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 // Check that no bytes are wasted.
18 static_assert(sizeof(SmallVector<void *, 1>) ==
19                   sizeof(unsigned) * 2 + sizeof(void *) * 2,
20               "wasted space in SmallVector size 1; missing EBO?");
21 
22 /// grow_pod - This is an implementation of the grow() method which only works
23 /// on POD-like datatypes and is out of line to reduce code duplication.
24 void SmallVectorBase::grow_pod(void *FirstEl, size_t MinCapacity,
25                                size_t TSize) {
26   // Ensure we can fit the new capacity in 32 bits.
27   if (MinCapacity > UINT32_MAX)
28     report_bad_alloc_error("SmallVector capacity overflow during allocation");
29 
30   size_t NewCapacity = 2 * capacity() + 1; // Always grow.
31   NewCapacity =
32       std::min(std::max(NewCapacity, MinCapacity), size_t(UINT32_MAX));
33 
34   void *NewElts;
35   if (BeginX == FirstEl) {
36     NewElts = safe_malloc(NewCapacity * TSize);
37 
38     // Copy the elements over.  No need to run dtors on PODs.
39     memcpy(NewElts, this->BeginX, size() * TSize);
40   } else {
41     // If this wasn't grown from the inline copy, grow the allocated space.
42     NewElts = safe_realloc(this->BeginX, NewCapacity * TSize);
43   }
44 
45   this->BeginX = NewElts;
46   this->Capacity = NewCapacity;
47 }
48