commit f59d61807e8a3f9a319a679124d24160e11fe623
author scottb@google.com <scottb@google.com@8db76d5a-ed1c-0410-87a9-c151d255dfc7> Mon Mar 31 16:48:40 2008 +0000
committer scottb@google.com <scottb@google.com@8db76d5a-ed1c-0410-87a9-c151d255dfc7> Mon Mar 31 16:48:40 2008 +0000
tree 0daf28a69d14df4061f40cfec00ecb3601829be4
parent 4bf03e947fa91e7fb17b967f058fc3ce0dd3ea32

Partial roll-back of r2210; converting a div to a shift breaks for negative numerators.  That's what I get for not writing a unit test.

Found by: jeffreyconroy@yahoo.com



git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@2295 8db76d5a-ed1c-0410-87a9-c151d255dfc7

dev/core/src/com/google/gwt/dev/jjs/impl/DeadCodeElimination.java

diff --git a/dev/core/src/com/google/gwt/dev/jjs/impl/DeadCodeElimination.java b/dev/core/src/com/google/gwt/dev/jjs/impl/DeadCodeElimination.java
index 2d24c1f..7eedecc 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/impl/DeadCodeElimination.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/impl/DeadCodeElimination.java
@@ -140,13 +140,6 @@
             evalConcat(lhs, rhs, ctx);
           }
           break;
-        case DIV:
-        case ASG_DIV:
-          if (x.getType() != program.getTypePrimitiveFloat()
-              && x.getType() != program.getTypePrimitiveDouble()) {
-            divToShift(x, lhs, rhs, ctx);
-          }
-          break;
         default:
           if (op.isAssignment()) {
             lvalues.remove(lhs);
@@ -700,40 +693,6 @@
       return true;
     }
 
-    private void divToShift(JBinaryOperation x, JExpression lhs,
-        JExpression rhs, Context ctx) {
-      long divisor;
-      if (rhs instanceof JIntLiteral) {
-        divisor = ((JIntLiteral) rhs).getValue();
-      } else if (rhs instanceof JLongLiteral) {
-        divisor = ((JLongLiteral) rhs).getValue();
-      } else {
-        return;
-      }
-
-      if (divisor == 1) {
-        ctx.replaceMe(lhs);
-        return;
-      } else if (divisor == -1 && !x.getOp().isAssignment()) {
-        JPrefixOperation negOp = new JPrefixOperation(program,
-            x.getSourceInfo(), JUnaryOperator.NEG, lhs);
-        ctx.replaceMe(negOp);
-        return;
-      }
-
-      if (divisor > 1 && divisor == Long.highestOneBit(divisor)) {
-        // It's a power of two, convert to a shift operation.
-        int shift = Long.numberOfTrailingZeros(divisor);
-        JBinaryOperator op = x.getOp().isAssignment() ? JBinaryOperator.ASG_SHR
-            : JBinaryOperator.SHR;
-        JBinaryOperation binOp = new JBinaryOperation(program,
-            x.getSourceInfo(), lhs.getType(), op, lhs,
-            program.getLiteralInt(shift));
-        ctx.replaceMe(binOp);
-        return;
-      }
-    }
-
     private void evalConcat(JExpression lhs, JExpression rhs, Context ctx) {
       if (lhs instanceof JValueLiteral && rhs instanceof JValueLiteral) {
         Object lhsObj = ((JValueLiteral) lhs).getValueObj();