[ASan] Revert r168040 and r168043 and take a cleaner solution suggested by Kostya: return the known frame name for fake stack instead of looking it up.
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@168046 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/asan/asan_thread.cc b/lib/asan/asan_thread.cc
index df764a9..bafa5a8 100644
--- a/lib/asan/asan_thread.cc
+++ b/lib/asan/asan_thread.cc
@@ -118,41 +118,35 @@
const char *AsanThread::GetFrameNameByAddr(uptr addr, uptr *offset) {
uptr bottom = 0;
- bool is_fake_stack = false;
if (AddrIsInStack(addr)) {
bottom = stack_bottom();
} else {
bottom = fake_stack().AddrIsInFakeStack(addr);
CHECK(bottom);
- is_fake_stack = true;
+ *offset = addr - bottom;
+ return (const char *)((uptr*)bottom)[1];
}
uptr aligned_addr = addr & ~(__WORDSIZE/8 - 1); // align addr.
u8 *shadow_ptr = (u8*)MemToShadow(aligned_addr);
u8 *shadow_bottom = (u8*)MemToShadow(bottom);
while (shadow_ptr >= shadow_bottom &&
- *shadow_ptr != kAsanStackLeftRedzoneMagic &&
- *shadow_ptr != kAsanStackAfterReturnLeftMagic) {
+ *shadow_ptr != kAsanStackLeftRedzoneMagic) {
shadow_ptr--;
}
while (shadow_ptr >= shadow_bottom &&
- (*shadow_ptr == kAsanStackLeftRedzoneMagic ||
- *shadow_ptr == kAsanStackAfterReturnLeftMagic)) {
+ *shadow_ptr == kAsanStackLeftRedzoneMagic) {
shadow_ptr--;
}
if (shadow_ptr < shadow_bottom) {
- // If we're one byte below the fake stack bottom, we've found the frame.
- if (!is_fake_stack || (*shadow_bottom != kAsanStackAfterReturnLeftMagic)) {
- *offset = 0;
- return "UNKNOWN";
- }
+ *offset = 0;
+ return "UNKNOWN";
}
uptr* ptr = (uptr*)SHADOW_TO_MEM((uptr)(shadow_ptr + 1));
- CHECK((ptr[0] == kCurrentStackFrameMagic) ||
- (is_fake_stack && ptr[0] == kRetiredStackFrameMagic));
+ CHECK(ptr[0] == kCurrentStackFrameMagic);
*offset = addr - (uptr)ptr;
return (const char*)ptr[1];
}