[wasm] Introduce the TrapIf and TrapUnless operators to generate trap code.

src/runtime/runtime.h

 // Copyright 2012 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.
 
 #ifndef V8_RUNTIME_RUNTIME_H_
 #define V8_RUNTIME_RUNTIME_H_
 
 #include <memory>
 
 #include "src/allocation.h"
@@ skipping 908 matching lines @@
   F(ArrayBufferViewGetByteOffset, 1, 1)      \
   F(TypedArrayGetLength, 1, 1)               \
   F(TypedArrayGetBuffer, 1, 1)               \
   F(TypedArraySetFastCases, 3, 1)            \
   F(TypedArrayMaxSizeInHeap, 0, 1)           \
   F(IsTypedArray, 1, 1)                      \
   F(IsSharedTypedArray, 1, 1)                \
   F(IsSharedIntegerTypedArray, 1, 1)         \
   F(IsSharedInteger32TypedArray, 1, 1)
 
-#define FOR_EACH_INTRINSIC_WASM(F) \
-  F(WasmGrowMemory, 1, 1)          \
-  F(WasmMemorySize, 0, 1)          \
-  F(ThrowWasmError, 2, 1)          \
-  F(WasmThrowTypeError, 0, 1)      \
-  F(WasmThrow, 2, 1)               \
-  F(WasmGetCaughtExceptionValue, 1, 1)
+#define FOR_EACH_INTRINSIC_WASM(F)           \
+  F(WasmGrowMemory, 1, 1)                    \
+  F(WasmMemorySize, 0, 1)                    \
+  F(ThrowWasmError, 2, 1)                    \
+  F(WasmThrowTypeError, 0, 1)                \
+  F(WasmThrow, 2, 1)                         \
+  F(WasmGetCaughtExceptionValue, 1, 1)       \
+  F(ThrowWasmTrapUnreachable, 0, 1)          \

[titzer, 2016/12/12 14:21:34]

"ThrowWasmTrap" is kind of an odd phrase.
What about "ThrowWasmXXXError"?

[ahaas, 2016/12/13 12:38:59]

In the macro in wasm-opcodes.h the trap names have a "Trap" prefix, like
"TrapDivByZero". Renaming would mean that I either have to change the macro, or
that I cannot use the macro.

+  F(ThrowWasmTrapMemOutOfBounds, 0, 1)       \
+  F(ThrowWasmTrapDivByZero, 0, 1)            \
+  F(ThrowWasmTrapDivUnrepresentable, 0, 1)   \
+  F(ThrowWasmTrapRemByZero, 0, 1)            \
+  F(ThrowWasmTrapFloatUnrepresentable, 0, 1) \
+  F(ThrowWasmTrapFuncInvalid, 0, 1)          \
+  F(ThrowWasmTrapFuncSigMismatch, 0, 1)
 
 #define FOR_EACH_INTRINSIC_RETURN_PAIR(F) \
   F(LoadLookupSlotForCall, 1, 2)
 
 #define FOR_EACH_INTRINSIC_RETURN_TRIPLE(F) \
   F(ForInPrepare, 1, 3)
 
 // Most intrinsics are implemented in the runtime/ directory, but ICs are
 // implemented in ic.cc for now.
 #define FOR_EACH_INTRINSIC_IC(F)             \
@@ skipping 63 matching lines @@
   Object* Runtime_##name(int args_length, Object** args_object, \
                          Isolate* isolate);
 FOR_EACH_INTRINSIC_RETURN_OBJECT(F)
 #undef F
 
 //---------------------------------------------------------------------------
 // Runtime provides access to all C++ runtime functions.
 
 class Runtime : public AllStatic {
  public:
-  enum FunctionId {
+  enum FunctionId : int32_t {
 #define F(name, nargs, ressize) k##name,
 #define I(name, nargs, ressize) kInline##name,
-  FOR_EACH_INTRINSIC(F)
-  FOR_EACH_INTRINSIC(I)
+    FOR_EACH_INTRINSIC(F) FOR_EACH_INTRINSIC(I)
 #undef I
 #undef F
-    kNumFunctions,
+        kNumFunctions,
   };
 
   enum IntrinsicType { RUNTIME, INLINE };
 
   // Intrinsic function descriptor.
   struct Function {
     FunctionId function_id;
     IntrinsicType intrinsic_type;
     // The JS name of the function.
     const char* name;
@@ skipping 100 matching lines @@
 
 class DeclareGlobalsEvalFlag : public BitField<bool, 0, 1> {};
 class DeclareGlobalsNativeFlag : public BitField<bool, 1, 1> {};
 STATIC_ASSERT(LANGUAGE_END == 2);
 class DeclareGlobalsLanguageMode : public BitField<LanguageMode, 2, 1> {};
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_RUNTIME_RUNTIME_H_