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

src/compiler/ppc/code-generator-ppc.cc

 // Copyright 2014 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 "src/compiler/code-generator.h"
 
 #include "src/compilation-info.h"
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
@@ skipping 16 matching lines @@
   PPCOperandConverter(CodeGenerator* gen, Instruction* instr)
       : InstructionOperandConverter(gen, instr) {}
 
   size_t OutputCount() { return instr_->OutputCount(); }
 
   RCBit OutputRCBit() const {
     switch (instr_->flags_mode()) {
       case kFlags_branch:
       case kFlags_deoptimize:
       case kFlags_set:
+      case kFlags_trap:
         return SetRC;
       case kFlags_none:
         return LeaveRC;
     }
     UNREACHABLE();
     return LeaveRC;
   }
 
   bool CompareLogical() const {
     switch (instr_->flags_condition()) {
@@ skipping 1948 matching lines @@
   }
   __ b(cond, tlabel, cr);
   if (!branch->fallthru) __ b(flabel);  // no fallthru to flabel.
 }
 
 
 void CodeGenerator::AssembleArchJump(RpoNumber target) {
   if (!IsNextInAssemblyOrder(target)) __ b(GetLabel(target));
 }
 
+void CodeGenerator::AssembleArchTrap(Instruction* instr,
+                                     FlagsCondition condition) {
+  UNREACHABLE();
+}
 
 // Assembles boolean materializations after an instruction.
 void CodeGenerator::AssembleArchBoolean(Instruction* instr,
                                         FlagsCondition condition) {
   PPCOperandConverter i(this, instr);
   Label done;
   ArchOpcode op = instr->arch_opcode();
   CRegister cr = cr0;
   int reg_value = -1;
 
@@ skipping 460 matching lines @@
       padding_size -= v8::internal::Assembler::kInstrSize;
     }
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8