[wasm] Move {WasmModuleObject::GetContainingFunction}.

This introduces {GetContainingWasmFunction} to replace the above method,
since calculating offsets into the wire bytes is independent of the
concrete module object and hence only needs the shared decoded module.

R=clemensh@chromium.org
BUG=v8:6847

Change-Id: I145d527506289686653979dbb135480cc42ea4c8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1809369
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63870}

src/objects/objects.cc

@@ -4656,8 +4656,26 @@ bool Script::GetPositionInfo(int position, PositionInfo* info,
   // directly.
   if (type() == Script::TYPE_WASM) {
     DCHECK_LE(0, position);
-    return WasmModuleObject::cast(wasm_module_object())
-        .GetPositionInfo(static_cast<uint32_t>(position), info);
+    wasm::NativeModule* native_module = wasm_native_module();
+    const wasm::WasmModule* module = native_module->module();
+    if (source_mapping_url().IsString()) {
+      if (module->functions.size() == 0) return false;
+      info->line = 0;
+      info->column = position;
+      info->line_start = module->functions[0].code.offset();
+      info->line_end = module->functions.back().code.end_offset();
+      return true;
+    }
+    int func_index = GetContainingWasmFunction(module, position);
+    if (func_index < 0) return false;
+
+    const wasm::WasmFunction& function = module->functions[func_index];
+
+    info->line = func_index;
+    info->column = position - function.code.offset();
+    info->line_start = function.code.offset();
+    info->line_end = function.code.end_offset();
+    return true;
   }
 
   if (line_ends().IsUndefined()) {

src/wasm/wasm-module.cc

@@ -67,6 +67,32 @@ int GetWasmFunctionOffset(const WasmModule* module, uint32_t func_index) {
   return static_cast<int>(functions[func_index].code.offset());
 }
 
+// static
+int GetContainingWasmFunction(const WasmModule* module, uint32_t byte_offset) {
+  const std::vector<WasmFunction>& functions = module->functions;
+
+  // Binary search for a function containing the given position.
+  int left = 0;                                    // inclusive
+  int right = static_cast<int>(functions.size());  // exclusive
+  if (right == 0) return false;
+  while (right - left > 1) {
+    int mid = left + (right - left) / 2;
+    if (functions[mid].code.offset() <= byte_offset) {
+      left = mid;
+    } else {
+      right = mid;
+    }
+  }
+  // If the found function does not contains the given position, return -1.
+  const WasmFunction& func = functions[left];
+  if (byte_offset < func.code.offset() ||
+      byte_offset >= func.code.end_offset()) {
+    return -1;
+  }
+
+  return left;
+}
+
 // static
 v8::debug::WasmDisassembly DisassembleWasmFunction(
     const WasmModule* module, const ModuleWireBytes& wire_bytes,

src/wasm/wasm-module.h

@@ -250,6 +250,11 @@ int GetExportWrapperIndex(const WasmModule* module, const FunctionSig* sig,
 // Returns -1 if the function index is invalid.
 int GetWasmFunctionOffset(const WasmModule* module, uint32_t func_index);
 
+// Returns the function containing the given byte offset.
+// Returns -1 if the byte offset is not contained in any function of this
+// module.
+int GetContainingWasmFunction(const WasmModule* module, uint32_t byte_offset);
+
 // Compute the disassembly of a wasm function.
 // Returns the disassembly string and a list of <byte_offset, line, column>
 // entries, mapping wasm byte offsets to line and column in the disassembly.

src/wasm/wasm-objects.cc

@@ -258,9 +258,10 @@ bool WasmModuleObject::SetBreakPoint(Handle<WasmModuleObject> module_object,
   Isolate* isolate = module_object->GetIsolate();
 
   // Find the function for this breakpoint.
-  int func_index = module_object->GetContainingFunction(*position);
+  const WasmModule* module = module_object->module();
+  int func_index = GetContainingWasmFunction(module, *position);
   if (func_index < 0) return false;
-  const WasmFunction& func = module_object->module()->functions[func_index];
+  const WasmFunction& func = module->functions[func_index];
   int offset_in_func = *position - func.code.offset();
 
