[Bug target/36224] New: vec_widen_smult_{hi,lo}_v4si generates pmuludq instruction

[Bug target/36224] New: vec_widen_smult_{hi,lo}_v4si generates pmuludq instruction

[gnu at the-meissners dot org]

The vec_widen_smult_{hi,lo}_v4si functions are incorrect, in that they generate
the pmuludq instruction, which does a 32x32->64 unsigned multiply.  For
example, multiplying -13 * 15 = gives 64424509245 with the current code, when
it should give -195.

The sse5 instructions pmacsdqh and pmacsdql could do this instruction, but not
anything in the standard sse2 set.


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           Summary: vec_widen_smult_{hi,lo}_v4si generates pmuludq
                    instruction
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: gnu at the-meissners dot org
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36224

[Bug target/36224] vec_widen_smult_{hi,lo}_v4si generates pmuludq instruction

[gnu at the-meissners dot org]

------- Comment #1 from gnu at the-meissners dot org  2008-05-12 20:00 -------
Created an attachment (id=15631)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=15631&action=view)
Test case for bug 36224


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36224

[Bug target/36224] vec_widen_smult_{hi,lo}_v4si generates pmuludq instruction

[ubizjak at gmail dot com]

------- Comment #2 from ubizjak at gmail dot com  2008-05-20 06:40 -------
Fixed by:

Author: meissner
Date: Wed May 14 18:02:56 2008
New Revision: 135302

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=135302
Log:
Fix pr36224

Added:
    trunk/gcc/testsuite/gcc.dg/pr36224.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/i386/sse.md
    trunk/gcc/testsuite/ChangeLog


and

Author: meissner
Date: Mon May 19 20:03:48 2008
New Revision: 135580

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=135580
Log:
Backport fix for 36224

Added:
    branches/gcc-4_3-branch/gcc/testsuite/gcc.dg/pr36224.c
Modified:
    branches/gcc-4_3-branch/gcc/ChangeLog
    branches/gcc-4_3-branch/gcc/config/i386/sse.md
    branches/gcc-4_3-branch/gcc/testsuite/ChangeLog

BTW: Please copy ChangeLog entry (without author line) into the commit text in
order to automatically update Bugzilla PR.


-- 

ubizjak at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2008-05-20 06:40:14
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36224

[Bug target/36224] vec_widen_smult_{hi,lo}_v4si generates pmuludq instruction

[ubizjak at gmail dot com]

------- Comment #3 from ubizjak at gmail dot com  2008-05-20 06:41 -------
Fixed.


-- 

ubizjak at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |http://gcc.gnu.org/ml/gcc-
                   |                            |patches/2008-
                   |                            |05/msg00842.html
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.3.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36224