split bitmap code into separate header and source file

CMakeLists.txt

@@ -29,6 +29,7 @@ set(mi_sources
     src/stats.c
     src/random.c
     src/os.c
+    src/bitmap.c
     src/arena.c
     src/region.c
     src/segment.c

ide/vs2017/mimalloc-override.vcxproj

@@ -215,6 +215,7 @@
     <ClInclude Include="..\..\include\mimalloc-new-delete.h" />
     <ClInclude Include="..\..\include\mimalloc-override.h" />
     <ClInclude Include="..\..\include\mimalloc-types.h" />
+    <ClInclude Include="..\..\src\bitmap.h" />
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\..\src\alloc-aligned.c">
@@ -232,6 +233,7 @@
     <ClCompile Include="..\..\src\alloc-posix.c" />
     <ClCompile Include="..\..\src\alloc.c" />
     <ClCompile Include="..\..\src\arena.c" />
+    <ClCompile Include="..\..\src\bitmap.c" />
     <ClCompile Include="..\..\src\heap.c" />
     <ClCompile Include="..\..\src\init.c" />
     <ClCompile Include="..\..\src\region.c" />
@@ -251,4 +253,4 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
-</Project>
+</Project>

ide/vs2017/mimalloc-override.vcxproj.filters

@@ -29,6 +29,9 @@
     <ClInclude Include="..\..\include\mimalloc-new-delete.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\src\bitmap.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\..\src\alloc.c">
@@ -76,5 +79,8 @@
     <ClCompile Include="..\..\src\random.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\bitmap.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
-</Project>
+</Project>

ide/vs2017/mimalloc.vcxproj

@@ -230,6 +230,7 @@
     <ClCompile Include="..\..\src\alloc-posix.c" />
     <ClCompile Include="..\..\src\alloc.c" />
     <ClCompile Include="..\..\src\arena.c" />
+    <ClCompile Include="..\..\src\bitmap.c" />
     <ClCompile Include="..\..\src\heap.c" />
     <ClCompile Include="..\..\src\init.c" />
     <ClCompile Include="..\..\src\region.c" />
@@ -253,6 +254,7 @@
     <ClInclude Include="$(ProjectDir)..\..\include\mimalloc-override.h" />
     <ClInclude Include="$(ProjectDir)..\..\include\mimalloc-types.h" />
     <ClInclude Include="..\..\include\mimalloc-new-delete.h" />
+    <ClInclude Include="..\..\src\bitmap.h" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">

ide/vs2017/mimalloc.vcxproj.filters

@@ -59,6 +59,9 @@
     <ClCompile Include="..\..\src\random.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\bitmap.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="$(ProjectDir)..\..\include\mimalloc.h">
@@ -79,5 +82,8 @@
     <ClInclude Include="..\..\include\mimalloc-new-delete.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\src\bitmap.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
-</Project>
+</Project>

ide/vs2019/mimalloc-override.vcxproj

@@ -215,6 +215,7 @@
     <ClInclude Include="..\..\include\mimalloc-new-delete.h" />
     <ClInclude Include="..\..\include\mimalloc-override.h" />
     <ClInclude Include="..\..\include\mimalloc-types.h" />
+    <ClInclude Include="..\..\src\bitmap.h" />
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\..\src\alloc-aligned.c">
@@ -232,9 +233,7 @@
     <ClCompile Include="..\..\src\alloc-posix.c" />
     <ClCompile Include="..\..\src\alloc.c" />
     <ClCompile Include="..\..\src\arena.c" />
-    <ClCompile Include="..\..\src\bitmap.inc.c">
+    <ClCompile Include="..\..\src\bitmap.c" />
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
-    </ClCompile>
     <ClCompile Include="..\..\src\heap.c" />
     <ClCompile Include="..\..\src\init.c" />
     <ClCompile Include="..\..\src\region.c" />

ide/vs2019/mimalloc-override.vcxproj.filters

@@ -40,15 +40,15 @@
     <ClCompile Include="..\..\src\arena.c">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="..\..\src\bitmap.inc.c">
-      <Filter>Source Files</Filter>
-    </ClCompile>
     <ClCompile Include="..\..\src\random.c">
       <Filter>Source Files</Filter>
     </ClCompile>
     <ClCompile Include="..\..\src\options.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\bitmap.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="$(ProjectDir)..\..\include\mimalloc.h">
@@ -69,6 +69,9 @@
     <ClInclude Include="..\..\include\mimalloc-types.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\src\bitmap.h">
+      <Filter>Source Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <Filter Include="Header Files">

