* compile.c (case_when_optimizable_literal): When float value can be

  treated as integer, add to table hash of case that way.
  based on a patch from Ikuo KOBORI. [ruby-dev:42038]

* insnf.def (opt_case_dispatch): ditto.

* test/ruby/test_case.rb: add tests.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@29203 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

4 files changed, 55 insertions, 8 deletions

diff --git a/ChangeLog b/ChangeLog
index 481f44d2e5..85f860766e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+Thu Sep  9 22:34:48 2010  wanabe  <s.wanabe@gmail.com>
+
+	* compile.c (case_when_optimizable_literal): When float value can be
+	  treated as integer, add to table hash of case that way.
+	  based on a patch from Ikuo KOBORI. [ruby-dev:42038]
+
+	* insnf.def (opt_case_dispatch): ditto.
+
+	* test/ruby/test_case.rb: add tests.
+
 Thu Sep  9 17:15:15 2010  NAKAMURA, Hiroshi  <nahi@ruby-lang.org>
 
 	* test/net/http/test_https.rb (test_identity_verify_failure): follows
diff --git a/compile.c b/compile.c
index 2fd804cac4..8cbf253cf2 100644
--- a/compile.c
+++ b/compile.c
@@ -2303,6 +2303,11 @@ case_when_optimizable_literal(NODE * node)
     switch (nd_type(node)) {
       case NODE_LIT: {
 	VALUE v = node->nd_lit;
+	double ival;
+	if (TYPE(v) == T_FLOAT &&
+	    modf(RFLOAT_VALUE(v), &ival) == 0.0) {
+	    return FIXABLE(ival) ? LONG2FIX((long)ival) : rb_dbl2big(ival);
+	}
 	if (SYMBOL_P(v) || rb_obj_is_kind_of(v, rb_cNumeric)) {
 	    return v;
 	}
diff --git a/insns.def b/insns.def
index fcd97ae613..6db675214a 100644
--- a/insns.def
+++ b/insns.def
@@ -1260,16 +1260,28 @@ opt_case_dispatch
 (..., VALUE key)
 () // inc += -1;
 {
-    if (BASIC_OP_UNREDEFINED_P(BOP_EQQ)) {
-	VALUE val;
-	if (st_lookup(RHASH_TBL(hash), key, &val)) {
-	    JUMP(FIX2INT(val));
+    switch(TYPE(key)) {
+      case T_FLOAT: {
+	double ival;
+	if (modf(RFLOAT_VALUE(key), &ival) == 0.0) {
+	    key = FIXABLE(ival) ? LONG2FIX((long)ival) : rb_dbl2big(ival);
 	}
-	else {
-	    JUMP(else_offset);
+      }
+      case T_SYMBOL: /* fall through */
+      case T_FIXNUM:
+      case T_BIGNUM:
+      case T_STRING:
+	if (BASIC_OP_UNREDEFINED_P(BOP_EQQ)) {
+	    VALUE val;
+	    if (st_lookup(RHASH_TBL(hash), key, &val)) {
+		JUMP(FIX2INT(val));
+	    }
+	    else {
+		JUMP(else_offset);
+	    }
+	    break;
 	}
-    }
-    else {
+      default: { /* fall through (else) */
 	struct opt_case_dispatch_i_arg arg;
 
 	arg.obj = key;
@@ -1282,6 +1294,7 @@ opt_case_dispatch
 	else {
 	    JUMP(else_offset);
 	}
+      }
     }
 }
 
diff --git a/test/ruby/test_case.rb b/test/ruby/test_case.rb
index 98498dada6..0067b74e2b 100644
--- a/test/ruby/test_case.rb
+++ b/test/ruby/test_case.rb
@@ -84,4 +84,23 @@ class TestCase < Test::Unit::TestCase
       class Fixnum; undef ===; def ===(o); p 42; true; end; end; case 1; when 1; end
     EOS
   end
+
+  def test_optimization
+    case 1
+    when 0.9, 1.1
+      assert(false)
+    when 1.0
+      assert(true)
+    else
+      assert(false)
+    end
+    case 536870912
+    when 536870911.9, 536870912.1
+      assert(false)
+    when 536870912.0
+      assert(true)
+    else
+      assert(false)
+    end
+  end
 end