+//===- llvm/unittest/Support/AllocatorTest.cpp - BumpPtrAllocator tests ---===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/Allocator.h"
+#include "gtest/gtest.h"
+#include <cstdlib>
+
+using namespace llvm;
+
+namespace {
+
+TEST(AllocatorTest, Basics) {
+ BumpPtrAllocator Alloc;
+ int *a = (int*)Alloc.Allocate(sizeof(int), 1);
+ int *b = (int*)Alloc.Allocate(sizeof(int) * 10, 1);
+ int *c = (int*)Alloc.Allocate(sizeof(int), 1);
+ *a = 1;
+ b[0] = 2;
+ b[9] = 2;
+ *c = 3;
+ EXPECT_EQ(1, *a);
+ EXPECT_EQ(2, b[0]);
+ EXPECT_EQ(2, b[9]);
+ EXPECT_EQ(3, *c);
+ EXPECT_EQ(1U, Alloc.GetNumSlabs());
+
+ BumpPtrAllocator Alloc2 = std::move(Alloc);
+ EXPECT_EQ(0U, Alloc.GetNumSlabs());
+ EXPECT_EQ(1U, Alloc2.GetNumSlabs());
+
+ // Make sure the old pointers still work. These are especially interesting
+ // under ASan or Valgrind.
+ EXPECT_EQ(1, *a);
+ EXPECT_EQ(2, b[0]);
+ EXPECT_EQ(2, b[9]);
+ EXPECT_EQ(3, *c);
+
+ Alloc = std::move(Alloc2);
+ EXPECT_EQ(0U, Alloc2.GetNumSlabs());
+ EXPECT_EQ(1U, Alloc.GetNumSlabs());
+}
+
+// Allocate enough bytes to create three slabs.
+TEST(AllocatorTest, ThreeSlabs) {
+ BumpPtrAllocator Alloc;
+ Alloc.Allocate(3000, 1);
+ EXPECT_EQ(1U, Alloc.GetNumSlabs());
+ Alloc.Allocate(3000, 1);
+ EXPECT_EQ(2U, Alloc.GetNumSlabs());
+ Alloc.Allocate(3000, 1);
+ EXPECT_EQ(3U, Alloc.GetNumSlabs());
+}
+
+// Allocate enough bytes to create two slabs, reset the allocator, and do it
+// again.
+TEST(AllocatorTest, TestReset) {
+ BumpPtrAllocator Alloc;
+
+ // Allocate something larger than the SizeThreshold=4096.
+ (void)Alloc.Allocate(5000, 1);
+ Alloc.Reset();
+ // Calling Reset should free all CustomSizedSlabs.
+ EXPECT_EQ(0u, Alloc.GetNumSlabs());
+
+ Alloc.Allocate(3000, 1);
+ EXPECT_EQ(1U, Alloc.GetNumSlabs());
+ Alloc.Allocate(3000, 1);
+ EXPECT_EQ(2U, Alloc.GetNumSlabs());
+ Alloc.Reset();
+ EXPECT_EQ(1U, Alloc.GetNumSlabs());
+ Alloc.Allocate(3000, 1);
+ EXPECT_EQ(1U, Alloc.GetNumSlabs());
+ Alloc.Allocate(3000, 1);
+ EXPECT_EQ(2U, Alloc.GetNumSlabs());
+}
+
+// Test some allocations at varying alignments.
