Add m-esr52 at 52.6.0

1 files changed, 383 insertions, 0 deletions

diff --git a/js/src/jsapi-tests/testGCAllocator.cpp b/js/src/jsapi-tests/testGCAllocator.cpp
new file mode 100644
index 000000000..2c5c58a29
--- /dev/null
+++ b/js/src/jsapi-tests/testGCAllocator.cpp
@@ -0,0 +1,383 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+* vim: set ts=8 sts=4 et sw=4 tw=99:
+*/
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <cstdlib>
+
+#include "gc/GCInternals.h"
+#include "gc/Memory.h"
+#include "jsapi-tests/tests.h"
+
+#if defined(XP_WIN)
+#include "jswin.h"
+#include <psapi.h>
+#elif defined(SOLARIS)
+// This test doesn't apply to Solaris.
+#elif defined(XP_UNIX)
+#include <algorithm>
+#include <errno.h>
+#include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+#else
+#error "Memory mapping functions are not defined for your OS."
+#endif
+
+BEGIN_TEST(testGCAllocator)
+{
+    size_t PageSize = 0;
+#if defined(XP_WIN)
+#  if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
+    SYSTEM_INFO sysinfo;
+    GetSystemInfo(&sysinfo);
+    PageSize = sysinfo.dwPageSize;
+#  else // Various APIs are unavailable. This test is disabled.
+    return true;
+#  endif
+#elif defined(SOLARIS)
+    return true;
+#elif defined(XP_UNIX)
+    PageSize = size_t(sysconf(_SC_PAGESIZE));
+#else
+    return true;
+#endif
+
+    /* Finish any ongoing background free activity. */
+    js::gc::FinishGC(cx);
+
+    bool growUp;
+    CHECK(addressesGrowUp(&growUp));
+
+    if (growUp)
+        return testGCAllocatorUp(PageSize);
+    return testGCAllocatorDown(PageSize);
+}
+
+static const size_t Chunk = 512 * 1024;
+static const size_t Alignment = 2 * Chunk;
+static const int MaxTempChunks = 4096;
+static const size_t StagingSize = 16 * Chunk;
+
+bool
+addressesGrowUp(bool* resultOut)
+{
+    /*
+     * Try to detect whether the OS allocates memory in increasing or decreasing
+     * address order by making several allocations and comparing the addresses.
+     */
+
+    static const unsigned ChunksToTest = 20;
+    static const int ThresholdCount = 15;
+
+    void* chunks[ChunksToTest];
+    for (unsigned i = 0; i < ChunksToTest; i++) {
+        chunks[i] = mapMemory(2 * Chunk);
+        CHECK(chunks[i]);
+    }
+
+    int upCount = 0;
+    int downCount = 0;
+
+    for (unsigned i = 0; i < ChunksToTest - 1; i++) {
+        if (chunks[i] < chunks[i + 1])
+            upCount++;
+        else
+            downCount++;
+    }
+
+    for (unsigned i = 0; i < ChunksToTest; i++)
+        unmapPages(chunks[i], 2 * Chunk);
+
+    /* Check results were mostly consistent. */
+    CHECK(abs(upCount - downCount) >= ThresholdCount);
+
+    *resultOut = upCount > downCount;
+
+    return true;
+}
+
+size_t
+offsetFromAligned(void* p)
+{
+    return uintptr_t(p) % Alignment;
+}
+
+enum AllocType {
+   UseNormalAllocator,
+   UseLastDitchAllocator
+};
+
+bool
+testGCAllocatorUp(const size_t PageSize)
+{
+    const size_t UnalignedSize = StagingSize + Alignment - PageSize;
+    void* chunkPool[MaxTempChunks];
+    // Allocate a contiguous chunk that we can partition for testing.
+    void* stagingArea = mapMemory(UnalignedSize);
+    if (!stagingArea)
+        return false;
+    // Ensure that the staging area is aligned.
