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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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,
// This program is used by the DMD xpcshell test. It is run under DMD and
// produces some output. The xpcshell test then post-processes and checks this
// output.
//
// Note that this file does not have "Test" or "test" in its name, because that
// will cause the build system to not record breakpad symbols for it, which
// will stop the post-processing (which includes stack fixing) from working
// correctly.
// This is required on some systems such as Fedora to allow
// building with -O0 together with --warnings-as-errors due to
// a check in /usr/include/features.h
#undef _FORTIFY_SOURCE
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include "mozilla/Assertions.h"
#include "mozilla/JSONWriter.h"
#include "mozilla/Sprintf.h"
#include "mozilla/UniquePtr.h"
#include "DMD.h"
using mozilla::MakeUnique;
using namespace mozilla::dmd;
DMDFuncs::Singleton DMDFuncs::sSingleton;
class FpWriteFunc final : public mozilla::JSONWriteFunc {
public:
explicit FpWriteFunc(const char* aFilename) {
mFp = fopen(aFilename, "w");
if (!mFp) {
fprintf(stderr, "SmokeDMD: can't create %s file: %s\n", aFilename,
strerror(errno));
exit(1);
}
}
~FpWriteFunc() { fclose(mFp); }
void Write(const mozilla::Span<const char>& aStr) final {
for (const char c : aStr) {
fputc(c, mFp);
}
}
private:
FILE* mFp;
};
// This stops otherwise-unused variables from being optimized away.
static void UseItOrLoseIt(void* aPtr, int aSeven) {
char buf[64];
int n = SprintfLiteral(buf, "%p\n", aPtr);
if (n == 20 + aSeven) {
fprintf(stderr, "well, that is surprising");
}
}
// This function checks that heap blocks that have the same stack trace but
// different (or no) reporters get aggregated separately.
void Foo(int aSeven) {
char* a[6];
for (int i = 0; i < aSeven - 1; i++) {
a[i] = (char*)malloc(128 - 16 * i);
UseItOrLoseIt(a[i], aSeven);
}
// Oddly, some versions of clang will cause identical stack traces to be
// generated for adjacent calls to Report(), which breaks the test. Inserting
// the UseItOrLoseIt() calls in between is enough to prevent this.
Report(a[2]); // reported
UseItOrLoseIt(a[2], aSeven);
for (int i = 0; i < aSeven - 5; i++) {
Report(a[i]); // reported
UseItOrLoseIt(a[i], aSeven);
}
UseItOrLoseIt(a[2], aSeven);
Report(a[3]); // reported
// a[4], a[5] unreported
}
void TestEmpty(const char* aTestName, const char* aMode) {
char filename[128];
SprintfLiteral(filename, "complete-%s-%s.json", aTestName, aMode);
auto f = MakeUnique<FpWriteFunc>(filename);
char options[128];
SprintfLiteral(options, "--mode=%s --stacks=full", aMode);
ResetEverything(options);
// Zero for everything.
Analyze(std::move(f));
}
void TestFull(const char* aTestName, int aNum, const char* aMode, int aSeven) {
char filename[128];
SprintfLiteral(filename, "complete-%s%d-%s.json", aTestName, aNum, aMode);
auto f = MakeUnique<FpWriteFunc>(filename);
// The --show-dump-stats=yes is there just to give that option some basic
// testing, e.g. ensure it doesn't crash. It's hard to test much beyond that.
char options[128];
SprintfLiteral(options, "--mode=%s --stacks=full --show-dump-stats=yes",
aMode);
ResetEverything(options);
// Analyze 1: 1 freed, 9 out of 10 unreported.
// Analyze 2: still present and unreported.
int i;
char* a = nullptr;
for (i = 0; i < aSeven + 3; i++) {
a = (char*)malloc(100);
UseItOrLoseIt(a, aSeven);
}
free(a);
// A no-op.
free(nullptr);
// Note: 16 bytes is the smallest requested size that gives consistent
// behaviour across all platforms with jemalloc.
// Analyze 1: reported.
// Analyze 2: thrice-reported.
char* a2 = (char*)malloc(16);
Report(a2);
// Analyze 1: reported.
// Analyze 2: reportedness carries over, due to ReportOnAlloc.
char* b = (char*)malloc(10);
ReportOnAlloc(b);
// ReportOnAlloc, then freed.
// Analyze 1: freed, irrelevant.
// Analyze 2: freed, irrelevant.
char* b2 = (char*)malloc(16);
ReportOnAlloc(b2);
free(b2);
// Analyze 1: reported 4 times.
// Analyze 2: freed, irrelevant.
char* c = (char*)calloc(10, 3);
Report(c);
for (int i = 0; i < aSeven - 4; i++) {
Report(c);
}
// Analyze 1: ignored.
// Analyze 2: irrelevant.
Report((void*)(intptr_t)i);
// jemalloc rounds this up to 8192.
// Analyze 1: reported.
// Analyze 2: freed.
char* e = (char*)malloc(4096);
e = (char*)realloc(e, 7169);
Report(e);
// First realloc is like malloc; second realloc is shrinking.
// Analyze 1: reported.
// Analyze 2: re-reported.
char* e2 = (char*)realloc(nullptr, 1024);
e2 = (char*)realloc(e2, 512);
Report(e2);
// First realloc is like malloc; second realloc creates a min-sized block.
// XXX: on Windows, second realloc frees the block.
// Analyze 1: reported.
// Analyze 2: freed, irrelevant.
char* e3 = (char*)realloc(nullptr, 1023);
// e3 = (char*) realloc(e3, 0);
MOZ_ASSERT(e3);
Report(e3);
// Analyze 1: freed, irrelevant.
