lib/Support/SmallVector.cpp

   1 //===- llvm/ADT/SmallVector.cpp - 'Normally small' vectors ----------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the SmallVector class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/ADT/SmallVector.h"
  15 using namespace llvm;
  16
  17 /// grow_pod - This is an implementation of the grow() method which only works
  18 /// on POD-like datatypes and is out of line to reduce code duplication.
  19 void SmallVectorBase::grow_pod(size_t MinSizeInBytes, size_t TSize) {
  20   size_t CurSizeBytes = size_in_bytes();
  21   size_t NewCapacityInBytes = 2 * capacity_in_bytes() + TSize; // Always grow.
  22   if (NewCapacityInBytes < MinSizeInBytes)
  23     NewCapacityInBytes = MinSizeInBytes;
  24
  25   void *NewElts;
  26   if (this->isSmall()) {
  27     NewElts = malloc(NewCapacityInBytes);
  28
  29     // Copy the elements over.  No need to run dtors on PODs.
  30     memcpy(NewElts, this->BeginX, CurSizeBytes);
  31   } else {
  32     // If this wasn't grown from the inline copy, grow the allocated space.
  33     NewElts = realloc(this->BeginX, NewCapacityInBytes);
  34   }
  35
  36   this->EndX = (char*)NewElts+CurSizeBytes;
  37   this->BeginX = NewElts;
  38   this->CapacityX = (char*)this->BeginX + NewCapacityInBytes;
  39 }
  40