[Qemu-devel] [PATCH 20/22] target/openrisc: Optimize l.jal to next

[Richard Henderson]

This allows the tcg optimizer to see, and fold, all of the
constants involved in a GOT base register load sequence.

Signed-off-by: Richard Henderson <address@hidden>
---
 target/openrisc/translate.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/target/openrisc/translate.c b/target/openrisc/translate.c
index 66064e1..cda84b6 100644
--- a/target/openrisc/translate.c
+++ b/target/openrisc/translate.c
@@ -198,7 +198,11 @@ static void gen_jump(DisasContext *dc, int32_t n26, 
uint32_t reg, uint32_t op0)
         tcg_gen_movi_tl(jmp_pc, tmp_pc);
         break;
     case 0x01:     /* l.jal */
-        tcg_gen_movi_tl(cpu_R[9], (dc->pc + 8));
+        tcg_gen_movi_tl(cpu_R[9], dc->pc + 8);
+        /* Optimize jal being used to load the PC for PIC.  */
+        if (tmp_pc == dc->pc + 8) {
+            return;
+        }
         tcg_gen_movi_tl(jmp_pc, tmp_pc);
         break;
     case 0x03:     /* l.bnf */
-- 
2.9.3