[PULL 38/67] target/ppc: optimize p9 exception handling routines

[Nicholas Piggin <npiggin@gmail.com>]

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

Currently, p9 exception handling has multiple if-condition checks where
it does an indirect access to pending_interrupts and LPCR via env.
Pass the values during entry to avoid 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 | 72 ++++++++++++++++++++++------------------
 1 file changed, 39 insertions(+), 33 deletions(-)

diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index 087235bd62..7074e6c894 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -1872,60 +1872,65 @@ static int p8_next_unmasked_interrupt(CPUPPCState *env)
      PPC_INTERRUPT_WDT | PPC_INTERRUPT_CDOORBELL | PPC_INTERRUPT_FIT |  \
      PPC_INTERRUPT_PIT | PPC_INTERRUPT_THERM)
 
-static int p9_interrupt_powersave(CPUPPCState *env)
+static int p9_interrupt_powersave(CPUPPCState *env,
+                                  uint32_t pending_interrupts,
+                                  target_ulong lpcr)
 {
+
     /* External Exception */
-    if ((env->pending_interrupts & PPC_INTERRUPT_EXT) &&
-        (env->spr[SPR_LPCR] & LPCR_EEE)) {
-        bool heic = !!(env->spr[SPR_LPCR] & LPCR_HEIC);
+    if ((pending_interrupts & PPC_INTERRUPT_EXT) &&
+        (lpcr & LPCR_EEE)) {
+        bool heic = !!(lpcr & LPCR_HEIC);
         if (!heic || !FIELD_EX64_HV(env->msr) ||
             FIELD_EX64(env->msr, MSR, PR)) {
             return PPC_INTERRUPT_EXT;
         }
     }
     /* Decrementer Exception */
-    if ((env->pending_interrupts & PPC_INTERRUPT_DECR) &&
-        (env->spr[SPR_LPCR] & LPCR_DEE)) {
+    if ((pending_interrupts & PPC_INTERRUPT_DECR) &&
+        (lpcr & LPCR_DEE)) {
         return PPC_INTERRUPT_DECR;
     }
     /* Machine Check or Hypervisor Maintenance Exception */
-    if (env->spr[SPR_LPCR] & LPCR_OEE) {
-        if (env->pending_interrupts & PPC_INTERRUPT_MCK) {
+    if (lpcr & LPCR_OEE) {
+        if (pending_interrupts & PPC_INTERRUPT_MCK) {
             return PPC_INTERRUPT_MCK;
         }
-        if (env->pending_interrupts & PPC_INTERRUPT_HMI) {
+        if (pending_interrupts & PPC_INTERRUPT_HMI) {
             return PPC_INTERRUPT_HMI;
         }
     }
     /* Privileged Doorbell Exception */
-    if ((env->pending_interrupts & PPC_INTERRUPT_DOORBELL) &&
-        (env->spr[SPR_LPCR] & LPCR_PDEE)) {
+    if ((pending_interrupts & PPC_INTERRUPT_DOORBELL) &&
+        (lpcr & LPCR_PDEE)) {
         return PPC_INTERRUPT_DOORBELL;
     }
     /* Hypervisor Doorbell Exception */
-    if ((env->pending_interrupts & PPC_INTERRUPT_HDOORBELL) &&
-        (env->spr[SPR_LPCR] & LPCR_HDEE)) {
+    if ((pending_interrupts & PPC_INTERRUPT_HDOORBELL) &&
+        (lpcr & LPCR_HDEE)) {
         return PPC_INTERRUPT_HDOORBELL;
     }
     /* Hypervisor virtualization exception */
-    if ((env->pending_interrupts & PPC_INTERRUPT_HVIRT) &&
-        (env->spr[SPR_LPCR] & LPCR_HVEE)) {
+    if ((pending_interrupts & PPC_INTERRUPT_HVIRT) &&
+        (lpcr & LPCR_HVEE)) {
         return PPC_INTERRUPT_HVIRT;
     }
-    if (env->pending_interrupts & PPC_INTERRUPT_RESET) {
+    if (pending_interrupts & PPC_INTERRUPT_RESET) {
         return PPC_INTERRUPT_RESET;
     }
     return 0;
 }
 
-static int p9_next_unmasked_interrupt(CPUPPCState *env)
+static int p9_next_unmasked_interrupt(CPUPPCState *env,
+                                      uint32_t pending_interrupts,
+                                      target_ulong lpcr)
 {
     CPUState *cs = env_cpu(env);
 
     /* Ignore MSR[EE] when coming out of some power management states */
     bool msr_ee = FIELD_EX64(env->msr, MSR, EE) || env->resume_as_sreset;
 
-    assert((env->pending_interrupts & P9_UNUSED_INTERRUPTS) == 0);
+    assert((pending_interrupts & P9_UNUSED_INTERRUPTS) == 0);
 
     if (cs->halted) {
         if (env->spr[SPR_PSSCR] & PSSCR_EC) {
@@ -1933,7 +1938,7 @@ static int p9_next_unmasked_interrupt(CPUPPCState *env)
              * When PSSCR[EC] is set, LPCR[PECE] controls which interrupts can
              * wakeup the processor
              */
-            return p9_interrupt_powersave(env);
+            return p9_interrupt_powersave(env, pending_interrupts, lpcr);
         } else {
             /*
              * When it's clear, any system-caused exception exits power-saving
@@ -1944,14 +1949,14 @@ static int p9_next_unmasked_interrupt(CPUPPCState *env)
     }
 
     /* 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;
@@ -1959,18 +1964,18 @@ static int p9_next_unmasked_interrupt(CPUPPCState *env)
     }
 
     /* Hypervisor virtualization interrupt */
-    if (env->pending_interrupts & PPC_INTERRUPT_HVIRT) {
+    if (pending_interrupts & PPC_INTERRUPT_HVIRT) {
         /* LPCR will be clear when not supported so this will work */
-        bool hvice = !!(env->spr[SPR_LPCR] & LPCR_HVICE);
+        bool hvice = !!(lpcr & LPCR_HVICE);
         if ((msr_ee || !FIELD_EX64_HV(env->msr)) && hvice) {
             return PPC_INTERRUPT_HVIRT;
         }
     }
 
     /* 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))) ||
@@ -1980,20 +1985,20 @@ static int p9_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.
@@ -2020,7 +2025,8 @@ static int ppc_next_unmasked_interrupt(CPUPPCState *env)
     case POWERPC_EXCP_POWER9:
     case POWERPC_EXCP_POWER10:
     case POWERPC_EXCP_POWER11:
-        return p9_next_unmasked_interrupt(env);
+        return p9_next_unmasked_interrupt(env, env->pending_interrupts,
+                                          env->spr[SPR_LPCR]);
     default:
         break;
     }
-- 
2.45.2