ide/vs2019/mimalloc.vcxproj

@@ -220,8 +220,8 @@
     <ClCompile Include="..\..\src\alloc-posix.c" />
     <ClCompile Include="..\..\src\alloc.c" />
     <ClCompile Include="..\..\src\arena.c" />
-    <ClCompile Include="..\..\src\bitmap.inc.c">
+    <ClCompile Include="..\..\src\bitmap.c">
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">false</ExcludedFromBuild>
     </ClCompile>
     <ClCompile Include="..\..\src\heap.c" />
     <ClCompile Include="..\..\src\init.c" />
@@ -246,6 +246,7 @@
     <ClInclude Include="$(ProjectDir)..\..\include\mimalloc-override.h" />
     <ClInclude Include="$(ProjectDir)..\..\include\mimalloc-types.h" />
     <ClInclude Include="..\..\include\mimalloc-new-delete.h" />
+    <ClInclude Include="..\..\src\bitmap.h" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">

ide/vs2019/mimalloc.vcxproj.filters

@@ -46,10 +46,10 @@
     <ClCompile Include="..\..\src\arena.c">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="..\..\src\bitmap.inc.c">
+    <ClCompile Include="..\..\src\random.c">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="..\..\src\random.c">
+    <ClCompile Include="..\..\src\bitmap.c">
       <Filter>Source Files</Filter>
     </ClCompile>
   </ItemGroup>
@@ -72,6 +72,9 @@
     <ClInclude Include="$(ProjectDir)..\..\include\mimalloc-types.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\src\bitmap.h">
+      <Filter>Source Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <Filter Include="Header Files">
@@ -81,4 +84,4 @@
       <UniqueIdentifier>{852a14ae-6dde-4e95-8077-ca705e97e5af}</UniqueIdentifier>
     </Filter>
   </ItemGroup>
-</Project>
+</Project>

include/mimalloc-internal.h

@@ -770,6 +770,7 @@ static inline size_t mi_ctz(uintptr_t x) {
 
 #elif defined(_MSC_VER) 
 
+#include <limits.h>       // LONG_MAX
 #define MI_HAVE_FAST_BITSCAN
 static inline size_t mi_clz(uintptr_t x) {
   if (x==0) return MI_INTPTR_BITS;

src/arena.c

@@ -32,7 +32,7 @@ of 256MiB in practice.
 #include <string.h>  // memset
 #include <errno.h> // ENOMEM
 
-#include "bitmap.inc.c"  // atomic bitmap
+#include "bitmap.h"  // atomic bitmap
 
 
 // os.c
@@ -105,7 +105,7 @@ static size_t mi_block_count_of_size(size_t size) {
 static bool mi_arena_alloc(mi_arena_t* arena, size_t blocks, mi_bitmap_index_t* bitmap_idx)
 {
   size_t idx = mi_atomic_load_acquire(&arena->search_idx);  // start from last search
-  if (mi_bitmap_try_find_from_claim_across(arena->blocks_inuse, arena->field_count, idx, blocks, bitmap_idx)) {
+  if (_mi_bitmap_try_find_from_claim_across(arena->blocks_inuse, arena->field_count, idx, blocks, bitmap_idx)) {
     mi_atomic_store_release(&arena->search_idx, idx);  // start search from here next time
     return true;
   };
@@ -126,7 +126,7 @@ static void* mi_arena_alloc_from(mi_arena_t* arena, size_t arena_index, size_t n
   // claimed it! set the dirty bits (todo: no need for an atomic op here?)
   void* p  = arena->start + (mi_bitmap_index_bit(bitmap_index)*MI_ARENA_BLOCK_SIZE);
   *memid   = mi_arena_id_create(arena_index, bitmap_index);
-  *is_zero = mi_bitmap_claim_across(arena->blocks_dirty, arena->field_count, needed_bcount, bitmap_index, NULL);
+  *is_zero = _mi_bitmap_claim_across(arena->blocks_dirty, arena->field_count, needed_bcount, bitmap_index, NULL);
   *large   = arena->is_large;
   if (arena->is_committed) {
     // always committed
@@ -135,7 +135,7 @@ static void* mi_arena_alloc_from(mi_arena_t* arena, size_t arena_index, size_t n
   else if (*commit) {
     // arena not committed as a whole, but commit requested: ensure commit now
     bool any_uncommitted;
-    mi_bitmap_claim_across(arena->blocks_committed, arena->field_count, needed_bcount, bitmap_index, &any_uncommitted);
+    _mi_bitmap_claim_across(arena->blocks_committed, arena->field_count, needed_bcount, bitmap_index, &any_uncommitted);
     if (any_uncommitted) {
       bool commit_zero;
       _mi_os_commit(p, needed_bcount * MI_ARENA_BLOCK_SIZE, &commit_zero, tld->stats);
@@ -144,7 +144,7 @@ static void* mi_arena_alloc_from(mi_arena_t* arena, size_t arena_index, size_t n
   }
   else {
     // no need to commit, but check if already fully committed
-    *commit = mi_bitmap_is_claimed_across(arena->blocks_committed, arena->field_count, needed_bcount, bitmap_index);
+    *commit = _mi_bitmap_is_claimed_across(arena->blocks_committed, arena->field_count, needed_bcount, bitmap_index);
   }
   return p;
 }
@@ -235,7 +235,7 @@ void _mi_arena_free(void* p, size_t size, size_t memid, bool all_committed, mi_s
       return;
     }
     const size_t blocks = mi_block_count_of_size(size);
-    bool ones = mi_bitmap_unclaim_across(arena->blocks_inuse, arena->field_count, blocks, bitmap_idx);
+    bool ones = _mi_bitmap_unclaim_across(arena->blocks_inuse, arena->field_count, blocks, bitmap_idx);
     if (!ones) {
       _mi_error_message(EAGAIN, "trying to free an already freed block: %p, size %zu\n", p, size);
       return;
@@ -287,7 +287,7 @@ bool mi_manage_os_memory(void* start, size_t size, bool is_committed, bool is_la
   if (post > 0) {
     // don't use leftover bits at the end
     mi_bitmap_index_t postidx = mi_bitmap_index_create(fields - 1, MI_BITMAP_FIELD_BITS - post);
-    mi_bitmap_claim(arena->blocks_inuse, fields, post, postidx, NULL);
+    _mi_bitmap_claim(arena->blocks_inuse, fields, post, postidx, NULL);
   }
 