// Analyze 2: freed, irrelevant.
char* f1 = (char*)malloc(64);
UseItOrLoseIt(f1, aSeven);
free(f1);
// Analyze 1: ignored.
// Analyze 2: irrelevant.
Report((void*)(intptr_t)0x0);
// Analyze 1: mixture of reported and unreported.
// Analyze 2: all unreported.
Foo(aSeven);
// Analyze 1: twice-reported.
// Analyze 2: twice-reported.
char* g1 = (char*)malloc(77);
ReportOnAlloc(g1);
ReportOnAlloc(g1);
// Analyze 1: mixture of reported and unreported.
// Analyze 2: all unreported.
// Nb: this Foo() call is deliberately not adjacent to the previous one. See
// the comment about adjacent calls in Foo() for more details.
Foo(aSeven);
// Analyze 1: twice-reported.
// Analyze 2: once-reported.
char* g2 = (char*)malloc(78);
Report(g2);
ReportOnAlloc(g2);
// Analyze 1: twice-reported.
// Analyze 2: once-reported.
char* g3 = (char*)malloc(79);
ReportOnAlloc(g3);
Report(g3);
// All the odd-ball ones.
// Analyze 1: all unreported.
// Analyze 2: all freed, irrelevant.
// XXX: no memalign on Mac
// void* w = memalign(64, 65); // rounds up to 128
// UseItOrLoseIt(w, aSeven);
// XXX: posix_memalign doesn't work on B2G
// void* x;
// posix_memalign(&y, 128, 129); // rounds up to 256
// UseItOrLoseIt(x, aSeven);
// XXX: valloc doesn't work on Windows.
// void* y = valloc(1); // rounds up to 4096
// UseItOrLoseIt(y, aSeven);
// XXX: C11 only
// void* z = aligned_alloc(64, 256);
// UseItOrLoseIt(z, aSeven);
if (aNum == 1) {
// Analyze 1.
Analyze(std::move(f));
}
ClearReports();
//---------
Report(a2);
Report(a2);
free(c);
free(e);
Report(e2);
free(e3);
// free(w);
// free(x);
// free(y);
// free(z);
// Do some allocations that will only show up in cumulative mode.
for (int i = 0; i < 100; i++) {
void* v = malloc(128);
UseItOrLoseIt(v, aSeven);
free(v);
}
if (aNum == 2) {
// Analyze 2.
Analyze(std::move(f));
}
}
void TestPartial(const char* aTestName, const char* aMode, int aSeven) {
char filename[128];
SprintfLiteral(filename, "complete-%s-%s.json", aTestName, aMode);
auto f = MakeUnique<FpWriteFunc>(filename);
char options[128];
SprintfLiteral(options, "--mode=%s", aMode);
ResetEverything(options);
int kTenThousand = aSeven + 9993;
char* s;
// The output of this function is deterministic but it relies on the
// probability and seeds given to the FastBernoulliTrial instance in
// ResetBernoulli(). If they change, the output will change too.
// Expected fraction with stacks: (1 - (1 - 0.003) ** 16) = 0.0469.
// So we expect about 0.0469 * 10000 == 469.
// We actually get 511.
for (int i = 0; i < kTenThousand; i++) {
s = (char*)malloc(16);
UseItOrLoseIt(s, aSeven);
}
// Expected fraction with stacks: (1 - (1 - 0.003) ** 128) = 0.3193.
// So we expect about 0.3193 * 10000 == 3193.
// We actually get 3136.
for (int i = 0; i < kTenThousand; i++) {
s = (char*)malloc(128);
UseItOrLoseIt(s, aSeven);
}
// Expected fraction with stacks: (1 - (1 - 0.003) ** 1024) = 0.9539.
// So we expect about 0.9539 * 10000 == 9539.
// We actually get 9531.
for (int i = 0; i < kTenThousand; i++) {
s = (char*)malloc(1024);
UseItOrLoseIt(s, aSeven);
}
Analyze(std::move(f));
}
void TestScan(int aSeven) {
auto f = MakeUnique<FpWriteFunc>("basic-scan.json");
ResetEverything("--mode=scan");
uintptr_t* p = (uintptr_t*)malloc(6 * sizeof(uintptr_t));
UseItOrLoseIt(p, aSeven);
// Hard-coded values checked by scan-test.py
p[0] = 0x123; // outside a block, small value
p[1] = 0x0; // null
p[2] = (uintptr_t)((uint8_t*)p - 1); // pointer outside a block, but nearby
p[3] = (uintptr_t)p; // pointer to start of a block
p[4] = (uintptr_t)((uint8_t*)p + 1); // pointer into a block
p[5] = 0x0; // trailing null
Analyze(std::move(f));
}
void RunTests() {
// This test relies on the compiler not doing various optimizations, such as
// eliding unused malloc() calls or unrolling loops with fixed iteration
// counts. So we compile it with -O0 (or equivalent), which probably prevents
// that. We also use the following variable for various loop iteration
// counts, just in case compilers might unroll very small loops even with
// -O0.
int seven = 7;
// Make sure that DMD is actually running; it is initialized on the first
// allocation.
int* x = (int*)malloc(100);
UseItOrLoseIt(x, seven);
MOZ_RELEASE_ASSERT(IsRunning());
// Please keep this in sync with run_test in test_dmd.js.
TestEmpty("empty", "live");
TestEmpty("empty", "dark-matter");
TestEmpty("empty", "cumulative");
TestFull("full", 1, "live", seven);
TestFull("full", 1, "dark-matter", seven);
TestFull("full", 2, "dark-matter", seven);
TestFull("full", 2, "cumulative", seven);
TestPartial("partial", "live", seven);
TestScan(seven);
}
int main() {
RunTests();
return 0;
}