From 46de5800031b08fb31042f43f9cd6c49cec891d3 Mon Sep 17 00:00:00 2001
From: Kostya Serebryany <kcc@google.com>
Date: Tue, 20 Nov 2012 07:00:42 +0000
Subject: [PATCH] [asan] more support for powerpc, patch by Peter Bergner

llvm-svn: 168356
---
 compiler-rt/lib/asan/asan_linux.cc                       |  9 ++++++++-
 compiler-rt/lib/asan/asan_mapping.h                      | 10 +++++++++-
 compiler-rt/lib/sanitizer_common/sanitizer_common.h      | 15 ++++++++++++++-
 compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.cc | 13 +++++++++++++
 compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.h  |  2 ++
 5 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/compiler-rt/lib/asan/asan_linux.cc b/compiler-rt/lib/asan/asan_linux.cc
index 1f46f26..740bf5e 100644
--- a/compiler-rt/lib/asan/asan_linux.cc
+++ b/compiler-rt/lib/asan/asan_linux.cc
@@ -68,6 +68,13 @@ void GetPcSpBp(void *context, uptr *pc, uptr *sp, uptr *bp) {
   *pc = ucontext->uc_mcontext.gregs[REG_EIP];
   *bp = ucontext->uc_mcontext.gregs[REG_EBP];
   *sp = ucontext->uc_mcontext.gregs[REG_ESP];
+# elif defined(__powerpc__) || defined(__powerpc64__)
+  ucontext_t *ucontext = (ucontext_t*)context;
+  *pc = ucontext->uc_mcontext.regs->nip;
+  *sp = ucontext->uc_mcontext.regs->gpr[PT_R1];
+  // The powerpc{,64}-linux ABIs do not specify r31 as the frame
+  // pointer, but GCC always uses r31 when we need a frame pointer.
+  *bp = ucontext->uc_mcontext.regs->gpr[PT_R31];
 # elif defined(__sparc__)
   ucontext_t *ucontext = (ucontext_t*)context;
   uptr *stk_ptr;
@@ -151,7 +158,7 @@ void GetStackTrace(StackTrace *stack, uptr max_s, uptr pc, uptr bp) {
   stack->trace[0] = pc;
   if ((max_s) > 1) {
     stack->max_size = max_s;
-#ifdef __arm__
+#if defined(__arm__) || defined(__powerpc__) || defined(__powerpc64__)
     _Unwind_Backtrace(Unwind_Trace, stack);
 #else
     if (!asan_inited) return;
diff --git a/compiler-rt/lib/asan/asan_mapping.h b/compiler-rt/lib/asan/asan_mapping.h
index 40e3220..8480bcf 100644
--- a/compiler-rt/lib/asan/asan_mapping.h
+++ b/compiler-rt/lib/asan/asan_mapping.h
@@ -33,7 +33,11 @@ extern __attribute__((visibility("default"))) uptr __asan_mapping_offset;
 #  if __WORDSIZE == 32
 #   define SHADOW_OFFSET (1 << 29)
 #  else
-#   define SHADOW_OFFSET (1ULL << 44)
+#   if defined(__powerpc64__)
+#    define SHADOW_OFFSET (1ULL << 41)
+#   else
+#    define SHADOW_OFFSET (1ULL << 44)
+#   endif
 #  endif
 # endif
 #endif  // ASAN_FLEXIBLE_MAPPING_AND_OFFSET
@@ -43,7 +47,11 @@ extern __attribute__((visibility("default"))) uptr __asan_mapping_offset;
 #define SHADOW_TO_MEM(shadow) (((shadow) - SHADOW_OFFSET) << SHADOW_SCALE)
 
 #if __WORDSIZE == 64
+# if defined(__powerpc64__)
+  static const uptr kHighMemEnd = 0x00000fffffffffffUL;
+# else
   static const uptr kHighMemEnd = 0x00007fffffffffffUL;
+# endif
 #else  // __WORDSIZE == 32
   static const uptr kHighMemEnd = 0xffffffff;
 #endif  // __WORDSIZE
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common.h b/compiler-rt/lib/sanitizer_common/sanitizer_common.h
index 27cc308..0a98012 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common.h
@@ -23,12 +23,25 @@ namespace __sanitizer {
 // Constants.
 const uptr kWordSize = __WORDSIZE / 8;
 const uptr kWordSizeInBits = 8 * kWordSize;
+#if defined(__powerpc__) || defined(__powerpc64__)
+// Current PPC64 kernels use 64K pages sizes, but they can be
+// configured with 4K or even other sizes.
+// We may want to use getpagesize() or sysconf(_SC_PAGESIZE) here rather than
+// hardcoding the values, but today these values need to be compile-time
+// constants.
+const uptr kPageSizeBits = 16;
+const uptr kPageSize = 1UL << kPageSizeBits;
+const uptr kCacheLineSize = 128;
+const uptr kMmapGranularity = kPageSize;
+#elif !defined(_WIN32)
 const uptr kPageSizeBits = 12;
 const uptr kPageSize = 1UL << kPageSizeBits;
 const uptr kCacheLineSize = 64;
-#ifndef _WIN32
 const uptr kMmapGranularity = kPageSize;
 #else
+const uptr kPageSizeBits = 12;
+const uptr kPageSize = 1UL << kPageSizeBits;
+const uptr kCacheLineSize = 64;
 const uptr kMmapGranularity = 1UL << 16;
 #endif
 
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.cc b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.cc
index 28ee960..964c524 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.cc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.cc
@@ -33,7 +33,12 @@ static uptr patch_pc(uptr pc) {
   // Cancel Thumb bit.
   pc = pc & (~1);
 #endif
+#if defined(__powerpc__) || defined(__powerpc64__)
+  // PCs are always 4 byte aligned.
+  return pc - 4;
+#else
   return pc - 1;
+#endif
 }
 
 static void PrintStackFramePrefix(uptr frame_num, uptr pc) {
@@ -138,6 +143,14 @@ void StackTrace::FastUnwindStack(uptr pc, uptr bp,
   }
 }
 
+void StackTrace::PopStackFrames(uptr count) {
+  CHECK(size > count);
+  size -= count;
+  for (uptr i = 0; i < size; i++) {
+    trace[i] = trace[i + count];
+  }
+}
+
 // On 32-bits we don't compress stack traces.
 // On 64-bits we compress stack traces: if a given pc differes slightly from
 // the previous one, we record a 31-bit offset instead of the full pc.
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.h b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.h
index b823a7e..fe2dcf0 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.h
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_stacktrace.h
@@ -45,6 +45,8 @@ struct StackTrace {
 
   void FastUnwindStack(uptr pc, uptr bp, uptr stack_top, uptr stack_bottom);
 
+  void PopStackFrames(uptr count);
+
   static uptr GetCurrentPc();
 
   static uptr CompressStack(StackTrace *stack,
-- 
2.7.4