Add m-esr52 at 52.6.0

1 files changed, 350 insertions, 0 deletions

diff --git a/js/src/jit/x86-shared/Assembler-x86-shared.cpp b/js/src/jit/x86-shared/Assembler-x86-shared.cpp
new file mode 100644
index 000000000..8d761c138
--- /dev/null
+++ b/js/src/jit/x86-shared/Assembler-x86-shared.cpp
@@ -0,0 +1,350 @@
+/* -*- 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 "gc/Marking.h"
+#include "jit/Disassembler.h"
+#include "jit/JitCompartment.h"
+#if defined(JS_CODEGEN_X86)
+# include "jit/x86/MacroAssembler-x86.h"
+#elif defined(JS_CODEGEN_X64)
+# include "jit/x64/MacroAssembler-x64.h"
+#else
+# error "Wrong architecture. Only x86 and x64 should build this file!"
+#endif
+
+#ifdef _MSC_VER
+# include <intrin.h> // for __cpuid
+# if defined(_M_X64) && (_MSC_FULL_VER >= 160040219)
+#  include <immintrin.h> // for _xgetbv
+# endif
+#endif
+
+using namespace js;
+using namespace js::jit;
+
+void
+AssemblerX86Shared::copyJumpRelocationTable(uint8_t* dest)
+{
+    if (jumpRelocations_.length())
+        memcpy(dest, jumpRelocations_.buffer(), jumpRelocations_.length());
+}
+
+void
+AssemblerX86Shared::copyDataRelocationTable(uint8_t* dest)
+{
+    if (dataRelocations_.length())
+        memcpy(dest, dataRelocations_.buffer(), dataRelocations_.length());
+}
+
+void
+AssemblerX86Shared::copyPreBarrierTable(uint8_t* dest)
+{
+    if (preBarriers_.length())
+        memcpy(dest, preBarriers_.buffer(), preBarriers_.length());
+}
+
+static void
+TraceDataRelocations(JSTracer* trc, uint8_t* buffer, CompactBufferReader& reader)
+{
+    while (reader.more()) {
+        size_t offset = reader.readUnsigned();
+        void* ptr = X86Encoding::GetPointer(buffer + offset);
+
+#ifdef JS_PUNBOX64
+        // All pointers on x64 will have the top bits cleared. If those bits
+        // are not cleared, this must be a Value.
+        uintptr_t word = reinterpret_cast<uintptr_t>(ptr);
+        if (word >> JSVAL_TAG_SHIFT) {
+            Value v = Value::fromRawBits(word);
+            TraceManuallyBarrieredEdge(trc, &v, "jit-masm-value");
+            if (word != v.asRawBits()) {
+                // Only update the code if the Value changed, because the code
+                // is not writable if we're not moving objects.
+                X86Encoding::SetPointer(buffer + offset, v.bitsAsPunboxPointer());
+            }
+            continue;
+        }
+#endif
+
+        // No barrier needed since these are constants.
+        gc::Cell* cellPtr = reinterpret_cast<gc::Cell*>(ptr);
+        TraceManuallyBarrieredGenericPointerEdge(trc, &cellPtr, "jit-masm-ptr");
+        if (cellPtr != ptr)
+            X86Encoding::SetPointer(buffer + offset, cellPtr);
+    }
+}
+
+
+void
+AssemblerX86Shared::TraceDataRelocations(JSTracer* trc, JitCode* code, CompactBufferReader& reader)
+{
+    ::TraceDataRelocations(trc, code->raw(), reader);
+}
+
+void
+AssemblerX86Shared::trace(JSTracer* trc)
+{
+    for (size_t i = 0; i < jumps_.length(); i++) {
+        RelativePatch& rp = jumps_[i];
+        if (rp.kind == Relocation::JITCODE) {
+            JitCode* code = JitCode::FromExecutable((uint8_t*)rp.target);
+            TraceManuallyBarrieredEdge(trc, &code, "masmrel32");
+            MOZ_ASSERT(code == JitCode::FromExecutable((uint8_t*)rp.target));
+        }
+    }
+    if (dataRelocations_.length()) {
+        CompactBufferReader reader(dataRelocations_);
+        ::TraceDataRelocations(trc, masm.data(), reader);
+    }
+}
+
+void
+AssemblerX86Shared::executableCopy(void* buffer)
+{
+    masm.executableCopy(buffer);
+
+    // Crash diagnostics for bug 1124397. Check the code buffer has not been
+    // poisoned with 0xE5 bytes.
+    static const size_t MinPoisoned = 16;
+    const uint8_t* bytes = (const uint8_t*)buffer;
+    size_t len = size();
+
+    for (size_t i = 0; i < len; i += MinPoisoned) {
+        if (bytes[i] != 0xE5)
+            continue;
+
+        size_t startOffset = i;
+        while (startOffset > 0 && bytes[startOffset - 1] == 0xE5)
+            startOffset--;
+
+        size_t endOffset = i;
+        while (endOffset + 1 < len && bytes[endOffset + 1] == 0xE5)
+            endOffset++;
+
+        if (endOffset - startOffset < MinPoisoned)
+            continue;
+
+        volatile uintptr_t dump[5];
+        blackbox = dump;
+        blackbox[0] = uintptr_t(0xABCD4321);
+        blackbox[1] = uintptr_t(len);
+        blackbox[2] = uintptr_t(startOffset);
+        blackbox[3] = uintptr_t(endOffset);
+        blackbox[4] = uintptr_t(0xFFFF8888);
+        MOZ_CRASH("Corrupt code buffer");
+    }
+}
+
+void
+AssemblerX86Shared::processCodeLabels(uint8_t* rawCode)
+{
+    for (size_t i = 0; i < codeLabels_.length(); i++) {
+        CodeLabel label = codeLabels_[i];
+        Bind(rawCode, label.patchAt(), rawCode + label.target()->offset());
+    }
+}
+
+AssemblerX86Shared::Condition
+AssemblerX86Shared::InvertCondition(Condition cond)
+{
+    switch (cond) {
+      case Zero:
+        return NonZero;
+      case NonZero:
+        return Zero;
+      case LessThan:
+        return GreaterThanOrEqual;
+      case LessThanOrEqual:
+        return GreaterThan;
+      case GreaterThan:
+        return LessThanOrEqual;
+      case GreaterThanOrEqual:
+        return LessThan;
+      case Above:
+        return BelowOrEqual;
+      case AboveOrEqual:
+        return Below;
+      case Below:
+        return AboveOrEqual;
+      case BelowOrEqual:
+        return Above;
+      default:
+        MOZ_CRASH("unexpected condition");
+    }
+}
+
+AssemblerX86Shared::Condition
+AssemblerX86Shared::UnsignedCondition(Condition cond)
+{
+    switch (cond) {
+      case Zero:
+      case NonZero:
+        return cond;
+      case LessThan:
+      case Below:
+        return Below;
+      case LessThanOrEqual:
+      case BelowOrEqual:
+        return BelowOrEqual;
+      case GreaterThan:
+      case Above:
+        return Above;
+      case AboveOrEqual:
+      case GreaterThanOrEqual:
+        return AboveOrEqual;
+      default:
+        MOZ_CRASH("unexpected condition");
+    }
+}
+
+AssemblerX86Shared::Condition
+AssemblerX86Shared::ConditionWithoutEqual(Condition cond)
+{
+    switch (cond) {
+      case LessThan:
+      case LessThanOrEqual:
+          return LessThan;
+      case Below:
+      case BelowOrEqual:
+        return Below;
+      case GreaterThan:
+      case GreaterThanOrEqual:
+        return GreaterThan;
+      case Above:
+      case AboveOrEqual:
+        return Above;
+      default:
+        MOZ_CRASH("unexpected condition");
+    }
+}
+
+void
+AssemblerX86Shared::verifyHeapAccessDisassembly(uint32_t begin, uint32_t end,
+                                                const Disassembler::HeapAccess& heapAccess)
+{
+#ifdef DEBUG
+    if (masm.oom())
+        return;
+    Disassembler::VerifyHeapAccess(masm.data() + begin, masm.data() + end, heapAccess);
+#endif
+}
+
+CPUInfo::SSEVersion CPUInfo::maxSSEVersion = UnknownSSE;
+CPUInfo::SSEVersion CPUInfo::maxEnabledSSEVersion = UnknownSSE;
+bool CPUInfo::avxPresent = false;
+bool CPUInfo::avxEnabled = false;
+bool CPUInfo::popcntPresent = false;
+bool CPUInfo::needAmdBugWorkaround = false;
+
+static uintptr_t
+ReadXGETBV()
+{
+    // We use a variety of low-level mechanisms to get at the xgetbv
+    // instruction, including spelling out the xgetbv instruction as bytes,
+    // because older compilers and assemblers may not recognize the instruction
+    // by name.
