[PATCH, i386] Remove use of vpmacsdql instruction from multiplication.

["Gopalasubramanian, Ganesh" <Ganesh dot Gopalasubramanian at amd dot com>]

Hi,

The below patch fixes the issue with 64-bit multiplication.
The instruction "vpmacsdql" does signed 32-bit multiplication.
For V2DImode, we require widened unsigned multiplication.
So, replacing the "vpmacsdql" instruction with "vpmuludq" and "vpaddq".

This patch had been already discussed in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52908

With required change in the test xop-imul64-vector.c,  make check passes. Is it OK for upstream?

Regards
Ganesh

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d0a1253..c158612 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2014-06-10  Ganesh Gopalasubramanian <Ganesh.Gopalasubramanian@amd.com>
+
+       * config/i386/i386.c (ix86_expand_sse2_mulvxdi3): Issue instructions
+"vpmuludq" and "vpaddq" instead of "vpmacsdql" for handling 32-bit
+multiplication.
+
 2014-06-07  Jan Hubicka  <hubicka@ucw.cz>

        * cgraphunit.c (assemble_thunks_and_aliases): Expand thunks before
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 9105132..184d82d 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -45205,8 +45205,10 @@ ix86_expand_sse2_mulvxdi3 (rtx op0, rtx op1, rtx op2)
       /* t4: ((B*E)+(A*F))<<32, ((D*G)+(C*H))<<32 */
       emit_insn (gen_ashlv2di3 (t4, t3, GEN_INT (32)));

-      /* op0: (((B*E)+(A*F))<<32)+(B*F), (((D*G)+(C*H))<<32)+(D*H) */
-      emit_insn (gen_xop_pmacsdql (op0, op1, op2, t4));
+      /* Multiply lower parts and add all */
+      t5 = gen_reg_rtx (V2DImode);
+      emit_insn (gen_vec_widen_umult_even_v4si (t5, gen_lowpart (V4SImode, op1), gen_lowpart (V4SImode, op2)));
+      op0 = expand_binop (mode, add_optab, t5, t4, op0, 1, OPTAB_DIRECT);
     }
   else
     {
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index a6913af..757d3e3 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2014-06-10 Ganesh Gopalasubramanian  <Ganesh.Gopalasubramanian@amd.com>
+
+       * gcc.target/i386/xop-imul64-vector.c: Remove the check for
+       vpmacsdql instruction.
+
 2014-06-07  Eric Botcazou  <ebotcazou@adacore.com>

        * gnat.dg/opt38.adb: New test.
diff --git a/gcc/testsuite/gcc.target/i386/xop-imul64-vector.c b/gcc/testsuite/gcc.target/i386/xop-imul64-vector.c
index fbf605f..fc8c880 100644
--- a/gcc/testsuite/gcc.target/i386/xop-imul64-vector.c
+++ b/gcc/testsuite/gcc.target/i386/xop-imul64-vector.c
@@ -33,4 +33,3 @@ int main ()

 /* { dg-final { scan-assembler "vpmulld" } } */
 /* { dg-final { scan-assembler "vphadddq" } } */
-/* { dg-final { scan-assembler "vpmacsdql" } } */