[PULL 1/6] accel/tcg: Avoid load of icount_decr if unused

Richard Henderson posted 6 patches 1 year, 6 months ago
Maintainers: Richard Henderson <richard.henderson@linaro.org>, Paolo Bonzini <pbonzini@redhat.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Aurelien Jarno <aurelien@aurel32.net>, Jiaxun Yang <jiaxun.yang@flygoat.com>, Aleksandar Rikalo <aleksandar.rikalo@syrmia.com>
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[PULL 1/6] accel/tcg: Avoid load of icount_decr if unused
Posted by Richard Henderson 1 year, 6 months ago
With CF_NOIRQ and without !CF_USE_ICOUNT, the load isn't used.
Avoid emitting it.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 accel/tcg/translator.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/accel/tcg/translator.c b/accel/tcg/translator.c
index 1a6a5448c8..a3983019a5 100644
--- a/accel/tcg/translator.c
+++ b/accel/tcg/translator.c
@@ -49,12 +49,15 @@ bool translator_io_start(DisasContextBase *db)
 
 static TCGOp *gen_tb_start(uint32_t cflags)
 {
-    TCGv_i32 count = tcg_temp_new_i32();
+    TCGv_i32 count = NULL;
     TCGOp *icount_start_insn = NULL;
 
-    tcg_gen_ld_i32(count, cpu_env,
-                   offsetof(ArchCPU, neg.icount_decr.u32) -
-                   offsetof(ArchCPU, env));
+    if ((cflags & CF_USE_ICOUNT) || !(cflags & CF_NOIRQ)) {
+        count = tcg_temp_new_i32();
+        tcg_gen_ld_i32(count, cpu_env,
+                       offsetof(ArchCPU, neg.icount_decr.u32) -
+                       offsetof(ArchCPU, env));
+    }
 
     if (cflags & CF_USE_ICOUNT) {
         /*
-- 
2.34.1