target/arm: Optimize cpu_mmu_index

We now cache the core mmu_idx in env->hflags.  Rather than recompute
from scratch, extract the field.  All of the uses of cpu_mmu_index
within target/arm are within helpers, and env->hflags is always stable
within a translation block from whence helpers are called.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200302175829.2183-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 13 insertions, 10 deletions

diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 0ae07a72e4..4ffd991b6f 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -2943,16 +2943,6 @@ typedef enum ARMMMUIdxBit {
 
 #define MMU_USER_IDX 0
 
-/**
- * cpu_mmu_index:
- * @env: The cpu environment
- * @ifetch: True for code access, false for data access.
- *
- * Return the core mmu index for the current translation regime.
- * This function is used by generic TCG code paths.
- */
-int cpu_mmu_index(CPUARMState *env, bool ifetch);
-
 /* Indexes used when registering address spaces with cpu_address_space_init */
 typedef enum ARMASIdx {
     ARMASIdx_NS = 0,
@@ -3232,6 +3222,19 @@ FIELD(TBFLAG_A64, BTYPE, 10, 2)         /* Not cached. */
 FIELD(TBFLAG_A64, TBID, 12, 2)
 FIELD(TBFLAG_A64, UNPRIV, 14, 1)
 
+/**
+ * cpu_mmu_index:
+ * @env: The cpu environment
+ * @ifetch: True for code access, false for data access.
+ *
+ * Return the core mmu index for the current translation regime.
+ * This function is used by generic TCG code paths.
+ */
+static inline int cpu_mmu_index(CPUARMState *env, bool ifetch)
+{
+    return FIELD_EX32(env->hflags, TBFLAG_ANY, MMUIDX);
+}
+
 static inline bool bswap_code(bool sctlr_b)
 {
 #ifdef CONFIG_USER_ONLY