   mi_arena_add(arena);

src/bitmap.c

@@ -1,63 +1,30 @@
 /* ----------------------------------------------------------------------------
-Copyright (c) 2019, Microsoft Research, Daan Leijen
+Copyright (c) 2019,2020 Microsoft Research, Daan Leijen
 This is free software; you can redistribute it and/or modify it under the
 terms of the MIT license. A copy of the license can be found in the file
 "LICENSE" at the root of this distribution.
 -----------------------------------------------------------------------------*/
 
 /* ----------------------------------------------------------------------------
-This file is meant to be included in other files for efficiency.
+Concurrent bitmap that can set/reset sequences of bits atomically,
-It implements a bitmap that can set/reset sequences of bits atomically
+represeted as an array of fields where each field is a machine word (`uintptr_t`)
-and is used to concurrently claim memory ranges.
 
-A bitmap is an array of fields where each field is a machine word (`uintptr_t`)
+There are two api's; the standard one cannot have sequences that cross
+between the bitmap fields (and a sequence must be <= MI_BITMAP_FIELD_BITS).
+(this is used in region allocation)
 
-A current limitation is that the bit sequences cannot cross fields
+The `_across` postfixed functions do allow sequences that can cross over
-and that the sequence must be smaller or equal to the bits in a field.
+between the fields. (This is used in arena allocation)
 ---------------------------------------------------------------------------- */
-#pragma once
-#ifndef MI_BITMAP_C
-#define MI_BITMAP_C
 
 #include "mimalloc.h"
 #include "mimalloc-internal.h"
+#include "bitmap.h"
 
 /* -----------------------------------------------------------
   Bitmap definition
 ----------------------------------------------------------- */
 
-#define MI_BITMAP_FIELD_BITS   (8*MI_INTPTR_SIZE)
-#define MI_BITMAP_FIELD_FULL   (~((uintptr_t)0))   // all bits set
-
-// An atomic bitmap of `uintptr_t` fields
-typedef _Atomic(uintptr_t)  mi_bitmap_field_t;
-typedef mi_bitmap_field_t*           mi_bitmap_t;
-
-// A bitmap index is the index of the bit in a bitmap.
-typedef size_t mi_bitmap_index_t;
-
-// Create a bit index.
-static inline mi_bitmap_index_t mi_bitmap_index_create(size_t idx, size_t bitidx) {
-  mi_assert_internal(bitidx < MI_BITMAP_FIELD_BITS);
-  return (idx*MI_BITMAP_FIELD_BITS) + bitidx;
-}
-
-// Get the field index from a bit index.
-static inline size_t mi_bitmap_index_field(mi_bitmap_index_t bitmap_idx) {
-  return (bitmap_idx / MI_BITMAP_FIELD_BITS);
-}
-
-// Get the bit index in a bitmap field
-static inline size_t mi_bitmap_index_bit_in_field(mi_bitmap_index_t bitmap_idx) {
-  return (bitmap_idx % MI_BITMAP_FIELD_BITS);
-}
-
-// Get the full bit index
-static inline size_t mi_bitmap_index_bit(mi_bitmap_index_t bitmap_idx) {
-  return bitmap_idx;
-}
-
-
 // The bit mask for a given number of blocks at a specified bit index.
 static inline uintptr_t mi_bitmap_mask_(size_t count, size_t bitidx) {
   mi_assert_internal(count + bitidx <= MI_BITMAP_FIELD_BITS);
@@ -73,29 +40,9 @@ static inline uintptr_t mi_bitmap_mask_(size_t count, size_t bitidx) {
   Claim a bit sequence atomically
 ----------------------------------------------------------- */
 
