[Bug java/12739] New: gcj emits dead bytecode

[Bug java/12739] New: gcj emits dead bytecode

[jsturm at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12739

           Summary: gcj emits dead bytecode
           Product: gcc
           Version: 3.4
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: java
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jsturm at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org

For the test case:

class T {
  int t() { try { return 0; } finally { } }
}

Compare the bytecode created with 3.2.2:

Method name:"t" Signature: 6=()int
Attribute "Code", length:26, max_stack:1, max_locals:1, code_length:2
  0: iconst_0
  1: ireturn

vs. current CVS:

Method name:"t" Signature: 6=()int
Attribute "Code", length:48, max_stack:2, max_locals:4, code_length:16
  0: iconst_0
  1: istore_1
  2: jsr 13
  5: iload_1
  6: ireturn
  7: astore_3
  8: jsr 13
 11: aload_3
 12: athrow
 13: astore_2
 14: ret 2
Exceptions (count: 1):
  start: 0, end: 7, handler: 7, type: 0 /* finally */

Probably caused by:

2003-09-03  Jeff Sturm  <jsturm@one-point.com>
        * parse.y: Include cgraph.h.
        (block): Don't special-case empty block production.

[Bug java/12739] gcj emits dead bytecode

[jsturm at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12739



------- Additional Comments From jsturm at gcc dot gnu dot org  2003-10-23 03:28 -------
Forgot to mention: this is a 3.4 regression, though we are no worse off than
javac (which doesn't strip the useless try/finally).

[Bug java/12739] [3.4 Regression] gcj emits dead bytecode

[pinskia at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12739


pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |pessimizes-code
            Summary|gcj emits dead bytecode     |[3.4 Regression] gcj emits
                   |                            |dead bytecode
   Target Milestone|---                         |3.4

[Bug java/12739] [3.4 Regression] gcj emits dead bytecode

[pinskia at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12739


pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2003-10-23 03:33:43
               date|                            |


------- Additional Comments From pinskia at gcc dot gnu dot org  2003-10-23 03:33 -------
Forgot to mention I can confirm this on the mainline (20031022).

[Bug java/12739] [3.4 Regression] gcj emits dead bytecode

[jsturm at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12739


jsturm at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2003-10-23 03:33:43         |2003-10-27 18:05:55
               date|                            |


------- Additional Comments From jsturm at gcc dot gnu dot org  2003-10-27 18:05 -------
http://gcc.gnu.org/ml/gcc-patches/2003-10/msg02405.html

[Bug java/12739] [3.4 Regression] gcj emits dead bytecode

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2003-11-18 03:42 -------
Subject: Bug 12739

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	jsturm@gcc.gnu.org	2003-11-18 03:42:30

Modified files:
	gcc/java       : ChangeLog java-tree.h parse.y 

Log message:
	Fix PR java/12739.
	* java-tree.h (BLOCK_EMPTY_P): Define.
	* parse.y (java_complete_lhs): Check for empty blocks
	in TRY_FINALLY_EXPR case.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/java/ChangeLog.diff?cvsroot=gcc&r1=1.1293&r2=1.1294
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/java/java-tree.h.diff?cvsroot=gcc&r1=1.187&r2=1.188
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/java/parse.y.diff?cvsroot=gcc&r1=1.455&r2=1.456



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12739

[Bug java/12739] [3.4 Regression] gcj emits dead bytecode

[jsturm at gcc dot gnu dot org]

------- Additional Comments From jsturm at gcc dot gnu dot org  2003-11-18 03:53 -------
Patch applied.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12739