Allow constant multiply both ways.

src/typing-asm.cc

 // Copyright 2015 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/typing-asm.h"
 
 #include <limits>
 
 #include "src/v8.h"
 
@@ skipping 1191 matching lines @@
     case Token::MOD: {
       RECURSE(VisitWithExpectation(
           expr->left(), Type::Number(),
           "left arithmetic operand expected to be number"));
       Type* left_type = computed_type_;
       int left_intish = intish_;
       RECURSE(VisitWithExpectation(
           expr->right(), Type::Number(),
           "right arithmetic operand expected to be number"));
       Type* right_type = computed_type_;
       int right_intish = intish_;

[titzer, 2016/02/23 15:52:18]

probably want int32_t here?

[bradn, 2016/02/23 16:27:09]

I suppose. Done.

       Type* type = Type::Union(left_type, right_type, zone());
       if (type->Is(cache_.kAsmInt)) {
         if (expr->op() == Token::MUL) {
+          int32_t i;
+          Literal* left = expr->left()->AsLiteral();
           Literal* right = expr->right()->AsLiteral();
-          if (!right) {
-            FAIL(expr, "direct integer multiply forbidden");
-          }
-          if (!right->value()->IsNumber()) {
-            FAIL(expr, "multiply must be by an integer");
-          }
-          int32_t i;
-          if (!right->value()->ToInt32(&i)) {
-            FAIL(expr, "multiply must be a signed integer");
+          if (left != nullptr && left->value()->IsNumber() &&
+              left->value()->ToInt32(&i)) {
+            if (right_intish != 0) {
+              FAIL(expr, "intish not allowed in multiply");
+            }
+          } else if (right != nullptr && right->value()->IsNumber() &&
+                     right->value()->ToInt32(&i)) {
+            if (left_intish != 0) {
+              FAIL(expr, "intish not allowed in multiply");
+            }
+          } else {
+            FAIL(expr, "multiply must be by an literal integer");

[titzer, 2016/02/23 15:52:18]

by "an integer literal" ?

[bradn, 2016/02/23 16:27:09]

Done.

           }
           i = abs(i);
-          if (i >= 1 << 20) {
+          if (i >= (1 << 20)) {
             FAIL(expr, "multiply must be by value in -2^20 < n < 2^20");
           }
           intish_ = i;
           IntersectResult(expr, cache_.kAsmInt);
           return;
         } else {
           intish_ = left_intish + right_intish + 1;
           if (expr->op() == Token::ADD || expr->op() == Token::SUB) {
             if (intish_ > kMaxUncombinedAdditiveSteps) {
               FAIL(expr, "too many consecutive additive ops");
@@ skipping 316 matching lines @@
 }
 
 
 void AsmTyper::VisitRewritableExpression(RewritableExpression* expr) {
   RECURSE(Visit(expr->expression()));
 }
 
 
 }  // namespace internal
 }  // namespace v8