+    unmapPages(stagingArea, UnalignedSize);
+    if (offsetFromAligned(stagingArea)) {
+        const size_t Offset = offsetFromAligned(stagingArea);
+        // Place the area at the lowest aligned address.
+        stagingArea = (void*)(uintptr_t(stagingArea) + (Alignment - Offset));
+    }
+    mapMemoryAt(stagingArea, StagingSize);
+    // Make sure there are no available chunks below the staging area.
+    int tempChunks;
+    if (!fillSpaceBeforeStagingArea(tempChunks, stagingArea, chunkPool, false))
+        return false;
+    // Unmap the staging area so we can set it up for testing.
+    unmapPages(stagingArea, StagingSize);
+    // Check that the first chunk is used if it is aligned.
+    CHECK(positionIsCorrect("xxooxxx---------", stagingArea, chunkPool, tempChunks));
+    // Check that the first chunk is used if it can be aligned.
+    CHECK(positionIsCorrect("x-ooxxx---------", stagingArea, chunkPool, tempChunks));
+    // Check that an aligned chunk after a single unalignable chunk is used.
+    CHECK(positionIsCorrect("x--xooxxx-------", stagingArea, chunkPool, tempChunks));
+    // Check that we fall back to the slow path after two unalignable chunks.
+    CHECK(positionIsCorrect("x--xx--xoo--xxx-", stagingArea, chunkPool, tempChunks));
+    // Check that we also fall back after an unalignable and an alignable chunk.
+    CHECK(positionIsCorrect("x--xx---x-oo--x-", stagingArea, chunkPool, tempChunks));
+    // Check that the last ditch allocator works as expected.
+    CHECK(positionIsCorrect("x--xx--xx-oox---", stagingArea, chunkPool, tempChunks,
+                            UseLastDitchAllocator));
+
+    // Clean up.
+    while (--tempChunks >= 0)
+        unmapPages(chunkPool[tempChunks], 2 * Chunk);
+    return true;
+}
+
+bool
+testGCAllocatorDown(const size_t PageSize)
+{
+    const size_t UnalignedSize = StagingSize + Alignment - PageSize;
+    void* chunkPool[MaxTempChunks];
+    // Allocate a contiguous chunk that we can partition for testing.
+    void* stagingArea = mapMemory(UnalignedSize);
+    if (!stagingArea)
+        return false;
+    // Ensure that the staging area is aligned.
+    unmapPages(stagingArea, UnalignedSize);
+    if (offsetFromAligned(stagingArea)) {
+        void* stagingEnd = (void*)(uintptr_t(stagingArea) + UnalignedSize);
+        const size_t Offset = offsetFromAligned(stagingEnd);
+        // Place the area at the highest aligned address.
+        stagingArea = (void*)(uintptr_t(stagingEnd) - Offset - StagingSize);
+    }
+    mapMemoryAt(stagingArea, StagingSize);
+    // Make sure there are no available chunks above the staging area.
+    int tempChunks;
+    if (!fillSpaceBeforeStagingArea(tempChunks, stagingArea, chunkPool, true))
+        return false;
+    // Unmap the staging area so we can set it up for testing.
+    unmapPages(stagingArea, StagingSize);
+    // Check that the first chunk is used if it is aligned.
+    CHECK(positionIsCorrect("---------xxxooxx", stagingArea, chunkPool, tempChunks));
+    // Check that the first chunk is used if it can be aligned.
+    CHECK(positionIsCorrect("---------xxxoo-x", stagingArea, chunkPool, tempChunks));
+    // Check that an aligned chunk after a single unalignable chunk is used.
+    CHECK(positionIsCorrect("-------xxxoox--x", stagingArea, chunkPool, tempChunks));
+    // Check that we fall back to the slow path after two unalignable chunks.
+    CHECK(positionIsCorrect("-xxx--oox--xx--x", stagingArea, chunkPool, tempChunks));
+    // Check that we also fall back after an unalignable and an alignable chunk.
