fprs);
-        for (unsigned int fpr_index = 0;
-             fpr_index < MD_FLOATINGSAVEAREA_SPARC_FPR_COUNT;
-             ++fpr_index) {
-          Swap(&context_sparc->float_save.regs[fpr_index]);
+
+        if (minidump_->swap()) {
+          // context_sparc->context_flags was already swapped.
+          for (unsigned int gpr_index = 0;
+               gpr_index < MD_CONTEXT_SPARC_GPR_COUNT;
+               ++gpr_index) {
+            Swap(&context_sparc->g_r[gpr_index]);
+          }
+          Swap(&context_sparc->ccr);
+          Swap(&context_sparc->pc);
+          Swap(&context_sparc->npc);
+          Swap(&context_sparc->y);
+          Swap(&context_sparc->asi);
+          Swap(&context_sparc->fprs);
+          for (unsigned int fpr_index = 0;
+               fpr_index < MD_FLOATINGSAVEAREA_SPARC_FPR_COUNT;
+               ++fpr_index) {
+            Swap(&context_sparc->float_save.regs[fpr_index]);
+          }
+          Swap(&context_sparc->float_save.filler);
+          Swap(&context_sparc->float_save.fsr);
         }
-        Swap(&context_sparc->float_save.filler);
-        Swap(&context_sparc->float_save.fsr);
-      }
-      context_.ctx_sparc = context_sparc.release();
+        context_.ctx_sparc = context_sparc.release();
 
-      break;
-    }
+        break;
+      }
 
-    default: {
-      // Unknown context type
-      BPLOG(ERROR) << "MinidumpContext unknown context type " <<
-                      HexString(cpu_type);
-      return false;
-      break;
+      default: {
+        // Unknown context type
+        BPLOG(ERROR) << "MinidumpContext unknown context type " <<
+          HexString(cpu_type);
+        return false;
+        break;
+      }
     }
+    context_flags_ = context_flags;
   }
 
   valid_ = true;
@@ -527,7 +629,7 @@ u_int32_t MinidumpContext::GetContextCPU() const {
     return 0;
   }
 
-  return context_.base->context_flags & MD_CONTEXT_CPU_MASK;
+  return context_flags_ & MD_CONTEXT_CPU_MASK;
 }
 
 
@@ -550,6 +652,15 @@ const MDRawContextPPC* MinidumpContext::GetContextPPC() const {
   return context_.ppc;
 }
 
+const MDRawContextAMD64* MinidumpContext::GetContextAMD64() const {
+  if (GetContextCPU() != MD_CONTEXT_AMD64) {
+    BPLOG(ERROR) << "MinidumpContext cannot get amd64 context";
+    return NULL;
+  }
+
+  return context_.amd64;
+}
+
 const MDRawContextSPARC* MinidumpContext::GetContextSPARC() const {
   if (GetContextCPU() != MD_CONTEXT_SPARC) {
     BPLOG(ERROR) << "MinidumpContext cannot get sparc context";
@@ -569,6 +680,10 @@ void MinidumpContext::FreeContext() {
       delete context_.ppc;
       break;
 
+    case MD_CONTEXT_AMD64:
+      delete context_.amd64;
+      break;
+
     case MD_CONTEXT_SPARC:
       delete context_.ctx_sparc;
       break;
@@ -580,6 +695,7 @@ void MinidumpContext::FreeContext() {
       break;
   }
 
+  context_flags_ = 0;
   context_.base = NULL;
 }
 
@@ -621,6 +737,11 @@ bool MinidumpContext::CheckAgainstSystemInfo(u_int32_t context_cpu_type) {
         return_value = true;
       break;
 
+    case MD_CONTEXT_AMD64:
+      if (system_info_cpu_type == MD_CPU_ARCHITECTURE_AMD64)
+        return_value = true;
+      break;
+
     case MD_CONTEXT_SPARC:
       if (system_info_cpu_type == MD_CPU_ARCHITECTURE_SPARC)
         return_value = true;
@@ -745,6 +866,60 @@ void MinidumpContext::Print() {
       break;
     }
 
