target/arm: Split out rebuild_hflags_a64

Create a function to compute the values of the TBFLAG_A64 bits
that will be cached.  For now, the env->hflags variable is not
used, and the results are fed back to cpu_get_tb_cpu_state.

Note that not all BTI related flags are cached, so we have to
test the BTI feature twice -- once for those bits moved out to
rebuild_hflags_a64 and once for those bits that remain in
cpu_get_tb_cpu_state.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20191023150057.25731-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 66 insertions, 59 deletions

diff --git a/target/arm/helper.c b/target/arm/helper.c
index 8829d91ae1..69da04786e 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -11070,76 +11070,83 @@ static uint32_t rebuild_hflags_common(CPUARMState *env, int fp_el,
     return flags;
 }
 
-void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
-                          target_ulong *cs_base, uint32_t *pflags)
+static uint32_t rebuild_hflags_a64(CPUARMState *env, int el, int fp_el,
+                                   ARMMMUIdx mmu_idx)
 {
-    ARMMMUIdx mmu_idx = arm_mmu_idx(env);
-    int current_el = arm_current_el(env);
-    int fp_el = fp_exception_el(env, current_el);
+    ARMMMUIdx stage1 = stage_1_mmu_idx(mmu_idx);
+    ARMVAParameters p0 = aa64_va_parameters_both(env, 0, stage1);
     uint32_t flags = 0;
+    uint64_t sctlr;
+    int tbii, tbid;
 
-    if (is_a64(env)) {
-        ARMCPU *cpu = env_archcpu(env);
-        uint64_t sctlr;
+    flags = FIELD_DP32(flags, TBFLAG_ANY, AARCH64_STATE, 1);
 
-        *pc = env->pc;
-        flags = FIELD_DP32(flags, TBFLAG_ANY, AARCH64_STATE, 1);
+    /* FIXME: ARMv8.1-VHE S2 translation regime.  */
+    if (regime_el(env, stage1) < 2) {
+        ARMVAParameters p1 = aa64_va_parameters_both(env, -1, stage1);
+        tbid = (p1.tbi << 1) | p0.tbi;
+        tbii = tbid & ~((p1.tbid << 1) | p0.tbid);
+    } else {
+        tbid = p0.tbi;
+        tbii = tbid & !p0.tbid;
+    }
 
-        /* Get control bits for tagged addresses.  */
-        {
-            ARMMMUIdx stage1 = stage_1_mmu_idx(mmu_idx);
-            ARMVAParameters p0 = aa64_va_parameters_both(env, 0, stage1);
-            int tbii, tbid;
-
-            /* FIXME: ARMv8.1-VHE S2 translation regime.  */
-            if (regime_el(env, stage1) < 2) {
-                ARMVAParameters p1 = aa64_va_parameters_both(env, -1, stage1);
-                tbid = (p1.tbi << 1) | p0.tbi;
-                tbii = tbid & ~((p1.tbid << 1) | p0.tbid);
-            } else {
-                tbid = p0.tbi;
-                tbii = tbid & !p0.tbid;
-            }
+    flags = FIELD_DP32(flags, TBFLAG_A64, TBII, tbii);
+    flags = FIELD_DP32(flags, TBFLAG_A64, TBID, tbid);
+
+    if (cpu_isar_feature(aa64_sve, env_archcpu(env))) {
+        int sve_el = sve_exception_el(env, el);
+        uint32_t zcr_len;
 
-            flags = FIELD_DP32(flags, TBFLAG_A64, TBII, tbii);
-            flags = FIELD_DP32(flags, TBFLAG_A64, TBID, tbid);
+        /*
+         * If SVE is disabled, but FP is enabled,
+         * then the effective len is 0.
+         */
+        if (sve_el != 0 && fp_el == 0) {
+            zcr_len = 0;
+        } else {
+            zcr_len = sve_zcr_len_for_el(env, el);
         }
+        flags = FIELD_DP32(flags, TBFLAG_A64, SVEEXC_EL, sve_el);
+        flags = FIELD_DP32(flags, TBFLAG_A64, ZCR_LEN, zcr_len);
+    }
 
