v8/test/unittests/code-stub-assembler-unittest.cc
Jaroslav Sevcik f53dfd934d Replace array index masking with the poisoning approach.
The idea is to mark all the branches and loads participating in array
bounds checks, and let them contribute-to/use the poisoning register.
In the code, the marks for array indexing operations now contain
"Critical" in their name. By default (--untrusted-code-mitigations),
we only instrument the "critical" operations with poisoning.

With that in place, we also remove the array masking approach based
on arithmetic.

Since we do not propagate the poison through function calls,
we introduce a node for poisoning an index that is passed through
function call - the typical example is the bounds-checked index
that is passed to the CharCodeAt builtin.

Most of the code in this CL is threads through the three levels of
protection (safe, critical, unsafe) for loads, branches and flags.

Bug: chromium:798964

Change-Id: Ief68e2329528277b3ba9156115b2a6dcc540d52b
Reviewed-on: https://chromium-review.googlesource.com/995413
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52883}
2018-04-30 13:22:44 +00:00

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2.3 KiB
C++

// Copyright 2017 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "test/unittests/code-stub-assembler-unittest.h"
#include "src/code-factory.h"
#include "src/compiler/node.h"
#include "src/interface-descriptors.h"
#include "src/isolate.h"
#include "src/objects-inl.h"
#include "test/unittests/compiler/compiler-test-utils.h"
#include "test/unittests/compiler/node-test-utils.h"
using ::testing::_;
using v8::internal::compiler::Node;
namespace c = v8::internal::compiler;
namespace v8 {
namespace internal {
#ifdef ENABLE_VERIFY_CSA
#define IS_BITCAST_WORD_TO_TAGGED_SIGNED(x) IsBitcastWordToTaggedSigned(x)
#define IS_BITCAST_TAGGED_TO_WORD(x) IsBitcastTaggedToWord(x)
#else
#define IS_BITCAST_WORD_TO_TAGGED_SIGNED(x) (x)
#define IS_BITCAST_TAGGED_TO_WORD(x) (x)
#endif
CodeStubAssemblerTestState::CodeStubAssemblerTestState(
CodeStubAssemblerTest* test)
: compiler::CodeAssemblerState(
test->isolate(), test->zone(), VoidDescriptor(test->isolate()),
Code::STUB, "test", PoisoningMitigationLevel::kPoisonCriticalOnly) {}
TARGET_TEST_F(CodeStubAssemblerTest, SmiTag) {
CodeStubAssemblerTestState state(this);
CodeStubAssemblerForTest m(&state);
Node* value = m.Int32Constant(44);
EXPECT_THAT(m.SmiTag(value),
IS_BITCAST_WORD_TO_TAGGED_SIGNED(c::IsIntPtrConstant(
static_cast<intptr_t>(44) << (kSmiShiftSize + kSmiTagSize))));
EXPECT_THAT(m.SmiUntag(value),
c::IsIntPtrConstant(static_cast<intptr_t>(44) >>
(kSmiShiftSize + kSmiTagSize)));
}
TARGET_TEST_F(CodeStubAssemblerTest, IntPtrMax) {
CodeStubAssemblerTestState state(this);
CodeStubAssemblerForTest m(&state);
{
Node* a = m.IntPtrConstant(100);
Node* b = m.IntPtrConstant(1);
Node* z = m.IntPtrMax(a, b);
EXPECT_THAT(z, c::IsIntPtrConstant(100));
}
}
TARGET_TEST_F(CodeStubAssemblerTest, IntPtrMin) {
CodeStubAssemblerTestState state(this);
CodeStubAssemblerForTest m(&state);
{
Node* a = m.IntPtrConstant(100);
Node* b = m.IntPtrConstant(1);
Node* z = m.IntPtrMin(a, b);
EXPECT_THAT(z, c::IsIntPtrConstant(1));
}
}
} // namespace internal
} // namespace v8