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

src/compiler/mips/instruction-selector-mips.cc

Index: src/compiler/mips/instruction-selector-mips.cc
diff --git a/src/compiler/mips/instruction-selector-mips.cc b/src/compiler/mips/instruction-selector-mips.cc
index ecf087fdab282fa7b7143aaf02fb611a2888bd10..1bb8f57e93d57bfc867845fb58b8f4f70ed206f0 100644
--- a/src/compiler/mips/instruction-selector-mips.cc
+++ b/src/compiler/mips/instruction-selector-mips.cc
@@ -1647,6 +1647,10 @@ void InstructionSelector::VisitDeoptimizeUnless(Node* node) {
   VisitWordCompareZero(this, node, node->InputAt(0), &cont);
 }
 
+void InstructionSelector::VisitTrapIf(Node* node) { UNREACHABLE(); }
+
+void InstructionSelector::VisitTrapUnless(Node* node) { UNREACHABLE(); }
+
 void InstructionSelector::VisitSwitch(Node* node, const SwitchInfo& sw) {
   MipsOperandGenerator g(this);
   InstructionOperand value_operand = g.UseRegister(node->InputAt(0));