-// Try to atomically claim a sequence of `count` bits at in `idx`
-// in the bitmap field. Returns `true` on success.
-static inline bool mi_bitmap_try_claim_field(mi_bitmap_t bitmap, size_t bitmap_fields, const size_t count, mi_bitmap_index_t bitmap_idx) {
-  const size_t idx = mi_bitmap_index_field(bitmap_idx);
-  const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
-  const uintptr_t mask = mi_bitmap_mask_(count, bitidx);
-  mi_assert_internal(bitmap_fields > idx); UNUSED(bitmap_fields);
-  mi_assert_internal(bitidx + count <= MI_BITMAP_FIELD_BITS);
-
-  uintptr_t field = mi_atomic_load_relaxed(&bitmap[idx]);
-  if ((field & mask) == 0) { // free?
-    if (mi_atomic_cas_strong_acq_rel(&bitmap[idx], &field, (field|mask))) {
-      // claimed!
-      return true;
-    }
-  }
-  return false;
-}
-
-
 // Try to atomically claim a sequence of `count` bits in a single
 // field at `idx` in `bitmap`. Returns `true` on success.
-static inline bool mi_bitmap_try_find_claim_field(mi_bitmap_t bitmap, size_t idx, const size_t count, mi_bitmap_index_t* bitmap_idx)
+bool _mi_bitmap_try_find_claim_field(mi_bitmap_t bitmap, size_t idx, const size_t count, mi_bitmap_index_t* bitmap_idx)
 {
   mi_assert_internal(bitmap_idx != NULL);
   mi_assert_internal(count <= MI_BITMAP_FIELD_BITS);
@@ -150,27 +97,28 @@ static inline bool mi_bitmap_try_find_claim_field(mi_bitmap_t bitmap, size_t idx
 
 // Starts at idx, and wraps around to search in all `bitmap_fields` fields.
 // For now, `count` can be at most MI_BITMAP_FIELD_BITS and will never cross fields.
-static inline bool mi_bitmap_try_find_from_claim(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx) {
+bool _mi_bitmap_try_find_from_claim(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx) {
   size_t idx = start_field_idx;
   for (size_t visited = 0; visited < bitmap_fields; visited++, idx++) {
     if (idx >= bitmap_fields) idx = 0; // wrap
-    if (mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx)) {
+    if (_mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx)) {
       return true;
     }
   }
   return false;
 }
 
+/*
 // Find `count` bits of 0 and set them to 1 atomically; returns `true` on success.
 // For now, `count` can be at most MI_BITMAP_FIELD_BITS and will never span fields.
-static inline bool mi_bitmap_try_find_claim(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t count, mi_bitmap_index_t* bitmap_idx) {
+bool _mi_bitmap_try_find_claim(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t count, mi_bitmap_index_t* bitmap_idx) {
-  return mi_bitmap_try_find_from_claim(bitmap, bitmap_fields, 0, count, bitmap_idx);
+  return _mi_bitmap_try_find_from_claim(bitmap, bitmap_fields, 0, count, bitmap_idx);
 }
-
+*/
 
 // Set `count` bits at `bitmap_idx` to 0 atomically
 // Returns `true` if all `count` bits were 1 previously.
-static inline bool mi_bitmap_unclaim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+bool mi_bitmap_unclaim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
   const size_t idx = mi_bitmap_index_field(bitmap_idx);
   const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
   const uintptr_t mask = mi_bitmap_mask_(count, bitidx);
@@ -183,7 +131,7 @@ static inline bool mi_bitmap_unclaim(mi_bitmap_t bitmap, size_t bitmap_fields, s
 
 // Set `count` bits at `bitmap_idx` to 1 atomically
 // Returns `true` if all `count` bits were 0 previously. `any_zero` is `true` if there was at least one zero bit.
-static inline bool mi_bitmap_claim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* any_zero) {
+bool _mi_bitmap_claim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* any_zero) {
   const size_t idx = mi_bitmap_index_field(bitmap_idx);
   const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
   const uintptr_t mask = mi_bitmap_mask_(count, bitidx);
@@ -195,7 +143,7 @@ static inline bool mi_bitmap_claim(mi_bitmap_t bitmap, size_t bitmap_fields, siz
 }
 