-        if (cpu_isar_feature(aa64_sve, cpu)) {
-            int sve_el = sve_exception_el(env, current_el);
-            uint32_t zcr_len;
+    sctlr = arm_sctlr(env, el);
 
-            /* If SVE is disabled, but FP is enabled,
-             * then the effective len is 0.
-             */
-            if (sve_el != 0 && fp_el == 0) {
-                zcr_len = 0;
-            } else {
-                zcr_len = sve_zcr_len_for_el(env, current_el);
-            }
-            flags = FIELD_DP32(flags, TBFLAG_A64, SVEEXC_EL, sve_el);
-            flags = FIELD_DP32(flags, TBFLAG_A64, ZCR_LEN, zcr_len);
+    if (cpu_isar_feature(aa64_pauth, env_archcpu(env))) {
+        /*
+         * In order to save space in flags, we record only whether
+         * pauth is "inactive", meaning all insns are implemented as
+         * a nop, or "active" when some action must be performed.
+         * The decision of which action to take is left to a helper.
+         */
+        if (sctlr & (SCTLR_EnIA | SCTLR_EnIB | SCTLR_EnDA | SCTLR_EnDB)) {
+            flags = FIELD_DP32(flags, TBFLAG_A64, PAUTH_ACTIVE, 1);
         }
+    }
 
-        sctlr = arm_sctlr(env, current_el);
-
-        if (cpu_isar_feature(aa64_pauth, cpu)) {
-            /*
-             * In order to save space in flags, we record only whether
-             * pauth is "inactive", meaning all insns are implemented as
-             * a nop, or "active" when some action must be performed.
-             * The decision of which action to take is left to a helper.
-             */
-            if (sctlr & (SCTLR_EnIA | SCTLR_EnIB | SCTLR_EnDA | SCTLR_EnDB)) {
-                flags = FIELD_DP32(flags, TBFLAG_A64, PAUTH_ACTIVE, 1);
-            }
+    if (cpu_isar_feature(aa64_bti, env_archcpu(env))) {
+        /* Note that SCTLR_EL[23].BT == SCTLR_BT1.  */
+        if (sctlr & (el == 0 ? SCTLR_BT0 : SCTLR_BT1)) {
+            flags = FIELD_DP32(flags, TBFLAG_A64, BT, 1);
         }
+    }
 
-        if (cpu_isar_feature(aa64_bti, cpu)) {
-            /* Note that SCTLR_EL[23].BT == SCTLR_BT1.  */
-            if (sctlr & (current_el == 0 ? SCTLR_BT0 : SCTLR_BT1)) {
-                flags = FIELD_DP32(flags, TBFLAG_A64, BT, 1);
-            }
+    return rebuild_hflags_common(env, fp_el, mmu_idx, flags);
+}
+
+void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
+                          target_ulong *cs_base, uint32_t *pflags)
+{
+    ARMMMUIdx mmu_idx = arm_mmu_idx(env);
+    int current_el = arm_current_el(env);
+    int fp_el = fp_exception_el(env, current_el);
+    uint32_t flags = 0;
+
+    if (is_a64(env)) {
+        *pc = env->pc;
+        flags = rebuild_hflags_a64(env, current_el, fp_el, mmu_idx);
+        if (cpu_isar_feature(aa64_bti, env_archcpu(env))) {
             flags = FIELD_DP32(flags, TBFLAG_A64, BTYPE, env->btype);
         }
     } else {
@@ -11159,9 +11166,9 @@ void cpu_get_tb_cpu_state(CPUARMState *env, target_ulong *pc,
             flags = FIELD_DP32(flags, TBFLAG_A32,
                                XSCALE_CPAR, env->cp15.c15_cpar);
         }
-    }
 
-    flags = rebuild_hflags_common(env, fp_el, mmu_idx, flags);
+        flags = rebuild_hflags_common(env, fp_el, mmu_idx, flags);
+    }
 
     /* The SS_ACTIVE and PSTATE_SS bits correspond to the state machine
      * states defined in the ARM ARM for software singlestep: