Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 528 insertions, 0 deletions

diff --git a/js/src/wasm/WasmDebug.cpp b/js/src/wasm/WasmDebug.cpp
new file mode 100644
index 0000000000..66a59e826e
--- /dev/null
+++ b/js/src/wasm/WasmDebug.cpp
@@ -0,0 +1,528 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ *
+ * Copyright 2016 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "wasm/WasmDebug.h"
+
+#include "mozilla/BinarySearch.h"
+
+#include "debugger/Debugger.h"
+#include "ds/Sort.h"
+#include "jit/MacroAssembler.h"
+#include "wasm/WasmJS.h"
+#include "wasm/WasmStubs.h"
+#include "wasm/WasmValidate.h"
+
+#include "gc/GCContext-inl.h"
+#include "wasm/WasmInstance-inl.h"
+
+using namespace js;
+using namespace js::jit;
+using namespace js::wasm;
+
+using mozilla::BinarySearchIf;
+
+DebugState::DebugState(const Code& code, const Module& module)
+    : code_(&code),
+      module_(&module),
+      enterFrameTrapsEnabled_(false),
+      enterAndLeaveFrameTrapsCounter_(0) {
+  MOZ_RELEASE_ASSERT(code.metadata().debugEnabled);
+  MOZ_RELEASE_ASSERT(code.hasTier(Tier::Debug));
+}
+
+void DebugState::trace(JSTracer* trc) {
+  for (auto iter = breakpointSites_.iter(); !iter.done(); iter.next()) {
+    WasmBreakpointSite* site = iter.get().value();
+    site->trace(trc);
+  }
+}
+
+void DebugState::finalize(JS::GCContext* gcx) {
+  for (auto iter = breakpointSites_.iter(); !iter.done(); iter.next()) {
+    WasmBreakpointSite* site = iter.get().value();
+    site->delete_(gcx);
+  }
+}
+
+static const uint32_t DefaultBinarySourceColumnNumber = 1;
+
+static const CallSite* SlowCallSiteSearchByOffset(const MetadataTier& metadata,
+                                                  uint32_t offset) {
+  for (const CallSite& callSite : metadata.callSites) {
+    if (callSite.lineOrBytecode() == offset &&
+        callSite.kind() == CallSiteDesc::Breakpoint) {
+      return &callSite;
+    }
+  }
+  return nullptr;
+}
+
+bool DebugState::getLineOffsets(size_t lineno, Vector<uint32_t>* offsets) {
+  const CallSite* callsite =
+      SlowCallSiteSearchByOffset(metadata(Tier::Debug), lineno);
+  return !(callsite && !offsets->append(lineno));
+}
+
+bool DebugState::getAllColumnOffsets(Vector<ExprLoc>* offsets) {
+  for (const CallSite& callSite : metadata(Tier::Debug).callSites) {
+    if (callSite.kind() != CallSite::Breakpoint) {
+      continue;
+    }
+    uint32_t offset = callSite.lineOrBytecode();
+    if (!offsets->emplaceBack(offset, DefaultBinarySourceColumnNumber,
+                              offset)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool DebugState::getOffsetLocation(uint32_t offset, size_t* lineno,
+                                   size_t* column) {
+  if (!SlowCallSiteSearchByOffset(metadata(Tier::Debug), offset)) {
+    return false;
+  }
+  *lineno = offset;
+  *column = DefaultBinarySourceColumnNumber;
+  return true;
+}
+
+bool DebugState::stepModeEnabled(uint32_t funcIndex) const {
+  return stepperCounters_.lookup(funcIndex).found();
+}
+
+bool DebugState::incrementStepperCount(JSContext* cx, Instance* instance,
+                                       uint32_t funcIndex) {
+  StepperCounters::AddPtr p = stepperCounters_.lookupForAdd(funcIndex);
+  if (p) {
+    MOZ_ASSERT(p->value() > 0);
+    p->value()++;
+    return true;
+  }
+
+  if (!stepperCounters_.add(p, funcIndex, 1)) {
+    ReportOutOfMemory(cx);
+    return false;
+  }
+
+  enableDebuggingForFunction(instance, funcIndex);
+  enableDebugTrap(instance);
+
+  return true;
+}
+
+void DebugState::decrementStepperCount(JS::GCContext* gcx, Instance* instance,
+                                       uint32_t funcIndex) {
+  const CodeRange& codeRange =
+      codeRanges(Tier::Debug)[funcToCodeRangeIndex(funcIndex)];
+  MOZ_ASSERT(codeRange.isFunction());
+
+  MOZ_ASSERT(!stepperCounters_.empty());
+  StepperCounters::Ptr p = stepperCounters_.lookup(funcIndex);
+  MOZ_ASSERT(p);
+  if (--p->value()) {
+    return;
+  }
+
+  stepperCounters_.remove(p);
+
+  bool anyStepping = !stepperCounters_.empty();
+  bool anyBreakpoints = !breakpointSites_.empty();
+  bool anyEnterAndLeave = enterAndLeaveFrameTrapsCounter_ > 0;
+
+  bool keepDebugging = false;
+  for (const CallSite& callSite : callSites(Tier::Debug)) {
+    if (callSite.kind() != CallSite::Breakpoint) {
+      continue;
+    }
+    uint32_t offset = callSite.returnAddressOffset();
+    if (codeRange.begin() <= offset && offset <= codeRange.end()) {
+      keepDebugging = keepDebugging || breakpointSites_.has(offset);
+    }
+  }
+
+  if (!keepDebugging && !anyEnterAndLeave) {
+    disableDebuggingForFunction(instance, funcIndex);
+    if (!anyStepping && !anyBreakpoints) {
+      disableDebugTrap(instance);
+    }
+  }
+}
+
+bool DebugState::hasBreakpointTrapAtOffset(uint32_t offset) {
+  return SlowCallSiteSearchByOffset(metadata(Tier::Debug), offset);
+}
+
+void DebugState::toggleBreakpointTrap(JSRuntime* rt, Instance* instance,
+                                      uint32_t offset, bool enabled) {
+  const CallSite* callSite =
+      SlowCallSiteSearchByOffset(metadata(Tier::Debug), offset);
+  if (!callSite) {
+    return;
+  }
+  size_t debugTrapOffset = callSite->returnAddressOffset();
+
+  const ModuleSegment& codeSegment = code_->segment(Tier::Debug);
+  const CodeRange* codeRange =
+      code_->lookupFuncRange(codeSegment.base() + debugTrapOffset);
+  MOZ_ASSERT(codeRange);
+
+  uint32_t funcIndex = codeRange->funcIndex();
+  if (stepperCounters_.lookup(funcIndex)) {
+    return;  // no need to toggle when step mode is enabled
+  }
+
+  bool anyEnterAndLeave = enterAndLeaveFrameTrapsCounter_ > 0;
+  bool anyStepping = !stepperCounters_.empty();
+  bool anyBreakpoints = !breakpointSites_.empty();
+
+  if (enabled) {
+    enableDebuggingForFunction(instance, funcIndex);
+    enableDebugTrap(instance);
+  } else if (!anyEnterAndLeave) {
+    disableDebuggingForFunction(instance, funcIndex);
+    if (!anyStepping && !anyBreakpoints) {
+      disableDebugTrap(instance);
+    }
+  }
+}
+
+WasmBreakpointSite* DebugState::getBreakpointSite(uint32_t offset) const {
+  WasmBreakpointSiteMap::Ptr p = breakpointSites_.lookup(offset);
+  if (!p) {
+    return nullptr;
+  }
+
+  return p->value();
+}
+
+WasmBreakpointSite* DebugState::getOrCreateBreakpointSite(JSContext* cx,
+                                                          Instance* instance,
+                                                          uint32_t offset) {
+  WasmBreakpointSite* site;
+
+  WasmBreakpointSiteMap::AddPtr p = breakpointSites_.lookupForAdd(offset);
+  if (!p) {
+    site = cx->new_<WasmBreakpointSite>(instance->object(), offset);
+    if (!site) {
+      return nullptr;
+    }
+
+    if (!breakpointSites_.add(p, offset, site)) {
+      js_delete(site);
+      ReportOutOfMemory(cx);
+      return nullptr;
+    }
+
+    AddCellMemory(instance->object(), sizeof(WasmBreakpointSite),
+                  MemoryUse::BreakpointSite);
+
+    toggleBreakpointTrap(cx->runtime(), instance, offset, true);
+  } else {
+    site = p->value();
+  }
+  return site;
+}
+
+bool DebugState::hasBreakpointSite(uint32_t offset) {
+  return breakpointSites_.has(offset);
+}
+
+void DebugState::destroyBreakpointSite(JS::GCContext* gcx, Instance* instance,
+                                       uint32_t offset) {
+  WasmBreakpointSiteMap::Ptr p = breakpointSites_.lookup(offset);
+  MOZ_ASSERT(p);
+  gcx->delete_(instance->objectUnbarriered(), p->value(),
+               MemoryUse::BreakpointSite);
+  breakpointSites_.remove(p);
+  toggleBreakpointTrap(gcx->runtime(), instance, offset, false);
+}
+
+void DebugState::clearBreakpointsIn(JS::GCContext* gcx,
+                                    WasmInstanceObject* instance,
+                                    js::Debugger* dbg, JSObject* handler) {
+  MOZ_ASSERT(instance);
+
+  // Breakpoints hold wrappers in the instance's compartment for the handler.
+  // Make sure we don't try to search for the unwrapped handler.
+  MOZ_ASSERT_IF(handler, instance->compartment() == handler->compartment());
+
+  if (breakpointSites_.empty()) {
+    return;
+  }
+  for (WasmBreakpointSiteMap::Enum e(breakpointSites_); !e.empty();
+       e.popFront()) {
+    WasmBreakpointSite* site = e.front().value();
+    MOZ_ASSERT(site->instanceObject == instance);
+
+    Breakpoint* nextbp;
+    for (Breakpoint* bp = site->firstBreakpoint(); bp; bp = nextbp) {
+      nextbp = bp->nextInSite();
+      MOZ_ASSERT(bp->site == site);
+      if ((!dbg || bp->debugger == dbg) &&
+          (!handler || bp->getHandler() == handler)) {
+        bp->delete_(gcx);
+      }
+    }
+    if (site->isEmpty()) {
+      gcx->delete_(instance, site, MemoryUse::BreakpointSite);
+      e.removeFront();
+    }
+  }
+}
+
+void DebugState::enableDebuggingForFunction(Instance* instance,
+                                            uint32_t funcIndex) {
+  instance->setDebugFilter(funcIndex, true);
+}
+
+void DebugState::disableDebuggingForFunction(Instance* instance,
+                                             uint32_t funcIndex) {
+  instance->setDebugFilter(funcIndex, false);
+}
+
+void DebugState::enableDebugTrap(Instance* instance) {
+  instance->setDebugTrapHandler(code_->segment(Tier::Debug).base() +
+                                metadata(Tier::Debug).debugTrapOffset);
+}
+
+void DebugState::disableDebugTrap(Instance* instance) {
+  instance->setDebugTrapHandler(nullptr);
+}
+
+void DebugState::adjustEnterAndLeaveFrameTrapsState(JSContext* cx,
+                                                    Instance* instance,
+                                                    bool enabled) {
+  MOZ_ASSERT_IF(!enabled, enterAndLeaveFrameTrapsCounter_ > 0);
+
+  bool wasEnabled = enterAndLeaveFrameTrapsCounter_ > 0;
+  enterAndLeaveFrameTrapsCounter_ += enabled ? 1 : -1;
+  bool stillEnabled = enterAndLeaveFrameTrapsCounter_ > 0;
+  if (wasEnabled == stillEnabled) {
+    return;
+  }
+
+  MOZ_RELEASE_ASSERT(&instance->metadata() == &metadata());
+  uint32_t numFuncs = metadata().debugNumFuncs();
+  if (enabled) {
+    MOZ_ASSERT(enterAndLeaveFrameTrapsCounter_ > 0);
+    for (uint32_t funcIdx = 0; funcIdx < numFuncs; funcIdx++) {
+      enableDebuggingForFunction(instance, funcIdx);
+    }
+    enableDebugTrap(instance);
+  } else {
+    MOZ_ASSERT(enterAndLeaveFrameTrapsCounter_ == 0);
+    bool anyEnabled = false;
+    for (uint32_t funcIdx = 0; funcIdx < numFuncs; funcIdx++) {
+      // For each function, disable the bit if nothing else is going on.  This
+      // means determining if there's stepping or breakpoints.
+      bool mustLeaveEnabled = stepperCounters_.lookup(funcIdx).found();
+      for (auto iter = breakpointSites_.iter();
+           !iter.done() && !mustLeaveEnabled; iter.next()) {
+        WasmBreakpointSite* site = iter.get().value();
+        const CallSite* callSite =
+            SlowCallSiteSearchByOffset(metadata(Tier::Debug), site->offset);
+        if (callSite) {
+          size_t debugTrapOffset = callSite->returnAddressOffset();
+          const ModuleSegment& codeSegment = code_->segment(Tier::Debug);
+          const CodeRange* codeRange =
+              code_->lookupFuncRange(codeSegment.base() + debugTrapOffset);
+          MOZ_ASSERT(codeRange);
+          mustLeaveEnabled = codeRange->funcIndex() == funcIdx;
+        }
+      }
+      if (mustLeaveEnabled) {
+        anyEnabled = true;
+      } else {
+        disableDebuggingForFunction(instance, funcIdx);
+      }
+    }
+    if (!anyEnabled) {
+      disableDebugTrap(instance);
+    }
+  }
+}
+
+void DebugState::ensureEnterFrameTrapsState(JSContext* cx, Instance* instance,
+                                            bool enabled) {
+  if (enterFrameTrapsEnabled_ == enabled) {
+    return;
+  }
+
+  adjustEnterAndLeaveFrameTrapsState(cx, instance, enabled);
+
+  enterFrameTrapsEnabled_ = enabled;
+}
+
+bool DebugState::debugGetLocalTypes(uint32_t funcIndex, ValTypeVector* locals,
+                                    size_t* argsLength,
+                                    StackResults* stackResults) {
+  const TypeContext& types = *metadata().types;
+  const FuncType& funcType = metadata().debugFuncType(funcIndex);
+  const ValTypeVector& args = funcType.args();
+  const ValTypeVector& results = funcType.results();
+  ResultType resultType(ResultType::Vector(results));
+  *argsLength = args.length();
+  *stackResults = ABIResultIter::HasStackResults(resultType)
+                      ? StackResults::HasStackResults
+                      : StackResults::NoStackResults;
+  if (!locals->appendAll(args)) {
+    return false;
+  }
+
+  // Decode local var types from wasm binary function body.
+  const CodeRange& range =
+      codeRanges(Tier::Debug)[funcToCodeRangeIndex(funcIndex)];
+  // In wasm, the Code points to the function start via funcLineOrBytecode.
+  size_t offsetInModule = range.funcLineOrBytecode();
+  Decoder d(bytecode().begin() + offsetInModule, bytecode().end(),
+            offsetInModule,
+            /* error = */ nullptr);
+  return DecodeValidatedLocalEntries(types, d, locals);
+}
+
+bool DebugState::getGlobal(Instance& instance, uint32_t globalIndex,
+                           MutableHandleValue vp) {
+  const GlobalDesc& global = metadata().globals[globalIndex];
+
+  if (global.isConstant()) {
+    LitVal value = global.constantValue();
+    switch (value.type().kind()) {
+      case ValType::I32:
+        vp.set(Int32Value(value.i32()));
+        break;
+      case ValType::I64:
+        // Just display as a Number; it's ok if we lose some precision
+        vp.set(NumberValue((double)value.i64()));
+        break;
+      case ValType::F32:
+        vp.set(NumberValue(JS::CanonicalizeNaN(value.f32())));
+        break;
+      case ValType::F64:
+        vp.set(NumberValue(JS::CanonicalizeNaN(value.f64())));
+        break;
+      case ValType::Ref:
+        // It's possible to do better.  We could try some kind of hashing
+        // scheme, to make the pointer recognizable without revealing it.
+        vp.set(MagicValue(JS_OPTIMIZED_OUT));
+        break;
+      case ValType::V128:
+        // Debugger must be updated to handle this, and should be updated to
+        // handle i64 in any case.
+        vp.set(MagicValue(JS_OPTIMIZED_OUT));
+        break;
+      default:
+        MOZ_CRASH("Global constant type");
+    }
+    return true;
+  }
+
+  void* dataPtr = instance.data() + global.offset();
+  if (global.isIndirect()) {
+    dataPtr = *static_cast<void**>(dataPtr);
+  }
+  switch (global.type().kind()) {
+    case ValType::I32: {
+      vp.set(Int32Value(*static_cast<int32_t*>(dataPtr)));
+      break;
+    }
+    case ValType::I64: {
+      // Just display as a Number; it's ok if we lose some precision
+      vp.set(NumberValue((double)*static_cast<int64_t*>(dataPtr)));
+      break;
+    }
+    case ValType::F32: {
+      vp.set(NumberValue(JS::CanonicalizeNaN(*static_cast<float*>(dataPtr))));
+      break;
+    }
+    case ValType::F64: {
+      vp.set(NumberValue(JS::CanonicalizeNaN(*static_cast<double*>(dataPtr))));
+      break;
+    }
+    case ValType::Ref: {
+      // Just hide it.  See above.
+      vp.set(MagicValue(JS_OPTIMIZED_OUT));
+      break;
+    }
+    case ValType::V128: {
+      // Just hide it.  See above.
+      vp.set(MagicValue(JS_OPTIMIZED_OUT));
+      break;
+    }
+    default: {
+      MOZ_CRASH("Global variable type");
+      break;
+    }
+  }
+  return true;
+}
+
+bool DebugState::getSourceMappingURL(JSContext* cx,
+                                     MutableHandleString result) const {
+  result.set(nullptr);
+
+  for (const CustomSection& customSection : module_->customSections()) {
+    const Bytes& sectionName = customSection.name;
+    if (strlen(SourceMappingURLSectionName) != sectionName.length() ||
+        memcmp(SourceMappingURLSectionName, sectionName.begin(),
+               sectionName.length()) != 0) {
+      continue;
+    }
+
+    // Parse found "SourceMappingURL" custom section.
+    Decoder d(customSection.payload->begin(), customSection.payload->end(), 0,
+              /* error = */ nullptr);
+    uint32_t nchars;
+    if (!d.readVarU32(&nchars)) {
+      return true;  // ignoring invalid section data
+    }
+    const uint8_t* chars;
+    if (!d.readBytes(nchars, &chars) || d.currentPosition() != d.end()) {
+      return true;  // ignoring invalid section data
+    }
+
+    JS::UTF8Chars utf8Chars(reinterpret_cast<const char*>(chars), nchars);
+    JSString* str = JS_NewStringCopyUTF8N(cx, utf8Chars);
+    if (!str) {
+      return false;
+    }
+    result.set(str);
+    return true;
+  }
+
+  // Check presence of "SourceMap:" HTTP response header.
+  char* sourceMapURL = metadata().sourceMapURL.get();
+  if (sourceMapURL && strlen(sourceMapURL)) {
+    JS::UTF8Chars utf8Chars(sourceMapURL, strlen(sourceMapURL));
+    JSString* str = JS_NewStringCopyUTF8N(cx, utf8Chars);
+    if (!str) {
+      return false;
+    }
+    result.set(str);
+  }
+  return true;
+}
+
+void DebugState::addSizeOfMisc(MallocSizeOf mallocSizeOf,
+                               Metadata::SeenSet* seenMetadata,
+                               Code::SeenSet* seenCode, size_t* code,
+                               size_t* data) const {
+  code_->addSizeOfMiscIfNotSeen(mallocSizeOf, seenMetadata, seenCode, code,
+                                data);
+  module_->addSizeOfMisc(mallocSizeOf, seenMetadata, seenCode, code, data);
+}