 // Returns `true` if all `count` bits were 1. `any_ones` is `true` if there was at least one bit set to one.
-static inline bool mi_bitmap_is_claimedx(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* any_ones) {
+static bool mi_bitmap_is_claimedx(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* any_ones) {
   const size_t idx = mi_bitmap_index_field(bitmap_idx);
   const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
   const uintptr_t mask = mi_bitmap_mask_(count, bitidx);
@@ -205,11 +153,11 @@ static inline bool mi_bitmap_is_claimedx(mi_bitmap_t bitmap, size_t bitmap_field
   return ((field & mask) == mask);
 }
 
-static inline bool mi_bitmap_is_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+bool _mi_bitmap_is_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
   return mi_bitmap_is_claimedx(bitmap, bitmap_fields, count, bitmap_idx, NULL);
 }
 
-static inline bool mi_bitmap_is_any_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+bool _mi_bitmap_is_any_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
   bool any_ones;
   mi_bitmap_is_claimedx(bitmap, bitmap_fields, count, bitmap_idx, &any_ones);
   return any_ones;
@@ -223,7 +171,7 @@ static inline bool mi_bitmap_is_any_claimed(mi_bitmap_t bitmap, size_t bitmap_fi
 
 // Try to atomically claim a sequence of `count` bits starting from the field 
 // at `idx` in `bitmap` and crossing into subsequent fields. Returns `true` on success.
-static inline bool mi_bitmap_try_find_claim_field_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t idx, const size_t count, const size_t retries, mi_bitmap_index_t* bitmap_idx)
+static bool mi_bitmap_try_find_claim_field_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t idx, const size_t count, const size_t retries, mi_bitmap_index_t* bitmap_idx)
 {
   mi_assert_internal(bitmap_idx != NULL);
   
@@ -233,7 +181,7 @@ static inline bool mi_bitmap_try_find_claim_field_across(mi_bitmap_t bitmap, siz
   const size_t initial = mi_clz(map);  // count of initial zeros starting at idx
   mi_assert_internal(initial >= 0 && initial <= MI_BITMAP_FIELD_BITS);
   if (initial == 0)     return false;
-  if (initial >= count) return mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx);     // no need to cross fields
+  if (initial >= count) return _mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx);     // no need to cross fields
   if (_mi_divide_up(count - initial, MI_BITMAP_FIELD_BITS) >= (bitmap_fields - idx)) return false; // not enough entries
 
   // scan ahead
@@ -311,15 +259,15 @@ rollback:
 
 // Find `count` bits of zeros and set them to 1 atomically; returns `true` on success.
 // Starts at idx, and wraps around to search in all `bitmap_fields` fields.
-static inline bool mi_bitmap_try_find_from_claim_across(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx) {
+bool _mi_bitmap_try_find_from_claim_across(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx) {
   mi_assert_internal(count > 0);
-  if (count==1) return mi_bitmap_try_find_from_claim(bitmap, bitmap_fields, start_field_idx, count, bitmap_idx);
+  if (count==1) return _mi_bitmap_try_find_from_claim(bitmap, bitmap_fields, start_field_idx, count, bitmap_idx);
   size_t idx = start_field_idx;
   for (size_t visited = 0; visited < bitmap_fields; visited++, idx++) {
     if (idx >= bitmap_fields) idx = 0; // wrap
     // try to claim inside the field
     if (count <= MI_BITMAP_FIELD_BITS) {
-      if (mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx)) {
+      if (_mi_bitmap_try_find_claim_field(bitmap, idx, count, bitmap_idx)) {
         return true;
       }
     }
@@ -332,7 +280,7 @@ static inline bool mi_bitmap_try_find_from_claim_across(mi_bitmap_t bitmap, cons
 }
 
 // Helper for masks across fields; returns the mid count, post_mask may be 0
-static inline size_t mi_bitmap_mask_across(mi_bitmap_index_t bitmap_idx, size_t bitmap_fields, size_t count, uintptr_t* pre_mask, uintptr_t* mid_mask, uintptr_t* post_mask) {
+static size_t mi_bitmap_mask_across(mi_bitmap_index_t bitmap_idx, size_t bitmap_fields, size_t count, uintptr_t* pre_mask, uintptr_t* mid_mask, uintptr_t* post_mask) {
   UNUSED_RELEASE(bitmap_fields);
   const size_t bitidx = mi_bitmap_index_bit_in_field(bitmap_idx);
   if (mi_likely(bitidx + count <= MI_BITMAP_FIELD_BITS)) {
@@ -358,7 +306,7 @@ static inline size_t mi_bitmap_mask_across(mi_bitmap_index_t bitmap_idx, size_t
 
