[PATCH] lround for PowerPC

[David Edelsohn <dje.gcc@gmail.com>]

PowerPC was missing a definition of the lroundMN pattern, which can be
implemented with  VSX instructions available in Power7.  Below is a
first draft.

- David

* config/rs6000/rs6000.md (*xsrdpidf2): New define_insn.
(lrounddfdi2): New define_expand.

diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index 8c53c40..eadbe1d 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -77,6 +77,7 @@
    UNSPEC_FRIN
    UNSPEC_FRIP
    UNSPEC_FRIZ
+   UNSPEC_XSRDPI
    UNSPEC_LD_MPIC              ; load_macho_picbase
    UNSPEC_RELD_MPIC            ; re-load_macho_picbase
    UNSPEC_MPIC_CORRECT         ; macho_correct_pic
@@ -5245,6 +5246,27 @@
   [(set_attr "type" "fp")
    (set_attr "fp_type" "fp_addsub_<Fs>")])

+(define_insn "*xsrdpidf2"
+  [(set (match_operand:DF 0 "gpc_reg_operand" "=<Fv>")
+       (unspec:DF [(match_operand:DF 1 "gpc_reg_operand" "<Fv>")]
+                  UNSPEC_XSRDPI))]
+  "TARGET_DF_FPR && TARGET_POPCNTD"
+  "xsrdpi %0,%1"
+  [(set_attr "type" "fp")])
+
+(define_expand "lrounddfdi2"
+  [(set (match_dup 2)
+       (unspec:DF [(match_operand:DF 1 "gpc_reg_operand" "<Fv>")]
+                  UNSPEC_XSRDPI))
+   (set (match_operand:DI 0 "gpc_reg_operand" "=d")
+       (unspec:DI [(match_dup 2)]
+                  UNSPEC_FCTID))]
+  "TARGET_DF_FPR && TARGET_POPCNTD
+   && flag_unsafe_math_optimizations && !flag_trapping_math"
+{
+  operands[2] = gen_reg_rtx (DFmode);
+})
+
 ; An UNSPEC is used so we don't have to support SImode in FP registers.
 (define_insn "stfiwx"
   [(set (match_operand:SI 0 "memory_operand" "=Z")