+    case MD_CONTEXT_AMD64: {
+      const MDRawContextAMD64* context_amd64 = GetContextAMD64();
+      printf("MDRawContextAMD64\n");
+      printf("  p1_home       = 0x%llx\n",
+             context_amd64->p1_home);
+      printf("  p2_home       = 0x%llx\n",
+             context_amd64->p2_home);
+      printf("  p3_home       = 0x%llx\n",
+             context_amd64->p3_home);
+      printf("  p4_home       = 0x%llx\n",
+             context_amd64->p4_home);
+      printf("  p5_home       = 0x%llx\n",
+             context_amd64->p5_home);
+      printf("  p6_home       = 0x%llx\n",
+             context_amd64->p6_home);
+      printf("  context_flags = 0x%x\n",
+             context_amd64->context_flags);
+      printf("  mx_csr        = 0x%x\n",
+             context_amd64->mx_csr);
+      printf("  cs            = 0x%x\n", context_amd64->cs);
+      printf("  ds            = 0x%x\n", context_amd64->ds);
+      printf("  es            = 0x%x\n", context_amd64->es);
+      printf("  fs            = 0x%x\n", context_amd64->fs);
+      printf("  gs            = 0x%x\n", context_amd64->gs);
+      printf("  ss            = 0x%x\n", context_amd64->ss);
+      printf("  eflags        = 0x%x\n", context_amd64->eflags);
+      printf("  dr0           = 0x%llx\n", context_amd64->dr0);
+      printf("  dr1           = 0x%llx\n", context_amd64->dr1);
+      printf("  dr2           = 0x%llx\n", context_amd64->dr2);
+      printf("  dr3           = 0x%llx\n", context_amd64->dr3);
+      printf("  dr6           = 0x%llx\n", context_amd64->dr6);
+      printf("  dr7           = 0x%llx\n", context_amd64->dr7);
+      printf("  rax           = 0x%llx\n", context_amd64->rax);
+      printf("  rcx           = 0x%llx\n", context_amd64->rcx);
+      printf("  rdx           = 0x%llx\n", context_amd64->rdx);
+      printf("  rbx           = 0x%llx\n", context_amd64->rbx);
+      printf("  rsp           = 0x%llx\n", context_amd64->rsp);
+      printf("  rbp           = 0x%llx\n", context_amd64->rbp);
+      printf("  rsi           = 0x%llx\n", context_amd64->rsi);
+      printf("  rdi           = 0x%llx\n", context_amd64->rdi);
+      printf("  r8            = 0x%llx\n", context_amd64->r8);
+      printf("  r9            = 0x%llx\n", context_amd64->r9);
+      printf("  r10           = 0x%llx\n", context_amd64->r10);
+      printf("  r11           = 0x%llx\n", context_amd64->r11);
+      printf("  r12           = 0x%llx\n", context_amd64->r12);
+      printf("  r13           = 0x%llx\n", context_amd64->r13);
+      printf("  r14           = 0x%llx\n", context_amd64->r14);
+      printf("  r15           = 0x%llx\n", context_amd64->r15);
+      printf("  rip           = 0x%llx\n", context_amd64->rip);
+      //TODO: print xmm, vector, debug registers
+      printf("\n");
+      break;
+    }
+
     case MD_CONTEXT_SPARC: {
       const MDRawContextSPARC* context_sparc = GetContextSPARC();
       printf("MDRawContextSPARC\n");
diff --git a/src/processor/minidump_processor.cc b/src/processor/minidump_processor.cc
index 54e6b545..3c609170 100644
--- a/src/processor/minidump_processor.cc
+++ b/src/processor/minidump_processor.cc
@@ -258,8 +258,14 @@ bool MinidumpProcessor::GetCPUInfo(Minidump *dump, SystemInfo *info) {
     return false;
 
   switch (raw_system_info->processor_architecture) {
-    case MD_CPU_ARCHITECTURE_X86: {
-      info->cpu = "x86";
+    case MD_CPU_ARCHITECTURE_X86:
+    case MD_CPU_ARCHITECTURE_AMD64: {
+      if (raw_system_info->processor_architecture == 
+          MD_CPU_ARCHITECTURE_X86)
+        info->cpu = "x86";
+      else
+        info->cpu = "amd64";
+
       const string *cpu_vendor = system_info->GetCPUVendor();
       if (cpu_vendor) {
         info->cpu_info = *cpu_vendor;
diff --git a/src/processor/minidump_stackwalk.cc b/src/processor/minidump_stackwalk.cc
index 547914db..785d6512 100644
--- a/src/processor/minidump_stackwalk.cc
+++ b/src/processor/minidump_stackwalk.cc
@@ -68,6 +68,7 @@ using google_breakpad::StackFrame;
 using google_breakpad::StackFramePPC;
 using google_breakpad::StackFrameSPARC;
 using google_breakpad::StackFrameX86;
+using google_breakpad::StackFrameAMD64;
 