 // Set `count` bits at `bitmap_idx` to 0 atomically
 // Returns `true` if all `count` bits were 1 previously.
-static inline bool mi_bitmap_unclaim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+bool _mi_bitmap_unclaim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
   size_t idx = mi_bitmap_index_field(bitmap_idx);
   uintptr_t pre_mask;
   uintptr_t mid_mask;
@@ -381,7 +329,7 @@ static inline bool mi_bitmap_unclaim_across(mi_bitmap_t bitmap, size_t bitmap_fi
 
 // Set `count` bits at `bitmap_idx` to 1 atomically
 // Returns `true` if all `count` bits were 0 previously. `any_zero` is `true` if there was at least one zero bit.
-static inline bool mi_bitmap_claim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* pany_zero) {
+bool _mi_bitmap_claim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* pany_zero) {
   size_t idx = mi_bitmap_index_field(bitmap_idx);
   uintptr_t pre_mask;
   uintptr_t mid_mask;
@@ -410,7 +358,7 @@ static inline bool mi_bitmap_claim_across(mi_bitmap_t bitmap, size_t bitmap_fiel
 
 // Returns `true` if all `count` bits were 1. 
 // `any_ones` is `true` if there was at least one bit set to one.
-static inline bool mi_bitmap_is_claimedx_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* pany_ones) {
+static bool mi_bitmap_is_claimedx_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* pany_ones) {
   size_t idx = mi_bitmap_index_field(bitmap_idx);
   uintptr_t pre_mask;
   uintptr_t mid_mask;
@@ -436,14 +384,14 @@ static inline bool mi_bitmap_is_claimedx_across(mi_bitmap_t bitmap, size_t bitma
   return all_ones;
 }
 
-static inline bool mi_bitmap_is_claimed_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+bool _mi_bitmap_is_claimed_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
   return mi_bitmap_is_claimedx_across(bitmap, bitmap_fields, count, bitmap_idx, NULL);
 }
 
-static inline bool mi_bitmap_is_any_claimed_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
+/*
+bool _mi_bitmap_is_any_claimed_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx) {
   bool any_ones;
   mi_bitmap_is_claimedx_across(bitmap, bitmap_fields, count, bitmap_idx, &any_ones);
   return any_ones;
 }
-
+*/
-#endif

