[PULL 39/67] target/ppc: optimize p8 exception handling routines

[Nicholas Piggin <npiggin@gmail.com>]

From: Harsh Prateek Bora <harshpb@linux.ibm.com>

Most of the p8 exception handling accesses env->pending_interrupts and
env->spr[SPR_LPCR] at multiple places. Passing it directly as local
variables simplifies the code and avoids multiple indirect accesses.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 target/ppc/excp_helper.c | 60 +++++++++++++++++++++-------------------
 1 file changed, 32 insertions(+), 28 deletions(-)

diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index 7074e6c894..38733b7521 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -1765,39 +1765,42 @@ static int p7_next_unmasked_interrupt(CPUPPCState *env)
     PPC_INTERRUPT_CEXT | PPC_INTERRUPT_WDT | PPC_INTERRUPT_CDOORBELL |  \
     PPC_INTERRUPT_FIT | PPC_INTERRUPT_PIT | PPC_INTERRUPT_THERM)
 
-static int p8_interrupt_powersave(CPUPPCState *env)
+static int p8_interrupt_powersave(uint32_t pending_interrupts,
+                                  target_ulong lpcr)
 {
-    if ((env->pending_interrupts & PPC_INTERRUPT_EXT) &&
-        (env->spr[SPR_LPCR] & LPCR_P8_PECE2)) {
+    if ((pending_interrupts & PPC_INTERRUPT_EXT) &&
+        (lpcr & LPCR_P8_PECE2)) {
         return PPC_INTERRUPT_EXT;
     }
-    if ((env->pending_interrupts & PPC_INTERRUPT_DECR) &&
-        (env->spr[SPR_LPCR] & LPCR_P8_PECE3)) {
+    if ((pending_interrupts & PPC_INTERRUPT_DECR) &&
+        (lpcr & LPCR_P8_PECE3)) {
         return PPC_INTERRUPT_DECR;
     }
-    if ((env->pending_interrupts & PPC_INTERRUPT_MCK) &&
-        (env->spr[SPR_LPCR] & LPCR_P8_PECE4)) {
+    if ((pending_interrupts & PPC_INTERRUPT_MCK) &&
+        (lpcr & LPCR_P8_PECE4)) {
         return PPC_INTERRUPT_MCK;
     }
-    if ((env->pending_interrupts & PPC_INTERRUPT_HMI) &&
-        (env->spr[SPR_LPCR] & LPCR_P8_PECE4)) {
+    if ((pending_interrupts & PPC_INTERRUPT_HMI) &&
+        (lpcr & LPCR_P8_PECE4)) {
         return PPC_INTERRUPT_HMI;
     }
-    if ((env->pending_interrupts & PPC_INTERRUPT_DOORBELL) &&
-        (env->spr[SPR_LPCR] & LPCR_P8_PECE0)) {
+    if ((pending_interrupts & PPC_INTERRUPT_DOORBELL) &&
+        (lpcr & LPCR_P8_PECE0)) {
         return PPC_INTERRUPT_DOORBELL;
     }
-    if ((env->pending_interrupts & PPC_INTERRUPT_HDOORBELL) &&
-        (env->spr[SPR_LPCR] & LPCR_P8_PECE1)) {
+    if ((pending_interrupts & PPC_INTERRUPT_HDOORBELL) &&
+        (lpcr & LPCR_P8_PECE1)) {
         return PPC_INTERRUPT_HDOORBELL;
     }
-    if (env->pending_interrupts & PPC_INTERRUPT_RESET) {
+    if (pending_interrupts & PPC_INTERRUPT_RESET) {
         return PPC_INTERRUPT_RESET;
     }
     return 0;
 }
 
-static int p8_next_unmasked_interrupt(CPUPPCState *env)
+static int p8_next_unmasked_interrupt(CPUPPCState *env,
+                                      uint32_t pending_interrupts,
+                                      target_ulong lpcr)
 {
     CPUState *cs = env_cpu(env);
 
@@ -1808,18 +1811,18 @@ static int p8_next_unmasked_interrupt(CPUPPCState *env)
 
     if (cs->halted) {
         /* LPCR[PECE] controls which interrupts can exit power-saving mode */
-        return p8_interrupt_powersave(env);
+        return p8_interrupt_powersave(pending_interrupts, lpcr);
     }
 
     /* Machine check exception */
-    if (env->pending_interrupts & PPC_INTERRUPT_MCK) {
+    if (pending_interrupts & PPC_INTERRUPT_MCK) {
         return PPC_INTERRUPT_MCK;
     }
 
     /* Hypervisor decrementer exception */
-    if (env->pending_interrupts & PPC_INTERRUPT_HDECR) {
+    if (pending_interrupts & PPC_INTERRUPT_HDECR) {
         /* LPCR will be clear when not supported so this will work */
-        bool hdice = !!(env->spr[SPR_LPCR] & LPCR_HDICE);
+        bool hdice = !!(lpcr & LPCR_HDICE);
         if ((msr_ee || !FIELD_EX64_HV(env->msr)) && hdice) {
             /* HDEC clears on delivery */
             return PPC_INTERRUPT_HDECR;
@@ -1827,9 +1830,9 @@ static int p8_next_unmasked_interrupt(CPUPPCState *env)
     }
 
     /* External interrupt can ignore MSR:EE under some circumstances */
-    if (env->pending_interrupts & PPC_INTERRUPT_EXT) {
-        bool lpes0 = !!(env->spr[SPR_LPCR] & LPCR_LPES0);
-        bool heic = !!(env->spr[SPR_LPCR] & LPCR_HEIC);
+    if (pending_interrupts & PPC_INTERRUPT_EXT) {
+        bool lpes0 = !!(lpcr & LPCR_LPES0);
+        bool heic = !!(lpcr & LPCR_HEIC);
         /* HEIC blocks delivery to the hypervisor */
         if ((msr_ee && !(heic && FIELD_EX64_HV(env->msr) &&
             !FIELD_EX64(env->msr, MSR, PR))) ||
@@ -1839,20 +1842,20 @@ static int p8_next_unmasked_interrupt(CPUPPCState *env)
     }
     if (msr_ee != 0) {
         /* Decrementer exception */
-        if (env->pending_interrupts & PPC_INTERRUPT_DECR) {
+        if (pending_interrupts & PPC_INTERRUPT_DECR) {
             return PPC_INTERRUPT_DECR;
         }
-        if (env->pending_interrupts & PPC_INTERRUPT_DOORBELL) {
+        if (pending_interrupts & PPC_INTERRUPT_DOORBELL) {
             return PPC_INTERRUPT_DOORBELL;
         }
-        if (env->pending_interrupts & PPC_INTERRUPT_HDOORBELL) {
+        if (pending_interrupts & PPC_INTERRUPT_HDOORBELL) {
             return PPC_INTERRUPT_HDOORBELL;
         }
-        if (env->pending_interrupts & PPC_INTERRUPT_PERFM) {
+        if (pending_interrupts & PPC_INTERRUPT_PERFM) {
             return PPC_INTERRUPT_PERFM;
         }
         /* EBB exception */
-        if (env->pending_interrupts & PPC_INTERRUPT_EBB) {
+        if (pending_interrupts & PPC_INTERRUPT_EBB) {
             /*
              * EBB exception must be taken in problem state and
              * with BESCR_GE set.
@@ -2021,7 +2024,8 @@ static int ppc_next_unmasked_interrupt(CPUPPCState *env)
     case POWERPC_EXCP_POWER7:
         return p7_next_unmasked_interrupt(env);
     case POWERPC_EXCP_POWER8:
-        return p8_next_unmasked_interrupt(env);
+        return p8_next_unmasked_interrupt(env, env->pending_interrupts,
+                                          env->spr[SPR_LPCR]);
     case POWERPC_EXCP_POWER9:
     case POWERPC_EXCP_POWER10:
     case POWERPC_EXCP_POWER11:
-- 
2.45.2