[compiler-rt] ab658a4 - [HWASAN] Removed right_aligned from HWASAN allocator Metadata.

[Kirill Stoimenov via llvm-commits]

Author: Kirill Stoimenov
Date: 2022-12-08T19:55:39Z
New Revision: ab658a48479b9c9a5c6eaee199357f1ee4bb4124

URL: https://github.com/llvm/llvm-project/commit/ab658a48479b9c9a5c6eaee199357f1ee4bb4124
DIFF: https://github.com/llvm/llvm-project/commit/ab658a48479b9c9a5c6eaee199357f1ee4bb4124.diff

LOG: [HWASAN] Removed right_aligned from HWASAN allocator Metadata.

This came up during review of D139464. Looks like this filed is always set to false to it is basically unused.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D139654

Added: 
    

Modified: 
    compiler-rt/lib/hwasan/hwasan_allocator.cpp
    compiler-rt/lib/hwasan/hwasan_allocator.h

Removed: 
    


################################################################################
diff  --git a/compiler-rt/lib/hwasan/hwasan_allocator.cpp b/compiler-rt/lib/hwasan/hwasan_allocator.cpp
index 842455150c7b..0f7a0ac8f000 100644
--- a/compiler-rt/lib/hwasan/hwasan_allocator.cpp
+++ b/compiler-rt/lib/hwasan/hwasan_allocator.cpp
@@ -46,16 +46,7 @@ bool HwasanChunkView::IsAllocated() const {
          metadata_->get_requested_size();
 }
 
-// Aligns the 'addr' right to the granule boundary.
-static uptr AlignRight(uptr addr, uptr requested_size) {
-  uptr tail_size = requested_size % kShadowAlignment;
-  if (!tail_size) return addr;
-  return addr + kShadowAlignment - tail_size;
-}
-
 uptr HwasanChunkView::Beg() const {
-  if (metadata_ && metadata_->right_aligned)
-    return AlignRight(block_, metadata_->get_requested_size());
   return block_;
 }
 uptr HwasanChunkView::End() const {
@@ -159,7 +150,6 @@ static void *HwasanAllocate(StackTrace *stack, uptr orig_size, uptr alignment,
       reinterpret_cast<Metadata *>(allocator.GetMetaData(allocated));
   meta->set_requested_size(orig_size);
   meta->alloc_context_id = StackDepotPut(*stack);
-  meta->right_aligned = false;
   if (zeroise) {
     internal_memset(allocated, 0, size);
   } else if (flags()->max_malloc_fill_size > 0) {
@@ -353,13 +343,7 @@ static uptr AllocationSize(const void *tagged_ptr) {
   if (!untagged_ptr) return 0;
   const void *beg = allocator.GetBlockBegin(untagged_ptr);
   Metadata *b = (Metadata *)allocator.GetMetaData(untagged_ptr);
-  if (b->right_aligned) {
-    if (beg != reinterpret_cast<void *>(RoundDownTo(
-                   reinterpret_cast<uptr>(untagged_ptr), kShadowAlignment)))
-      return 0;
-  } else {
-    if (beg != untagged_ptr) return 0;
-  }
+  if (beg != untagged_ptr) return 0;
   return b->get_requested_size();
 }
 

diff  --git a/compiler-rt/lib/hwasan/hwasan_allocator.h b/compiler-rt/lib/hwasan/hwasan_allocator.h
index bae53b565592..c38b28d12624 100644
--- a/compiler-rt/lib/hwasan/hwasan_allocator.h
+++ b/compiler-rt/lib/hwasan/hwasan_allocator.h
@@ -32,8 +32,7 @@ namespace __hwasan {
 
 struct Metadata {
   u32 requested_size_low;
-  u32 requested_size_high : 31;
-  u32 right_aligned : 1;
+  u32 requested_size_high;
   u32 alloc_context_id;
   u64 get_requested_size() {
     return (static_cast<u64>(requested_size_high) << 32) + requested_size_low;