src/bitmap.h

@@ -0,0 +1,101 @@
+/* ----------------------------------------------------------------------------
+Copyright (c) 2019,2020 Microsoft Research, Daan Leijen
+This is free software; you can redistribute it and/or modify it under the
+terms of the MIT license. A copy of the license can be found in the file
+"LICENSE" at the root of this distribution.
+-----------------------------------------------------------------------------*/
+
+/* ----------------------------------------------------------------------------
+Concurrent bitmap that can set/reset sequences of bits atomically,
+represeted as an array of fields where each field is a machine word (`uintptr_t`)
+
+There are two api's; the standard one cannot have sequences that cross
+between the bitmap fields (and a sequence must be <= MI_BITMAP_FIELD_BITS).
+(this is used in region allocation)
+
+The `_across` postfixed functions do allow sequences that can cross over
+between the fields. (This is used in arena allocation)
+---------------------------------------------------------------------------- */
+#pragma once
+#ifndef MI_BITMAP_H
+#define MI_BITMAP_H
+
+/* -----------------------------------------------------------
+  Bitmap definition
+----------------------------------------------------------- */
+
+#define MI_BITMAP_FIELD_BITS   (8*MI_INTPTR_SIZE)
+#define MI_BITMAP_FIELD_FULL   (~((uintptr_t)0))   // all bits set
+
+// An atomic bitmap of `uintptr_t` fields
+typedef _Atomic(uintptr_t)  mi_bitmap_field_t;
+typedef mi_bitmap_field_t*  mi_bitmap_t;
+
+// A bitmap index is the index of the bit in a bitmap.
+typedef size_t mi_bitmap_index_t;
+
+// Create a bit index.
+static inline mi_bitmap_index_t mi_bitmap_index_create(size_t idx, size_t bitidx) {
+  mi_assert_internal(bitidx < MI_BITMAP_FIELD_BITS);
+  return (idx*MI_BITMAP_FIELD_BITS) + bitidx;
+}
+
+// Get the field index from a bit index.
+static inline size_t mi_bitmap_index_field(mi_bitmap_index_t bitmap_idx) {
+  return (bitmap_idx / MI_BITMAP_FIELD_BITS);
+}
+
+// Get the bit index in a bitmap field
+static inline size_t mi_bitmap_index_bit_in_field(mi_bitmap_index_t bitmap_idx) {
+  return (bitmap_idx % MI_BITMAP_FIELD_BITS);
+}
+
+// Get the full bit index
+static inline size_t mi_bitmap_index_bit(mi_bitmap_index_t bitmap_idx) {
+  return bitmap_idx;
+}
+
+/* -----------------------------------------------------------
+  Claim a bit sequence atomically
+----------------------------------------------------------- */
+
+// Try to atomically claim a sequence of `count` bits in a single
+// field at `idx` in `bitmap`. Returns `true` on success.
+bool _mi_bitmap_try_find_claim_field(mi_bitmap_t bitmap, size_t idx, const size_t count, mi_bitmap_index_t* bitmap_idx);
+
+// Starts at idx, and wraps around to search in all `bitmap_fields` fields.
+// For now, `count` can be at most MI_BITMAP_FIELD_BITS and will never cross fields.
+bool _mi_bitmap_try_find_from_claim(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx);
+
+// Set `count` bits at `bitmap_idx` to 0 atomically
+// Returns `true` if all `count` bits were 1 previously.
+bool mi_bitmap_unclaim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+
+// Set `count` bits at `bitmap_idx` to 1 atomically
+// Returns `true` if all `count` bits were 0 previously. `any_zero` is `true` if there was at least one zero bit.
+bool _mi_bitmap_claim(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* any_zero);
+
+bool _mi_bitmap_is_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+bool _mi_bitmap_is_any_claimed(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+
+
+//--------------------------------------------------------------------------
+// the `_across` functions work on bitmaps where sequences can cross over
+// between the fields. This is used in arena allocation
+//--------------------------------------------------------------------------
+
+// Find `count` bits of zeros and set them to 1 atomically; returns `true` on success.
+// Starts at idx, and wraps around to search in all `bitmap_fields` fields.
+bool _mi_bitmap_try_find_from_claim_across(mi_bitmap_t bitmap, const size_t bitmap_fields, const size_t start_field_idx, const size_t count, mi_bitmap_index_t* bitmap_idx);
+
+// Set `count` bits at `bitmap_idx` to 0 atomically
+// Returns `true` if all `count` bits were 1 previously.
+bool _mi_bitmap_unclaim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+
+// Set `count` bits at `bitmap_idx` to 1 atomically
+// Returns `true` if all `count` bits were 0 previously. `any_zero` is `true` if there was at least one zero bit.
+bool _mi_bitmap_claim_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx, bool* pany_zero);
+
+bool _mi_bitmap_is_claimed_across(mi_bitmap_t bitmap, size_t bitmap_fields, size_t count, mi_bitmap_index_t bitmap_idx);
+
+#endif

src/region.c

@@ -37,7 +37,7 @@ Possible issues:
 
 #include <string.h>  // memset
 
-#include "bitmap.inc.c"
+#include "bitmap.h"
 
 // Internal raw OS interface
 size_t  _mi_os_large_page_size();
@@ -200,7 +200,7 @@ static bool mi_region_try_alloc_os(size_t blocks, bool commit, bool allow_large,
   mi_atomic_store_release(&r->commit, (region_commit ? MI_BITMAP_FIELD_FULL : 0));
   mi_atomic_store_release(&r->reset, (uintptr_t)0);
   *bit_idx = 0;
-  mi_bitmap_claim(&r->in_use, 1, blocks, *bit_idx, NULL);
+  _mi_bitmap_claim(&r->in_use, 1, blocks, *bit_idx, NULL);
   mi_atomic_store_ptr_release(void,&r->start, start);
 
   // and share it 
@@ -248,7 +248,7 @@ static bool mi_region_try_claim(int numa_node, size_t blocks, bool allow_large,
     // if this region suits our demand (numa node matches, large OS page matches)
     if (mi_region_is_suitable(r, numa_node, allow_large)) {
       // then try to atomically claim a segment(s) in this region
-      if (mi_bitmap_try_find_claim_field(&r->in_use, 0, blocks, bit_idx)) {
+      if (_mi_bitmap_try_find_claim_field(&r->in_use, 0, blocks, bit_idx)) {
         tld->region_idx = idx;    // remember the last found position
         *region = r;
         return true;
@@ -277,7 +277,7 @@ static void* mi_region_try_alloc(size_t blocks, bool* commit, bool* is_large, bo
   // ------------------------------------------------
   // found a region and claimed `blocks` at `bit_idx`, initialize them now
   mi_assert_internal(region != NULL);
-  mi_assert_internal(mi_bitmap_is_claimed(&region->in_use, 1, blocks, bit_idx));
+  mi_assert_internal(_mi_bitmap_is_claimed(&region->in_use, 1, blocks, bit_idx));
 
   mi_region_info_t info;
   info.value = mi_atomic_load_acquire(&region->info);
@@ -285,7 +285,7 @@ static void* mi_region_try_alloc(size_t blocks, bool* commit, bool* is_large, bo
   mi_assert_internal(!(info.x.is_large && !*is_large));
   mi_assert_internal(start != NULL);
 
