[compiler-rt] 69fe7ab - Revert "[scudo] Fix the calculating of memory group usage"

[Chia-hung Duan via llvm-commits]

Author: Chia-hung Duan
Date: 2022-10-28T22:15:50Z
New Revision: 69fe7abb393ba7d6ee9c8ff1429316845b5bad37

URL: https://github.com/llvm/llvm-project/commit/69fe7abb393ba7d6ee9c8ff1429316845b5bad37
DIFF: https://github.com/llvm/llvm-project/commit/69fe7abb393ba7d6ee9c8ff1429316845b5bad37.diff

LOG: Revert "[scudo] Fix the calculating of memory group usage"

This reverts commit 6130d67f70ad2e063b4407b6ee31c7db19464fee.

Added: 
    

Modified: 
    compiler-rt/lib/scudo/standalone/primary32.h
    compiler-rt/lib/scudo/standalone/primary64.h

Removed: 
    


################################################################################
diff  --git a/compiler-rt/lib/scudo/standalone/primary32.h b/compiler-rt/lib/scudo/standalone/primary32.h
index a3d908cee9e5..6e791a127df6 100644
--- a/compiler-rt/lib/scudo/standalone/primary32.h
+++ b/compiler-rt/lib/scudo/standalone/primary32.h
@@ -708,10 +708,8 @@ template <typename Config> class SizeClassAllocator32 {
       if (AllocatedGroupSize == 0)
         continue;
 
-      // TransferBatches are pushed in front of BG.Batches. The first one may
-      // not have all caches used.
       const uptr NumBlocks = (BG.Batches.size() - 1) * BG.MaxCachedPerBatch +
-                             BG.Batches.front()->getCount();
+                             BG.Batches.back()->getCount();
       const uptr BytesInBG = NumBlocks * BlockSize;
       // Given the randomness property, we try to release the pages only if the
       // bytes used by free blocks exceed certain proportion of allocated

diff  --git a/compiler-rt/lib/scudo/standalone/primary64.h b/compiler-rt/lib/scudo/standalone/primary64.h
index c64f9b8e062f..a3684c9d4586 100644
--- a/compiler-rt/lib/scudo/standalone/primary64.h
+++ b/compiler-rt/lib/scudo/standalone/primary64.h
@@ -702,49 +702,16 @@ template <typename Config> class SizeClassAllocator64 {
           BG.PushedBlocks - BG.PushedBlocksAtLastCheckpoint;
       if (PushedBytesDelta * BlockSize < PageSize)
         continue;
-
-      // Group boundary does not necessarily have the same alignment as Region.
-      // It may sit across a Region boundary. Which means that we may have the
-      // following two cases,
-      //
-      // 1. Group boundary sits before RegionBeg.
-      //
-      //                (BatchGroupBeg)
-      // batchGroupBase  RegionBeg       BatchGroupEnd
-      //        |            |                |
-      //        v            v                v
-      //        +------------+----------------+
-      //         \                           /
-      //          ------   GroupSize   ------
-      //
-      // 2. Group boundary sits after RegionBeg.
-      //
-      //               (BatchGroupBeg)
-      //    RegionBeg  batchGroupBase               BatchGroupEnd
-      //        |           |                             |
-      //        v           v                             v
-      //        +-----------+-----------------------------+
-      //                     \                           /
-      //                      ------   GroupSize   ------
-      //
-      // Note that in the first case, the group range before RegionBeg is never
-      // used. Therefore, while calculating the used group size, we should
-      // exclude that part to get the correct size.
-      const uptr BatchGroupBeg =
-          Max(batchGroupBase(BG.GroupId, CompactPtrBase), Region->RegionBeg);
-      DCHECK_GE(AllocatedUserEnd, BatchGroupBeg);
       const uptr BatchGroupEnd =
           batchGroupBase(BG.GroupId, CompactPtrBase) + GroupSize;
       const uptr AllocatedGroupSize = AllocatedUserEnd >= BatchGroupEnd
-                                          ? BatchGroupEnd - BatchGroupBeg
-                                          : AllocatedUserEnd - BatchGroupBeg;
+                                          ? GroupSize
+                                          : AllocatedUserEnd - BatchGroupEnd;
       if (AllocatedGroupSize == 0)
         continue;
 
-      // TransferBatches are pushed in front of BG.Batches. The first one may
-      // not have all caches used.
       const uptr NumBlocks = (BG.Batches.size() - 1) * BG.MaxCachedPerBatch +
-                             BG.Batches.front()->getCount();
+                             BG.Batches.back()->getCount();
       const uptr BytesInBG = NumBlocks * BlockSize;
       // Given the randomness property, we try to release the pages only if the
       // bytes used by free blocks exceed certain proportion of group size. Note