[PULL,41/72] target/ppc/mmu_common.c: Move calculation of a value closer to its usage

Commit Message

Nicholas Piggin May 23, 2024, 11:07 p.m. UTC

From: BALATON Zoltan <[e-mail]>

In mmubooke_check_tlb() and mmubooke206_check_tlb() prot2 is
calculated first but only used after an unrelated check that can
return before tha value is used. Move the calculation after the check,
closer to where it is used, to keep them together and avoid computing
it when not needed.

Reviewed-by: Nicholas Piggin <[e-mail]>
Signed-off-by: BALATON Zoltan <[e-mail]>
Signed-off-by: Nicholas Piggin <[e-mail]>
---
 target/ppc/mmu_common.c | 36 +++++++++++++++++-------------------
 1 file changed, 17 insertions(+), 19 deletions(-)

Patch

diff --git a/target/ppc/mmu_common.c b/target/ppc/mmu_common.c
index 4fde7fd3bf..f79e390306 100644
--- a/target/ppc/mmu_common.c
+++ b/target/ppc/mmu_common.c
@@ -635,12 +635,6 @@  static int mmubooke_check_tlb(CPUPPCState *env, ppcemb_tlb_t *tlb,
         return -1;
     }
 
-    if (FIELD_EX64(env->msr, MSR, PR)) {
-        prot2 = tlb->prot & 0xF;
-    } else {
-        prot2 = (tlb->prot >> 4) & 0xF;
-    }
-
     /* Check the address space */
     if ((access_type == MMU_INST_FETCH ?
         FIELD_EX64(env->msr, MSR, IR) :
@@ -649,6 +643,11 @@  static int mmubooke_check_tlb(CPUPPCState *env, ppcemb_tlb_t *tlb,
         return -1;
     }
 
+    if (FIELD_EX64(env->msr, MSR, PR)) {
+        prot2 = tlb->prot & 0xF;
+    } else {
+        prot2 = (tlb->prot >> 4) & 0xF;
+    }
     *prot = prot2;
     if (prot2 & prot_for_access_type(access_type)) {
         qemu_log_mask(CPU_LOG_MMU, "%s: good TLB!\n", __func__);
@@ -830,6 +829,18 @@  static int mmubooke206_check_tlb(CPUPPCState *env, ppcmas_tlb_t *tlb,
 
 found_tlb:
 
+    /* Check the address space and permissions */
+    if (access_type == MMU_INST_FETCH) {
+        /* There is no way to fetch code using epid load */
+        assert(!use_epid);
+        as = FIELD_EX64(env->msr, MSR, IR);
+    }
+
+    if (as != ((tlb->mas1 & MAS1_TS) >> MAS1_TS_SHIFT)) {
+        qemu_log_mask(CPU_LOG_MMU, "%s: AS doesn't match\n", __func__);
+        return -1;
+    }
+
     if (pr) {
         if (tlb->mas7_3 & MAS3_UR) {
             prot2 |= PAGE_READ;
@@ -851,19 +862,6 @@  found_tlb:
             prot2 |= PAGE_EXEC;
         }
     }
-
-    /* Check the address space and permissions */
-    if (access_type == MMU_INST_FETCH) {
-        /* There is no way to fetch code using epid load */
-        assert(!use_epid);
-        as = FIELD_EX64(env->msr, MSR, IR);
-    }
-
-    if (as != ((tlb->mas1 & MAS1_TS) >> MAS1_TS_SHIFT)) {
-        qemu_log_mask(CPU_LOG_MMU, "%s: AS doesn't match\n", __func__);
-        return -1;
-    }
-
     *prot = prot2;
     if (prot2 & prot_for_access_type(access_type)) {
         qemu_log_mask(CPU_LOG_MMU, "%s: good TLB!\n", __func__);