[PATCH] D119951: [demangler] Fix build breakage

[Nathan Sidwell via Phabricator via llvm-commits]

urnathan updated this revision to Diff 409277.
urnathan edited the summary of this revision.

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D119951/new/

https://reviews.llvm.org/D119951

Files:
  libcxxabi/src/demangle/Utility.h
  llvm/include/llvm/Demangle/Utility.h


Index: llvm/include/llvm/Demangle/Utility.h
===================================================================
--- llvm/include/llvm/Demangle/Utility.h
+++ llvm/include/llvm/Demangle/Utility.h
@@ -37,10 +37,13 @@
   void grow(size_t N) {
     size_t Need = N + CurrentPosition;
     if (Need > BufferCapacity) {
-      // Avoid many reallocations during startup, with a bit of hysteresis.
-      constexpr size_t MinInitAlloc = 1024;
-      Need = std::max(Need, MinInitAlloc);
-      BufferCapacity = std::max(Need, BufferCapacity * 2);
+      // Reduce the number of reallocations, with a bit of hysteresis. The
+      // number here is chosen so the first allocation will more-than-likely not
+      // allocate more than 1K.
+      Need += 1024 - 32;
+      BufferCapacity *= 2;
+      if (BufferCapacity < Need)
+        BufferCapacity = Need;
       Buffer = static_cast<char *>(std::realloc(Buffer, BufferCapacity));
       if (Buffer == nullptr)
         std::terminate();
Index: libcxxabi/src/demangle/Utility.h
===================================================================
--- libcxxabi/src/demangle/Utility.h
+++ libcxxabi/src/demangle/Utility.h
@@ -17,7 +17,6 @@
 #define DEMANGLE_UTILITY_H
 
 #include "StringView.h"
-#include <algorithm>
 #include <array>
 #include <cstdint>
 #include <cstdlib>
@@ -38,10 +37,13 @@
   void grow(size_t N) {
     size_t Need = N + CurrentPosition;
     if (Need > BufferCapacity) {
-      // Avoid many reallocations during startup, with a bit of hysteresis.
-      constexpr size_t MinInitAlloc = 1024;
-      Need = std::max(Need, MinInitAlloc);
-      BufferCapacity = std::max(Need, BufferCapacity * 2);
+      // Reduce the number of reallocations, with a bit of hysteresis. The
+      // number here is chosen so the first allocation will more-than-likely not
+      // allocate more than 1K.
+      Need += 1024 - 32;
+      BufferCapacity *= 2;
+      if (BufferCapacity < Need)
+        BufferCapacity = Need;
       Buffer = static_cast<char *>(std::realloc(Buffer, BufferCapacity));
       if (Buffer == nullptr)
         std::terminate();


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D119951.409277.patch
Type: text/x-patch
Size: 2105 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20220216/19d23fde/attachment.bin>