 // Separator character for machine readable output.
 static const char kOutputSeparator = '|';
@@ -165,6 +166,16 @@ static void PrintStack(const CallStack *stack, const string &cpu) {
         sequence = PrintRegister("srr0", frame_ppc->context.srr0, sequence);
       if (frame_ppc->context_validity & StackFramePPC::CONTEXT_VALID_GPR1)
         sequence = PrintRegister("r1", frame_ppc->context.gpr[1], sequence);
+    } else if (cpu == "amd64") {
+      const StackFrameAMD64 *frame_amd64 =
+        reinterpret_cast<const StackFrameAMD64*>(frame);
+
+      if (frame_amd64->context_validity & StackFrameAMD64::CONTEXT_VALID_RIP)
+        sequence = PrintRegister("rip", frame_amd64->context.rip, sequence);
+      if (frame_amd64->context_validity & StackFrameAMD64::CONTEXT_VALID_RSP)
+        sequence = PrintRegister("rsp", frame_amd64->context.rsp, sequence);
+      if (frame_amd64->context_validity & StackFrameAMD64::CONTEXT_VALID_RBP)
+        sequence = PrintRegister("rbp", frame_amd64->context.rbp, sequence);
     } else if (cpu == "sparc") {
       const StackFrameSPARC *frame_sparc =
           reinterpret_cast<const StackFrameSPARC*>(frame);
@@ -176,7 +187,6 @@ static void PrintStack(const CallStack *stack, const string &cpu) {
       if (frame_sparc->context_validity & StackFrameSPARC::CONTEXT_VALID_PC)
         sequence = PrintRegister("pc", frame_sparc->context.pc, sequence);
     }
-
     printf("\n");
   }
 }
diff --git a/src/processor/stackwalker.cc b/src/processor/stackwalker.cc
index 502f07d4..cdb0ce52 100644
--- a/src/processor/stackwalker.cc
+++ b/src/processor/stackwalker.cc
@@ -51,6 +51,7 @@
 #include "processor/stackwalker_ppc.h"
 #include "processor/stackwalker_sparc.h"
 #include "processor/stackwalker_x86.h"
+#include "processor/stackwalker_amd64.h"
 
 namespace google_breakpad {
 
@@ -164,6 +165,13 @@ Stackwalker* Stackwalker::StackwalkerForCPU(
                                            memory, modules, supplier,
                                            resolver);
       break;
+
+    case MD_CONTEXT_AMD64:
+      cpu_stackwalker = new StackwalkerAMD64(system_info,
+                                             context->GetContextAMD64(),
+                                             memory, modules, supplier,
+                                             resolver);
+      break;
   
