[gcc r11-3419] [RS6000] Count rldimi constant insns

[gcc r11-3419] [RS6000] Count rldimi constant insns

[Alan Modra]

https://gcc.gnu.org/g:0075cea0fdccc2efb781f4f3c924007de37a3417

commit r11-3419-g0075cea0fdccc2efb781f4f3c924007de37a3417
Author: Alan Modra <amodra@gmail.com>
Date:   Wed Apr 1 13:34:47 2020 +1030

    [RS6000] Count rldimi constant insns
    
    rldimi is generated by rs6000_emit_set_long_const when the high and
    low 32 bits of a 64-bit constant are equal.
    
            PR target/93012
            * config/rs6000/rs6000.c (num_insns_constant_gpr): Count rldimi
            constants correctly.

Diff:
---
 gcc/config/rs6000/rs6000.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 6f204ca202a..5f4e2927a21 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -5731,7 +5731,7 @@ direct_return (void)
 
 /* Helper for num_insns_constant.  Calculate number of instructions to
    load VALUE to a single gpr using combinations of addi, addis, ori,
-   oris and sldi instructions.  */
+   oris, sldi and rldimi instructions.  */
 
 static int
 num_insns_constant_gpr (HOST_WIDE_INT value)
@@ -5759,7 +5759,7 @@ num_insns_constant_gpr (HOST_WIDE_INT value)
 
       high >>= 1;
 
-      if (low == 0)
+      if (low == 0 || low == high)
 	return num_insns_constant_gpr (high) + 1;
       else if (high == 0)
 	return num_insns_constant_gpr (low) + 1;