+    CHECK(positionIsCorrect("-x--oo-x---xx--x", stagingArea, chunkPool, tempChunks));
+    // Check that the last ditch allocator works as expected.
+    CHECK(positionIsCorrect("---xoo-xx--xx--x", stagingArea, chunkPool, tempChunks,
+                            UseLastDitchAllocator));
+
+    // Clean up.
+    while (--tempChunks >= 0)
+        unmapPages(chunkPool[tempChunks], 2 * Chunk);
+    return true;
+}
+
+bool
+fillSpaceBeforeStagingArea(int& tempChunks, void* stagingArea,
+                           void** chunkPool, bool addressesGrowDown)
+{
+    // Make sure there are no available chunks before the staging area.
+    tempChunks = 0;
+    chunkPool[tempChunks++] = mapMemory(2 * Chunk);
+    while (tempChunks < MaxTempChunks && chunkPool[tempChunks - 1] &&
+           (chunkPool[tempChunks - 1] < stagingArea) ^ addressesGrowDown) {
+        chunkPool[tempChunks++] = mapMemory(2 * Chunk);
+        if (!chunkPool[tempChunks - 1])
+            break; // We already have our staging area, so OOM here is okay.
+        if ((chunkPool[tempChunks - 1] < chunkPool[tempChunks - 2]) ^ addressesGrowDown)
+            break; // The address growth direction is inconsistent!
+    }
+    // OOM also means success in this case.
+    if (!chunkPool[tempChunks - 1]) {
+        --tempChunks;
+        return true;
+    }
+    // Bail if we can't guarantee the right address space layout.
+    if ((chunkPool[tempChunks - 1] < stagingArea) ^ addressesGrowDown || (tempChunks > 1 &&
+            (chunkPool[tempChunks - 1] < chunkPool[tempChunks - 2]) ^ addressesGrowDown))
+    {
+        while (--tempChunks >= 0)
+            unmapPages(chunkPool[tempChunks], 2 * Chunk);
+        unmapPages(stagingArea, StagingSize);
+        return false;
+    }
+    return true;
+}
+
+bool
+positionIsCorrect(const char* str, void* base, void** chunkPool, int tempChunks,
+                  AllocType allocator = UseNormalAllocator)
+{
+    // str represents a region of memory, with each character representing a
+    // region of Chunk bytes. str should contain only x, o and -, where
+    // x = mapped by the test to set up the initial conditions,
+    // o = mapped by the GC allocator, and
+    // - = unmapped.
+    // base should point to a region of contiguous free memory
+    // large enough to hold strlen(str) chunks of Chunk bytes.
+    int len = strlen(str);
+    int i;
+    // Find the index of the desired address.
+    for (i = 0; i < len && str[i] != 'o'; ++i);
+    void* desired = (void*)(uintptr_t(base) + i * Chunk);
+    // Map the regions indicated by str.
+    for (i = 0; i < len; ++i) {
+        if (str[i] == 'x')
+            mapMemoryAt((void*)(uintptr_t(base) +  i * Chunk), Chunk);
+    }
+    // Allocate using the GC's allocator.
+    void* result;
+    if (allocator == UseNormalAllocator)
+        result = js::gc::MapAlignedPages(2 * Chunk, Alignment);
+    else
+        result = js::gc::TestMapAlignedPagesLastDitch(2 * Chunk, Alignment);
+    // Clean up the mapped regions.
+    if (result)
+        js::gc::UnmapPages(result, 2 * Chunk);
+    for (--i; i >= 0; --i) {
+        if (str[i] == 'x')
+            js::gc::UnmapPages((void*)(uintptr_t(base) +  i * Chunk), Chunk);
+    }
+    // CHECK returns, so clean up on failure.