     case MD_CONTEXT_SPARC:
       cpu_stackwalker = new StackwalkerSPARC(system_info,
diff --git a/src/processor/stackwalker_amd64.cc b/src/processor/stackwalker_amd64.cc
new file mode 100644
index 00000000..7a413963
--- /dev/null
+++ b/src/processor/stackwalker_amd64.cc
@@ -0,0 +1,131 @@
+// Copyright (c) 2007, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// stackwalker_amd64.cc: amd64-specific stackwalker.
+//
+// See stackwalker_amd64.h for documentation.
+//
+// Author: Mark Mentovai, Ted Mielczarek
+
+
+#include "processor/stackwalker_amd64.h"
+#include "google_breakpad/processor/call_stack.h"
+#include "google_breakpad/processor/memory_region.h"
+#include "google_breakpad/processor/stack_frame_cpu.h"
+#include "processor/logging.h"
+
+namespace google_breakpad {
+
+
+StackwalkerAMD64::StackwalkerAMD64(const SystemInfo *system_info,
+                                   const MDRawContextAMD64 *context,
+                                   MemoryRegion *memory,
+                                   const CodeModules *modules,
+                                   SymbolSupplier *supplier,
+                                   SourceLineResolverInterface *resolver)
+    : Stackwalker(system_info, memory, modules, supplier, resolver),
+      context_(context) {
+}
+
+
+StackFrame* StackwalkerAMD64::GetContextFrame() {
+  if (!context_ || !memory_) {
+    BPLOG(ERROR) << "Can't get context frame without context or memory";
+    return NULL;
+  }
+
+  StackFrameAMD64 *frame = new StackFrameAMD64();
+
+  // The instruction pointer is stored directly in a register, so pull it
+  // straight out of the CPU context structure.
+  frame->context = *context_;
+  frame->context_validity = StackFrameAMD64::CONTEXT_VALID_ALL;
+  frame->instruction = frame->context.rip;
+
+  return frame;
+}
+
+
+StackFrame* StackwalkerAMD64::GetCallerFrame(
+    const CallStack *stack,
+    const vector< linked_ptr<StackFrameInfo> > &stack_frame_info) {
+  if (!memory_ || !stack) {
+    BPLOG(ERROR) << "Can't get caller frame without memory or stack";
+    return NULL;
+  }
+
+  StackFrameAMD64 *last_frame = static_cast<StackFrameAMD64*>(
+      stack->frames()->back());
+
+  //FIXME: this pretty much doesn't work at all due to FPO
+  // being enabled by default.
+  // Brain-dead stackwalking:
+  // %rip_new = *(%rbp_old + 8)
+  // %rsp_new = %rbp_old + 16
+  // %rbp_new = *(%rbp_old)
+
+  // A caller frame must reside higher in memory than its callee frames.
+  // Anything else is an error, or an indication that we've reached the
+  // end of the stack.
+  u_int64_t stack_pointer = last_frame->context.rbp + 16;
+  if (stack_pointer <= last_frame->context.rsp) {
+    return NULL;
+  }
+
+  u_int64_t instruction;
+  if (!memory_->GetMemoryAtAddress(last_frame->context.rbp + 8,
+                                   &instruction) ||
+      instruction <= 1) {
+    return NULL;
+  }
+
+  u_int64_t stack_base;
+  if (!memory_->GetMemoryAtAddress(last_frame->context.rbp,
+                                   &stack_base) ||
+      stack_base <= 1) {
+    return NULL;
+  }
+
+  StackFrameAMD64 *frame = new StackFrameAMD64();
+
+  frame->context = last_frame->context;
+  frame->context.rip = instruction;
+  frame->context.rsp = stack_pointer;
+  frame->context.rbp = stack_base;
+  frame->context_validity = StackFrameAMD64::CONTEXT_VALID_RIP |
+                            StackFrameAMD64::CONTEXT_VALID_RSP |
+                            StackFrameAMD64::CONTEXT_VALID_RBP;
+
+  frame->instruction = frame->context.rip - 1;
+
+  return frame;
+}
+
+
+}  // namespace google_breakpad
diff --git a/src/processor/stackwalker_amd64.h b/src/processor/stackwalker_amd64.h
new file mode 100644
index 00000000..a3e11358
--- /dev/null
+++ b/src/processor/stackwalker_amd64.h
@@ -0,0 +1,80 @@
+// Copyright (c) 2007, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// stackwalker_amd64.h: amd64-specific stackwalker.
+//
+// Provides stack frames given amd64 register context and a memory region
+// corresponding to a amd64 stack.
+//
+// Author: Mark Mentovai, Ted Mielczarek
+
+
+#ifndef PROCESSOR_STACKWALKER_AMD64_H__
+#define PROCESSOR_STACKWALKER_AMD64_H__
+
+
+#include "google_breakpad/common/breakpad_types.h"
+#include "google_breakpad/common/minidump_format.h"
+#include "google_breakpad/processor/stackwalker.h"
+
+namespace google_breakpad {
+
+class CodeModules;
+
+class StackwalkerAMD64 : public Stackwalker {
+ public:
+  // context is a amd64 context object that gives access to amd64-specific
+  // register state corresponding to the innermost called frame to be
+  // included in the stack.  The other arguments are passed directly through
+  // to the base Stackwalker constructor.
+  StackwalkerAMD64(const SystemInfo *system_info,
+                   const MDRawContextAMD64 *context,
+                   MemoryRegion *memory,
+                   const CodeModules *modules,
+                   SymbolSupplier *supplier,
+                   SourceLineResolverInterface *resolver);
+
+ private:
+  // Implementation of Stackwalker, using amd64 context (stack pointer in %rsp,
+  // stack base in %rbp) and stack conventions (saved stack pointer at 0(%rbp))
+  virtual StackFrame* GetContextFrame();
+  virtual StackFrame* GetCallerFrame(
+      const CallStack *stack,
+      const vector< linked_ptr<StackFrameInfo> > &stack_frame_info);
+
+  // Stores the CPU context corresponding to the innermost stack frame to
+  // be returned by GetContextFrame.
+  const MDRawContextAMD64 *context_;
+};
+
+
+}  // namespace google_breakpad
+
+
+#endif  // PROCESSOR_STACKWALKER_AMD64_H__