+    size_t xcr0EAX = 0;
+#if defined(_XCR_XFEATURE_ENABLED_MASK)
+    xcr0EAX = _xgetbv(_XCR_XFEATURE_ENABLED_MASK);
+#elif defined(__GNUC__)
+    // xgetbv returns its results in %eax and %edx, and for our purposes here,
+    // we're only interested in the %eax value.
+    asm(".byte 0x0f, 0x01, 0xd0" : "=a"(xcr0EAX) : "c"(0) : "%edx");
+#elif defined(_MSC_VER) && defined(_M_IX86)
+    __asm {
+        xor ecx, ecx
+        _asm _emit 0x0f _asm _emit 0x01 _asm _emit 0xd0
+        mov xcr0EAX, eax
+    }
+#endif
+    return xcr0EAX;
+}
+
+void
+CPUInfo::SetSSEVersion()
+{
+    int flagsEAX = 0;
+    int flagsECX = 0;
+    int flagsEDX = 0;
+
+#ifdef _MSC_VER
+    int cpuinfo[4];
+    __cpuid(cpuinfo, 1);
+    flagsEAX = cpuinfo[0];
+    flagsECX = cpuinfo[2];
+    flagsEDX = cpuinfo[3];
+#elif defined(__GNUC__)
+# ifdef JS_CODEGEN_X64
+    asm (
+         "movl $0x1, %%eax;"
+         "cpuid;"
+         : "=a" (flagsEAX), "=c" (flagsECX), "=d" (flagsEDX)
+         :
+         : "%ebx"
+         );
+# else
+    // On x86, preserve ebx. The compiler needs it for PIC mode.
+    // Some older processors don't fill the ecx register with cpuid, so clobber
+    // it before calling cpuid, so that there's no risk of picking random bits
+    // indicating SSE3/SSE4 are present.
+    asm (
+         "xor %%ecx, %%ecx;"
+         "movl $0x1, %%eax;"
+         "pushl %%ebx;"
+         "cpuid;"
+         "popl %%ebx;"
+         : "=a" (flagsEAX), "=c" (flagsECX), "=d" (flagsEDX)
+         :
+         :
+         );
+# endif
+#else
+# error "Unsupported compiler"
+#endif
+
+    static const int SSEBit = 1 << 25;
+    static const int SSE2Bit = 1 << 26;
+    static const int SSE3Bit = 1 << 0;
+    static const int SSSE3Bit = 1 << 9;
+    static const int SSE41Bit = 1 << 19;
+    static const int SSE42Bit = 1 << 20;
+
+    if (flagsECX & SSE42Bit)      maxSSEVersion = SSE4_2;
+    else if (flagsECX & SSE41Bit) maxSSEVersion = SSE4_1;
+    else if (flagsECX & SSSE3Bit) maxSSEVersion = SSSE3;
+    else if (flagsECX & SSE3Bit)  maxSSEVersion = SSE3;
+    else if (flagsEDX & SSE2Bit)  maxSSEVersion = SSE2;
+    else if (flagsEDX & SSEBit)   maxSSEVersion = SSE;
+    else                          maxSSEVersion = NoSSE;
+
+    if (maxEnabledSSEVersion != UnknownSSE)
+        maxSSEVersion = Min(maxSSEVersion, maxEnabledSSEVersion);
+
+    static const int AVXBit = 1 << 28;
+    static const int XSAVEBit = 1 << 27;
+    avxPresent = (flagsECX & AVXBit) && (flagsECX & XSAVEBit) && avxEnabled;
+
+    // If the hardware supports AVX, check whether the OS supports it too.
+    if (avxPresent) {
+        size_t xcr0EAX = ReadXGETBV();
+        static const int xcr0SSEBit = 1 << 1;
+        static const int xcr0AVXBit = 1 << 2;
+        avxPresent = (xcr0EAX & xcr0SSEBit) && (xcr0EAX & xcr0AVXBit);
+    }
+
+    static const int POPCNTBit = 1 << 23;
+
+    popcntPresent = (flagsECX & POPCNTBit);
+
+    // Check if we need to work around an AMD CPU bug (see bug 1281759).
+    // We check for family 20 models 0-2. Intel doesn't use family 20 at
+    // this point, so this should only match AMD CPUs.
+    unsigned family = ((flagsEAX >> 20) & 0xff) + ((flagsEAX >> 8) & 0xf);
+    unsigned model = (((flagsEAX >> 16) & 0xf) << 4) + ((flagsEAX >> 4) & 0xf);
+    needAmdBugWorkaround = (family == 20 && model <= 2);
+}
+
+volatile uintptr_t* blackbox = nullptr;