-  *is_zero = mi_bitmap_claim(&region->dirty, 1, blocks, bit_idx, NULL);  
+  *is_zero = _mi_bitmap_claim(&region->dirty, 1, blocks, bit_idx, NULL);  
   *is_large = info.x.is_large;
   *memid = mi_memid_create(region, bit_idx);
   void* p = start + (mi_bitmap_index_bit_in_field(bit_idx) * MI_SEGMENT_SIZE);
@@ -294,7 +294,7 @@ static void* mi_region_try_alloc(size_t blocks, bool* commit, bool* is_large, bo
   if (*commit) {
     // ensure commit
     bool any_uncommitted;
-    mi_bitmap_claim(&region->commit, 1, blocks, bit_idx, &any_uncommitted);
+    _mi_bitmap_claim(&region->commit, 1, blocks, bit_idx, &any_uncommitted);
     if (any_uncommitted) {
       mi_assert_internal(!info.x.is_large);
       bool commit_zero;
@@ -304,12 +304,12 @@ static void* mi_region_try_alloc(size_t blocks, bool* commit, bool* is_large, bo
   }
   else {
     // no need to commit, but check if already fully committed
-    *commit = mi_bitmap_is_claimed(&region->commit, 1, blocks, bit_idx);
+    *commit = _mi_bitmap_is_claimed(&region->commit, 1, blocks, bit_idx);
   }  
-  mi_assert_internal(!*commit || mi_bitmap_is_claimed(&region->commit, 1, blocks, bit_idx));
+  mi_assert_internal(!*commit || _mi_bitmap_is_claimed(&region->commit, 1, blocks, bit_idx));
 
   // unreset reset blocks
-  if (mi_bitmap_is_any_claimed(&region->reset, 1, blocks, bit_idx)) {
+  if (_mi_bitmap_is_any_claimed(&region->reset, 1, blocks, bit_idx)) {
     // some blocks are still reset
     mi_assert_internal(!info.x.is_large);
     mi_assert_internal(!mi_option_is_enabled(mi_option_eager_commit) || *commit || mi_option_get(mi_option_eager_commit_delay) > 0); 
@@ -320,7 +320,7 @@ static void* mi_region_try_alloc(size_t blocks, bool* commit, bool* is_large, bo
       if (reset_zero) *is_zero = true;
     }
   }
-  mi_assert_internal(!mi_bitmap_is_any_claimed(&region->reset, 1, blocks, bit_idx));
+  mi_assert_internal(!_mi_bitmap_is_any_claimed(&region->reset, 1, blocks, bit_idx));
   
   #if (MI_DEBUG>=2)
   if (*commit) { ((uint8_t*)p)[0] = 0; }
@@ -409,12 +409,12 @@ void _mi_mem_free(void* p, size_t size, size_t id, bool full_commit, bool any_re
 
     // committed?
     if (full_commit && (size % MI_SEGMENT_SIZE) == 0) {
-      mi_bitmap_claim(&region->commit, 1, blocks, bit_idx, NULL);
+      _mi_bitmap_claim(&region->commit, 1, blocks, bit_idx, NULL);
     }
 
     if (any_reset) {
       // set the is_reset bits if any pages were reset
-      mi_bitmap_claim(&region->reset, 1, blocks, bit_idx, NULL);
+      _mi_bitmap_claim(&region->reset, 1, blocks, bit_idx, NULL);
     }
 
     // reset the blocks to reduce the working set.
@@ -423,7 +423,7 @@ void _mi_mem_free(void* p, size_t size, size_t id, bool full_commit, bool any_re
            mi_option_is_enabled(mi_option_reset_decommits))) // cannot reset halfway committed segments, use only `option_page_reset` instead            
     {
       bool any_unreset;
-      mi_bitmap_claim(&region->reset, 1, blocks, bit_idx, &any_unreset);
+      _mi_bitmap_claim(&region->reset, 1, blocks, bit_idx, &any_unreset);
       if (any_unreset) {
         _mi_abandoned_await_readers(); // ensure no more pending write (in case reset = decommit)
         _mi_mem_reset(p, blocks * MI_SEGMENT_SIZE, tld);

src/static.c

@@ -23,6 +23,7 @@ terms of the MIT license. A copy of the license can be found in the file
 #include "stats.c"
 #include "random.c"
 #include "os.c"
+#include "bitmap.c"
 #include "arena.c"
 #include "region.c"
 #include "segment.c"