WIP: wasm oob trap handling experiments

src/assembler.cc

Index: src/assembler.cc
diff --git a/src/assembler.cc b/src/assembler.cc
index f90a0a2ee5b7fe2292f0aeae5b0eb479f30d9796..2dbb2efcf97e9db3bc95e616222b48f96c801794 100644
--- a/src/assembler.cc
+++ b/src/assembler.cc
@@ -500,7 +500,7 @@ void RelocInfoWriter::Write(const RelocInfo* rinfo) {
     WriteShortTaggedData(rinfo->data(), kDeoptReasonTag);
   } else {
     WriteModeAndPC(pc_delta, rmode);
-    if (RelocInfo::IsComment(rmode)) {
+    if (RelocInfo::IsComment(rmode) || RelocInfo::IsWasmTrapLanding(rmode)) {
       WriteData(rinfo->data());
     } else if (RelocInfo::IsConstPool(rmode) ||
                RelocInfo::IsVeneerPool(rmode) || RelocInfo::IsDeoptId(rmode) ||
@@ -644,7 +644,8 @@ void RelocIterator::next() {
             return;
           }
           Advance(kIntSize);
-        } else if (RelocInfo::IsComment(rmode)) {
+        } else if (RelocInfo::IsComment(rmode) ||
+                   RelocInfo::IsWasmTrapLanding(rmode)) {
           if (SetMode(rmode)) {
             AdvanceReadData();
             return;
@@ -796,6 +797,8 @@ const char* RelocInfo::RelocModeName(RelocInfo::Mode rmode) {
       return "wasm memory size reference";
     case WASM_GLOBAL_REFERENCE:
       return "wasm global value reference";
+    case WASM_TRAP_LANDING:
+      return "wasm trap landing";
     case NUMBER_OF_MODES:
     case PC_JUMP:
       UNREACHABLE();
@@ -893,6 +896,7 @@ void RelocInfo::Verify(Isolate* isolate) {
     case WASM_MEMORY_REFERENCE:
     case WASM_MEMORY_SIZE_REFERENCE:
     case WASM_GLOBAL_REFERENCE:
+    case WASM_TRAP_LANDING:
     case NONE32:
     case NONE64:
       break;