[hwasan] remove even more stale code

llvm-svn: 340989

2 files changed, 6 insertions, 33 deletions

diff --git a/compiler-rt/lib/hwasan/hwasan_linux.cc b/compiler-rt/lib/hwasan/hwasan_linux.cc
index ac952b35116..d362b0cb460 100644
--- a/compiler-rt/lib/hwasan/hwasan_linux.cc
+++ b/compiler-rt/lib/hwasan/hwasan_linux.cc
@@ -124,19 +124,8 @@ static uptr GetHighMemEnd() {
 }
 
 static void InitializeShadowBaseAddress(uptr shadow_size_bytes) {
-  // Set the shadow memory address to uninitialized.
-  __hwasan_shadow_memory_dynamic_address = kDefaultShadowSentinel;
-  uptr shadow_start = __hwasan_shadow_memory_dynamic_address;
-  // Detect if a dynamic shadow address must be used and find the available
-  // location when necessary. When dynamic address is used, the macro
-  // kLowShadowBeg expands to __hwasan_shadow_memory_dynamic_address which
-  // was just set to kDefaultShadowSentinel.
-  if (shadow_start == kDefaultShadowSentinel) {
-    __hwasan_shadow_memory_dynamic_address = 0;
-    shadow_start = FindDynamicShadowStart(shadow_size_bytes);
-  }
-  // Update the shadow memory address (potentially) used by instrumentation.
-  __hwasan_shadow_memory_dynamic_address = shadow_start;
+  __hwasan_shadow_memory_dynamic_address =
+      FindDynamicShadowStart(shadow_size_bytes);
 }
 
 bool InitShadow() {
diff --git a/compiler-rt/lib/hwasan/hwasan_mapping.h b/compiler-rt/lib/hwasan/hwasan_mapping.h
index e204a5bdbe4..e5e23dc6033 100644
--- a/compiler-rt/lib/hwasan/hwasan_mapping.h
+++ b/compiler-rt/lib/hwasan/hwasan_mapping.h
@@ -18,38 +18,22 @@
 #include "sanitizer_common/sanitizer_internal_defs.h"
 #include "hwasan_interface_internal.h"
 
-// Typical mapping on Linux/x86_64 with fixed shadow mapping:
-// || [0x080000000000, 0x7fffffffffff] || HighMem    ||
-// || [0x008000000000, 0x07ffffffffff] || HighShadow ||
-// || [0x000100000000, 0x007fffffffff] || ShadowGap  ||
-// || [0x000010000000, 0x0000ffffffff] || LowMem     ||
-// || [0x000001000000, 0x00000fffffff] || LowShadow  ||
-// || [0x000000000000, 0x000000ffffff] || ShadowGap  ||
-//
-// and with dynamic shadow mapped at [0x770d59f40000, 0x7f0d59f40000]:
+// Typical mapping on Linux/x86_64:
+// with dynamic shadow mapped at [0x770d59f40000, 0x7f0d59f40000]:
 // || [0x7f0d59f40000, 0x7fffffffffff] || HighMem    ||
 // || [0x7efe2f934000, 0x7f0d59f3ffff] || HighShadow ||
 // || [0x7e7e2f934000, 0x7efe2f933fff] || ShadowGap  ||
 // || [0x770d59f40000, 0x7e7e2f933fff] || LowShadow  ||
 // || [0x000000000000, 0x770d59f3ffff] || LowMem     ||
 
-// Typical mapping on Android/AArch64 (39-bit VMA):
-// || [0x001000000000, 0x007fffffffff] || HighMem    ||
-// || [0x000800000000, 0x000fffffffff] || ShadowGap  ||
-// || [0x000100000000, 0x0007ffffffff] || HighShadow ||
-// || [0x000010000000, 0x0000ffffffff] || LowMem     ||
-// || [0x000001000000, 0x00000fffffff] || LowShadow  ||
-// || [0x000000000000, 0x000000ffffff] || ShadowGap  ||
-//
-// and with dynamic shadow mapped: [0x007477480000, 0x007c77480000]:
+// Typical mapping on Android/AArch64
+// with dynamic shadow mapped: [0x007477480000, 0x007c77480000]:
 // || [0x007c77480000, 0x007fffffffff] || HighMem    ||
 // || [0x007c3ebc8000, 0x007c7747ffff] || HighShadow ||
 // || [0x007bbebc8000, 0x007c3ebc7fff] || ShadowGap  ||
 // || [0x007477480000, 0x007bbebc7fff] || LowShadow  ||
 // || [0x000000000000, 0x00747747ffff] || LowMem     ||
 
-static constexpr u64 kDefaultShadowSentinel = ~(u64)0;
-
 // Reasonable values are 4 (for 1/16th shadow) and 6 (for 1/64th).
 constexpr uptr kShadowScale = 4;
 constexpr uptr kShadowAlignment = 1ULL << kShadowScale;