[Qemu-devel] [PATCH v3 60/69] target/arm: Split gen_nop_hint

[Richard Henderson]

Now that all callers pass a constant value, split the switch
statement into the individual trans_* functions.

Reviewed-by: Peter Maydell <address@hidden>
Signed-off-by: Richard Henderson <address@hidden>
---
 target/arm/translate.c | 67 +++++++++++++++---------------------------
 1 file changed, 24 insertions(+), 43 deletions(-)

diff --git a/target/arm/translate.c b/target/arm/translate.c
index 1bbfea8ea4..c7d7834440 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -3042,46 +3042,6 @@ static void gen_exception_return(DisasContext *s, 
TCGv_i32 pc)
     gen_rfe(s, pc, load_cpu_field(spsr));
 }
 
-/*
- * For WFI we will halt the vCPU until an IRQ. For WFE and YIELD we
- * only call the helper when running single threaded TCG code to ensure
- * the next round-robin scheduled vCPU gets a crack. In MTTCG mode we
- * just skip this instruction. Currently the SEV/SEVL instructions
- * which are *one* of many ways to wake the CPU from WFE are not
- * implemented so we can't sleep like WFI does.
- */
-static void gen_nop_hint(DisasContext *s, int val)
-{
-    switch (val) {
-        /* When running in MTTCG we don't generate jumps to the yield and
-         * WFE helpers as it won't affect the scheduling of other vCPUs.
-         * If we wanted to more completely model WFE/SEV so we don't busy
-         * spin unnecessarily we would need to do something more involved.
-         */
-    case 1: /* yield */
-        if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
-            gen_set_pc_im(s, s->base.pc_next);
-            s->base.is_jmp = DISAS_YIELD;
-        }
-        break;
-    case 3: /* wfi */
-        gen_set_pc_im(s, s->base.pc_next);
-        s->base.is_jmp = DISAS_WFI;
-        break;
-    case 2: /* wfe */
-        if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
-            gen_set_pc_im(s, s->base.pc_next);
-            s->base.is_jmp = DISAS_WFE;
-        }
-        break;
-    case 4: /* sev */
-    case 5: /* sevl */
-        /* TODO: Implement SEV, SEVL and WFE.  May help SMP performance.  */
-    default: /* nop */
-        break;
-    }
-}
-
 #define CPU_V001 cpu_V0, cpu_V0, cpu_V1
 
 static inline void gen_neon_add(int size, TCGv_i32 t0, TCGv_i32 t1)
@@ -8168,19 +8128,40 @@ DO_SMLAWX(SMLAWT, 1, 1)
 
 static bool trans_YIELD(DisasContext *s, arg_YIELD *a)
 {
-    gen_nop_hint(s, 1);
+    /*
+     * When running single-threaded TCG code, use the helper to ensure that
+     * the next round-robin scheduled vCPU gets a crack.  When running in
+     * MTTCG we don't generate jumps to the helper as it won't affect the
+     * scheduling of other vCPUs.
+     */
+    if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
+        gen_set_pc_im(s, s->base.pc_next);
+        s->base.is_jmp = DISAS_YIELD;
+    }
     return true;
 }
 
 static bool trans_WFE(DisasContext *s, arg_WFE *a)
 {
-    gen_nop_hint(s, 2);
+    /*
+     * When running single-threaded TCG code, use the helper to ensure that
+     * the next round-robin scheduled vCPU gets a crack.  In MTTCG mode we
+     * just skip this instruction.  Currently the SEV/SEVL instructions,
+     * which are *one* of many ways to wake the CPU from WFE, are not
+     * implemented so we can't sleep like WFI does.
+     */
+    if (!(tb_cflags(s->base.tb) & CF_PARALLEL)) {
+        gen_set_pc_im(s, s->base.pc_next);
+        s->base.is_jmp = DISAS_WFE;
+    }
     return true;
 }
 
 static bool trans_WFI(DisasContext *s, arg_WFI *a)
 {
-    gen_nop_hint(s, 3);
+    /* For WFI, halt the vCPU until an IRQ. */
+    gen_set_pc_im(s, s->base.pc_next);
+    s->base.is_jmp = DISAS_WFI;
     return true;
 }
 
-- 
2.17.1