From bbc68d41103498b7cd311cfc159998acc40a4c1a Mon Sep 17 00:00:00 2001
From: gsathya <gsathya@chromium.org>
Date: Wed, 14 Dec 2016 13:03:47 -0800
Subject: [PATCH] [parser] remove %catch parsing

Promise catch prediction no longer has to be threaded through the
parser since the code using %catch has been moved to TF codestubs.

This is currently dead code.

BUG=v8:5343,v8:5741

Review-Url: https://codereview.chromium.org/2575133002
Cr-Commit-Position: refs/heads/master@{#41701}
---
 src/ast/ast.h             |  9 ---------
 src/ast/prettyprinter.cc  |  7 ++++---
 src/parsing/parser-base.h |  3 ---
 src/parsing/parser.cc     | 12 +++---------
 4 files changed, 7 insertions(+), 24 deletions(-)

diff --git a/src/ast/ast.h b/src/ast/ast.h
index d60cee90a0..c518248c28 100644
--- a/src/ast/ast.h
+++ b/src/ast/ast.h
@@ -3237,15 +3237,6 @@ class AstNodeFactory final BASE_EMBEDDED {
         try_block, scope, variable, catch_block, HandlerTable::UNCAUGHT, pos);
   }
 
-  TryCatchStatement* NewTryCatchStatementForPromiseReject(Block* try_block,
-                                                          Scope* scope,
-                                                          Variable* variable,
-                                                          Block* catch_block,
-                                                          int pos) {
-    return new (zone_) TryCatchStatement(
-        try_block, scope, variable, catch_block, HandlerTable::PROMISE, pos);
-  }
-
   TryCatchStatement* NewTryCatchStatementForDesugaring(Block* try_block,
                                                        Scope* scope,
                                                        Variable* variable,
diff --git a/src/ast/prettyprinter.cc b/src/ast/prettyprinter.cc
index 2f939554ab..59690a856b 100644
--- a/src/ast/prettyprinter.cc
+++ b/src/ast/prettyprinter.cc
@@ -879,15 +879,16 @@ void AstPrinter::PrintTryStatement(TryStatement* node) {
     case HandlerTable::CAUGHT:
       prediction = "CAUGHT";
       break;
-    case HandlerTable::PROMISE:
-      prediction = "PROMISE";
-      break;
     case HandlerTable::DESUGARING:
       prediction = "DESUGARING";
       break;
     case HandlerTable::ASYNC_AWAIT:
       prediction = "ASYNC_AWAIT";
       break;
+    case HandlerTable::PROMISE:
+      // Catch prediction resulting in promise rejections aren't
+      // parsed by the parser.
+      UNREACHABLE();
   }
   Print(" %s\n", prediction);
 }
diff --git a/src/parsing/parser-base.h b/src/parsing/parser-base.h
index 3efb207c1f..ba89162129 100644
--- a/src/parsing/parser-base.h
+++ b/src/parsing/parser-base.h
@@ -642,7 +642,6 @@ class ParserBase {
           scope(nullptr),
           init_block(parser->impl()->NullBlock()),
           inner_block(parser->impl()->NullBlock()),
-          for_promise_reject(false),
           bound_names(1, parser->zone()),
           tail_call_expressions(parser->zone()) {}
     IdentifierT name;
@@ -651,7 +650,6 @@ class ParserBase {
     Scope* scope;
     BlockT init_block;
     BlockT inner_block;
-    bool for_promise_reject;
     ZoneList<const AstRawString*> bound_names;
     TailCallExpressionList tail_call_expressions;
   };
@@ -5121,7 +5119,6 @@ typename ParserBase<Impl>::StatementT ParserBase<Impl>::ParseTryStatement(
   }
 
   CatchInfo catch_info(this);
-  catch_info.for_promise_reject = allow_natives() && Check(Token::MOD);
 
   if (peek() != Token::CATCH && peek() != Token::FINALLY) {
     ReportMessage(MessageTemplate::kNoCatchOrFinally);
diff --git a/src/parsing/parser.cc b/src/parsing/parser.cc
index dffad26ecb..1386611862 100644
--- a/src/parsing/parser.cc
+++ b/src/parsing/parser.cc
@@ -1814,15 +1814,9 @@ Statement* Parser::RewriteTryStatement(Block* try_block, Block* catch_block,
     DCHECK_NOT_NULL(catch_info.scope);
     DCHECK_NOT_NULL(catch_info.variable);
     TryCatchStatement* statement;
-    if (catch_info.for_promise_reject) {
-      statement = factory()->NewTryCatchStatementForPromiseReject(
-          try_block, catch_info.scope, catch_info.variable, catch_block,
-          kNoSourcePosition);
-    } else {
-      statement = factory()->NewTryCatchStatement(
-          try_block, catch_info.scope, catch_info.variable, catch_block,
-          kNoSourcePosition);
-    }
+    statement = factory()->NewTryCatchStatement(try_block, catch_info.scope,
+                                                catch_info.variable,
+                                                catch_block, kNoSourcePosition);
 
     try_block = factory()->NewBlock(nullptr, 1, false, kNoSourcePosition);
     try_block->statements()->Add(statement, zone());