target/arm: Hoist arm_is_el2_enabled check in sve_exception_el

This check is buried within arm_hcr_el2_eff(), but since we
have to have the explicit check for CPTR_EL2.TZ, we might as
well just check it once at the beginning of the block.

Once this is done, we can test HCR_EL2.{E2H,TGE} directly,
rather than going through arm_hcr_el2_eff().

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220607203306.657998-9-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/target/arm/helper.c b/target/arm/helper.c
index 40b60b1..61e8026 100644 (file)
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -6183,15 +6183,12 @@ int sve_exception_el(CPUARMState *env, int el)
         }
     }
 
-    /*
-     * CPTR_EL2 changes format with HCR_EL2.E2H (regardless of TGE).
-     */
-    if (el <= 2) {
-        uint64_t hcr_el2 = arm_hcr_el2_eff(env);
-        if (hcr_el2 & HCR_E2H) {
+    if (el <= 2 && arm_is_el2_enabled(env)) {
+        /* CPTR_EL2 changes format with HCR_EL2.E2H (regardless of TGE). */
+        if (env->cp15.hcr_el2 & HCR_E2H) {
             switch (FIELD_EX64(env->cp15.cptr_el[2], CPTR_EL2, ZEN)) {
             case 1:
-                if (el != 0 || !(hcr_el2 & HCR_TGE)) {
+                if (el != 0 || !(env->cp15.hcr_el2 & HCR_TGE)) {
                     break;
                 }
                 /* fall through */
@@ -6199,7 +6196,7 @@ int sve_exception_el(CPUARMState *env, int el)
             case 2:
                 return 2;
             }
-        } else if (arm_is_el2_enabled(env)) {
+        } else {
             if (FIELD_EX64(env->cp15.cptr_el[2], CPTR_EL2, TZ)) {
                 return 2;
             }