   // According to the current design, we should only be called with valid
@@ -403,9 +404,10 @@ void WasmModuleObject::SetBreakpointsOnNewInstance(
     int position = breakpoint_info->source_position();
 
     // Find the function for this breakpoint, and set the breakpoint.
-    int func_index = module_object->GetContainingFunction(position);
+    const WasmModule* module = module_object->module();
+    int func_index = GetContainingWasmFunction(module, position);
     DCHECK_LE(0, func_index);
-    const WasmFunction& func = module_object->module()->functions[func_index];
+    const WasmFunction& func = module->functions[func_index];
     int offset_in_func = position - func.code.offset();
     WasmDebugInfo::SetBreakpoint(debug_info, func_index, offset_in_func);
   }
@@ -689,53 +691,6 @@ Vector<const uint8_t> WasmModuleObject::GetRawFunctionName(
   return Vector<const uint8_t>::cast(name);
 }
 
-int WasmModuleObject::GetContainingFunction(uint32_t byte_offset) {
-  const std::vector<WasmFunction>& functions = module()->functions;
-
-  // Binary search for a function containing the given position.
-  int left = 0;                                    // inclusive
-  int right = static_cast<int>(functions.size());  // exclusive
-  if (right == 0) return false;
-  while (right - left > 1) {
-    int mid = left + (right - left) / 2;
-    if (functions[mid].code.offset() <= byte_offset) {
-      left = mid;
-    } else {
-      right = mid;
-    }
-  }
-  // If the found function does not contains the given position, return -1.
-  const WasmFunction& func = functions[left];
-  if (byte_offset < func.code.offset() ||
-      byte_offset >= func.code.end_offset()) {
-    return -1;
-  }
-
-  return left;
-}
-
-bool WasmModuleObject::GetPositionInfo(uint32_t position,
-                                       Script::PositionInfo* info) {
-  if (script().source_mapping_url().IsString()) {
-    if (module()->functions.size() == 0) return false;
-    info->line = 0;
-    info->column = position;
-    info->line_start = module()->functions[0].code.offset();
-    info->line_end = module()->functions.back().code.end_offset();
-    return true;
-  }
-  int func_index = GetContainingFunction(position);
-  if (func_index < 0) return false;
-
-  const WasmFunction& function = module()->functions[func_index];
-
-  info->line = func_index;
-  info->column = position - function.code.offset();
-  info->line_start = function.code.offset();
-  info->line_end = function.code.end_offset();
-  return true;
-}
-
 Handle<WasmTableObject> WasmTableObject::New(Isolate* isolate,
                                              wasm::ValueType type,
                                              uint32_t initial, bool has_maximum,

src/wasm/wasm-objects.h

@@ -12,7 +12,6 @@
 #include "src/debug/debug.h"
 #include "src/heap/heap.h"
 #include "src/objects/objects.h"
-#include "src/objects/script.h"
 #include "src/wasm/value-type.h"
 
 // Has to be the last include (doesn't have include guards)
@@ -198,16 +197,6 @@ class WasmModuleObject : public JSObject {
   // Does not allocate, hence gc-safe.
   Vector<const uint8_t> GetRawFunctionName(uint32_t func_index);
 
-  // Returns the function containing the given byte offset.
-  // Returns -1 if the byte offset is not contained in any function of this
-  // module.
-  int GetContainingFunction(uint32_t byte_offset);
-
-  // Translate from byte offset in the module to function number and byte offset
-  // within that function, encoded as line and column in the position info.
-  // Returns true if the position is valid inside this module, false otherwise.
-  bool GetPositionInfo(uint32_t position, Script::PositionInfo* info);
-
   // Get the source position from a given function index and byte offset,
   // for either asm.js or pure Wasm modules.
   static int GetSourcePosition(Handle<WasmModuleObject>, uint32_t func_index,