+TEST(AllocatorTest, TestAlignment) {
+ BumpPtrAllocator Alloc;
+ uintptr_t a;
+ a = (uintptr_t)Alloc.Allocate(1, 2);
+ EXPECT_EQ(0U, a & 1);
+ a = (uintptr_t)Alloc.Allocate(1, 4);
+ EXPECT_EQ(0U, a & 3);
+ a = (uintptr_t)Alloc.Allocate(1, 8);
+ EXPECT_EQ(0U, a & 7);
+ a = (uintptr_t)Alloc.Allocate(1, 16);
+ EXPECT_EQ(0U, a & 15);
+ a = (uintptr_t)Alloc.Allocate(1, 32);
+ EXPECT_EQ(0U, a & 31);
+ a = (uintptr_t)Alloc.Allocate(1, 64);
+ EXPECT_EQ(0U, a & 63);
+ a = (uintptr_t)Alloc.Allocate(1, 128);
+ EXPECT_EQ(0U, a & 127);
+}
+
+// Test allocating just over the slab size. This tests a bug where before the
+// allocator incorrectly calculated the buffer end pointer.
+TEST(AllocatorTest, TestOverflow) {
+ BumpPtrAllocator Alloc;
+
+ // Fill the slab right up until the end pointer.
+ Alloc.Allocate(4096, 1);
+ EXPECT_EQ(1U, Alloc.GetNumSlabs());
+
+ // If we don't allocate a new slab, then we will have overflowed.
+ Alloc.Allocate(1, 1);
+ EXPECT_EQ(2U, Alloc.GetNumSlabs());
+}
+
+// Test allocating with a size larger than the initial slab size.
+TEST(AllocatorTest, TestSmallSlabSize) {
+ BumpPtrAllocator Alloc;
+
+ Alloc.Allocate(8000, 1);
+ EXPECT_EQ(1U, Alloc.GetNumSlabs());
+}
+
+// Test requesting alignment that goes past the end of the current slab.
+TEST(AllocatorTest, TestAlignmentPastSlab) {
+ BumpPtrAllocator Alloc;
+ Alloc.Allocate(4095, 1);
+
+ // Aligning the current slab pointer is likely to move it past the end of the
+ // slab, which would confuse any unsigned comparisons with the difference of
+ // the end pointer and the aligned pointer.
+ Alloc.Allocate(1024, 8192);
+
+ EXPECT_EQ(2U, Alloc.GetNumSlabs());
+}
+
+// Mock slab allocator that returns slabs aligned on 4096 bytes. There is no
+// easy portable way to do this, so this is kind of a hack.
+class MockSlabAllocator {
+ static size_t LastSlabSize;
+
+public:
+ ~MockSlabAllocator() { }
+
+ void *Allocate(size_t Size, size_t /*Alignment*/) {
+ // Allocate space for the alignment, the slab, and a void* that goes right
+ // before the slab.
+ size_t Alignment = 4096;
+ void *MemBase = malloc(Size + Alignment - 1 + sizeof(void*));
+
+ // Find the slab start.
+ void *Slab = (void *)alignAddr((char*)MemBase + sizeof(void *), Alignment);
+
+ // Hold a pointer to the base so we can free the whole malloced block.
+ ((void**)Slab)[-1] = MemBase;
+
+ LastSlabSize = Size;
+ return Slab;
+ }
+
+ void Deallocate(void *Slab, size_t Size) {
+ free(((void**)Slab)[-1]);
+ }
+
+ static size_t GetLastSlabSize() { return LastSlabSize; }
+};
+
+size_t MockSlabAllocator::LastSlabSize = 0;
+
+// Allocate a large-ish block with a really large alignment so that the
+// allocator will think that it has space, but after it does the alignment it
+// will not.
+TEST(AllocatorTest, TestBigAlignment) {
+ BumpPtrAllocatorImpl<MockSlabAllocator> Alloc;
+
+ // First allocate a tiny bit to ensure we have to re-align things.
+ (void)Alloc.Allocate(1, 1);
+
+ // Now the big chunk with a big alignment.
+ (void)Alloc.Allocate(3000, 2048);
+
+ // We test that the last slab size is not the default 4096 byte slab, but
+ // rather a custom sized slab that is larger.
+ EXPECT_GT(MockSlabAllocator::GetLastSlabSize(), 4096u);
+}
+
+} // anonymous namespace
projects / oota-llvm.git / blobdiff