[compiler-rt] r299867 - [Asan] Eliminate SHADOW_TO_MEM() macro

[Ivan A. Kosarev via llvm-commits]

Author: kosarev
Date: Mon Apr 10 14:13:47 2017
New Revision: 299867

URL: http://llvm.org/viewvc/llvm-project?rev=299867&view=rev
Log:
[Asan] Eliminate SHADOW_TO_MEM() macro
Differential Revision: https://reviews.llvm.org/D31592

Modified:
    compiler-rt/trunk/lib/asan/asan_mapping.h
    compiler-rt/trunk/lib/asan/asan_thread.cc

Modified: compiler-rt/trunk/lib/asan/asan_mapping.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_mapping.h?rev=299867&r1=299866&r2=299867&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_mapping.h (original)
+++ compiler-rt/trunk/lib/asan/asan_mapping.h Mon Apr 10 14:13:47 2017
@@ -191,7 +191,6 @@ static const u64 kWindowsShadowOffset32
 
 #define SHADOW_GRANULARITY (1ULL << SHADOW_SCALE)
 #define MEM_TO_SHADOW(mem) (((mem) >> SHADOW_SCALE) + (SHADOW_OFFSET))
-#define SHADOW_TO_MEM(shadow) (((shadow) - SHADOW_OFFSET) << SHADOW_SCALE)
 
 #define kLowMemBeg      0
 #define kLowMemEnd      (SHADOW_OFFSET ? SHADOW_OFFSET - 1 : 0)

Modified: compiler-rt/trunk/lib/asan/asan_thread.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_thread.cc?rev=299867&r1=299866&r2=299867&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_thread.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_thread.cc Mon Apr 10 14:13:47 2017
@@ -300,24 +300,27 @@ bool AsanThread::GetStackFrameAccessByAd
     return true;
   }
   uptr aligned_addr = addr & ~(SANITIZER_WORDSIZE/8 - 1);  // align addr.
+  uptr mem_ptr = RoundDownTo(aligned_addr, SHADOW_GRANULARITY);
   u8 *shadow_ptr = (u8*)MemToShadow(aligned_addr);
   u8 *shadow_bottom = (u8*)MemToShadow(bottom);
 
   while (shadow_ptr >= shadow_bottom &&
          *shadow_ptr != kAsanStackLeftRedzoneMagic) {
     shadow_ptr--;
+    mem_ptr -= SHADOW_GRANULARITY;
   }
 
   while (shadow_ptr >= shadow_bottom &&
          *shadow_ptr == kAsanStackLeftRedzoneMagic) {
     shadow_ptr--;
+    mem_ptr -= SHADOW_GRANULARITY;
   }
 
   if (shadow_ptr < shadow_bottom) {
     return false;
   }
 
-  uptr* ptr = (uptr*)SHADOW_TO_MEM((uptr)(shadow_ptr + 1));
+  uptr* ptr = (uptr*)(mem_ptr + SHADOW_GRANULARITY);
   CHECK(ptr[0] == kCurrentStackFrameMagic);
   access->offset = addr - (uptr)ptr;
   access->frame_pc = ptr[2];