+    if (result != desired) {
+        while (--tempChunks >= 0)
+            js::gc::UnmapPages(chunkPool[tempChunks], 2 * Chunk);
+    }
+    return result == desired;
+}
+
+#if defined(XP_WIN)
+#  if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
+
+void*
+mapMemoryAt(void* desired, size_t length)
+{
+    return VirtualAlloc(desired, length, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
+}
+
+void*
+mapMemory(size_t length)
+{
+    return VirtualAlloc(nullptr, length, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
+}
+
+void
+unmapPages(void* p, size_t size)
+{
+    MOZ_ALWAYS_TRUE(VirtualFree(p, 0, MEM_RELEASE));
+}
+
+#  else // Various APIs are unavailable. This test is disabled.
+
+void* mapMemoryAt(void* desired, size_t length) { return nullptr; }
+void* mapMemory(size_t length) { return nullptr; }
+void unmapPages(void* p, size_t size) { }
+
+#  endif
+#elif defined(SOLARIS) // This test doesn't apply to Solaris.
+
+void* mapMemoryAt(void* desired, size_t length) { return nullptr; }
+void* mapMemory(size_t length) { return nullptr; }
+void unmapPages(void* p, size_t size) { }
+
+#elif defined(XP_UNIX)
+
+void*
+mapMemoryAt(void* desired, size_t length)
+{
+#if defined(__ia64__) || (defined(__sparc64__) && defined(__NetBSD__)) || defined(__aarch64__)
+    MOZ_RELEASE_ASSERT(0xffff800000000000ULL & (uintptr_t(desired) + length - 1) == 0);
+#endif
+    void* region = mmap(desired, length, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+    if (region == MAP_FAILED)
+        return nullptr;
+    if (region != desired) {
+        if (munmap(region, length))
+            MOZ_RELEASE_ASSERT(errno == ENOMEM);
+        return nullptr;
+    }
+    return region;
+}
+
+void*
+mapMemory(size_t length)
+{
+    int prot = PROT_READ | PROT_WRITE;
+    int flags = MAP_PRIVATE | MAP_ANON;
+    int fd = -1;
+    off_t offset = 0;
+    // The test code must be aligned with the implementation in gc/Memory.cpp.
+#if defined(__ia64__) || (defined(__sparc64__) && defined(__NetBSD__))
+    void* region = mmap((void*)0x0000070000000000, length, prot, flags, fd, offset);
+    if (region == MAP_FAILED)
+        return nullptr;
+    if ((uintptr_t(region) + (length - 1)) & 0xffff800000000000) {
+        if (munmap(region, length))
+            MOZ_RELEASE_ASSERT(errno == ENOMEM);
+        return nullptr;
+    }
+    return region;
+#elif defined(__aarch64__)
+    const uintptr_t start = UINT64_C(0x0000070000000000);
+    const uintptr_t end   = UINT64_C(0x0000800000000000);
+    const uintptr_t step  = js::gc::ChunkSize;
+    uintptr_t hint;
+    void* region = MAP_FAILED;
+    for (hint = start; region == MAP_FAILED && hint + length <= end; hint += step) {
+        region = mmap((void*)hint, length, prot, flags, fd, offset);
+        if (region != MAP_FAILED) {
+            if ((uintptr_t(region) + (length - 1)) & 0xffff800000000000) {
+                if (munmap(region, length)) {
+                    MOZ_RELEASE_ASSERT(errno == ENOMEM);
+                }
+                region = MAP_FAILED;
+            }
+        }
+    }
+    return region == MAP_FAILED ? nullptr : region;
+#else
+    void* region = mmap(nullptr, length, prot, flags, fd, offset);
+    if (region == MAP_FAILED)
+        return nullptr;
+    return region;
+#endif
+}
+
+void
+unmapPages(void* p, size_t size)
+{
+    if (munmap(p, size))
+        MOZ_RELEASE_ASSERT(errno == ENOMEM);
+}
+
+#else // !defined(XP_WIN) && !defined(SOLARIS) && !defined(XP_UNIX)
+#error "Memory mapping functions are not defined for your OS."
+#endif
+END_TEST(testGCAllocator)