[PATCH v3 15/59] target/arm/hvf: Simplify hvf_arm_get_host_cpu_features()

Philippe Mathieu-Daudé posted 59 patches 2 weeks, 3 days ago
Maintainers: Richard Henderson <richard.henderson@linaro.org>, Paolo Bonzini <pbonzini@redhat.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Cameron Esfahani <dirty@apple.com>, Roman Bolshakov <rbolshakov@ddn.com>, Phil Dennis-Jordan <phil@philjordan.eu>, Mads Ynddal <mads@ynddal.dk>, Peter Maydell <peter.maydell@linaro.org>, Alexander Graf <agraf@csgraf.de>, Stefan Hajnoczi <stefanha@redhat.com>
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[PATCH v3 15/59] target/arm/hvf: Simplify hvf_arm_get_host_cpu_features()
Posted by Philippe Mathieu-Daudé 2 weeks, 3 days ago
Use index in the structure, dereference &host_isar.idregs[] once.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 target/arm/hvf/hvf.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c
index 890e9266f93..dea1cb37d1f 100644
--- a/target/arm/hvf/hvf.c
+++ b/target/arm/hvf/hvf.c
@@ -743,21 +743,21 @@ static void clamp_id_aa64mmfr0_parange_to_ipa_size(ARMISARegisters *isar)
 static bool hvf_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
 {
     ARMISARegisters host_isar = {};
-    const struct isar_regs {
+    static const struct isar_regs {
         int reg;
-        uint64_t *val;
+        ARMIDRegisterIdx index;
     } regs[] = {
-        { HV_SYS_REG_ID_AA64PFR0_EL1, &host_isar.idregs[ID_AA64PFR0_EL1_IDX] },
-        { HV_SYS_REG_ID_AA64PFR1_EL1, &host_isar.idregs[ID_AA64PFR1_EL1_IDX] },
+        { HV_SYS_REG_ID_AA64PFR0_EL1, ID_AA64PFR0_EL1_IDX },
+        { HV_SYS_REG_ID_AA64PFR1_EL1, ID_AA64PFR1_EL1_IDX },
         /* Add ID_AA64PFR2_EL1 here when HVF supports it */
-        { HV_SYS_REG_ID_AA64DFR0_EL1, &host_isar.idregs[ID_AA64DFR0_EL1_IDX] },
-        { HV_SYS_REG_ID_AA64DFR1_EL1, &host_isar.idregs[ID_AA64DFR1_EL1_IDX] },
-        { HV_SYS_REG_ID_AA64ISAR0_EL1, &host_isar.idregs[ID_AA64ISAR0_EL1_IDX] },
-        { HV_SYS_REG_ID_AA64ISAR1_EL1, &host_isar.idregs[ID_AA64ISAR1_EL1_IDX] },
+        { HV_SYS_REG_ID_AA64DFR0_EL1, ID_AA64DFR0_EL1_IDX },
+        { HV_SYS_REG_ID_AA64DFR1_EL1, ID_AA64DFR1_EL1_IDX },
+        { HV_SYS_REG_ID_AA64ISAR0_EL1, ID_AA64ISAR0_EL1_IDX },
+        { HV_SYS_REG_ID_AA64ISAR1_EL1, ID_AA64ISAR1_EL1_IDX },
         /* Add ID_AA64ISAR2_EL1 here when HVF supports it */
-        { HV_SYS_REG_ID_AA64MMFR0_EL1, &host_isar.idregs[ID_AA64MMFR0_EL1_IDX] },
-        { HV_SYS_REG_ID_AA64MMFR1_EL1, &host_isar.idregs[ID_AA64MMFR1_EL1_IDX] },
-        { HV_SYS_REG_ID_AA64MMFR2_EL1, &host_isar.idregs[ID_AA64MMFR2_EL1_IDX] },
+        { HV_SYS_REG_ID_AA64MMFR0_EL1, ID_AA64MMFR0_EL1_IDX },
+        { HV_SYS_REG_ID_AA64MMFR1_EL1, ID_AA64MMFR1_EL1_IDX },
+        { HV_SYS_REG_ID_AA64MMFR2_EL1, ID_AA64MMFR2_EL1_IDX },
         /* Add ID_AA64MMFR3_EL1 here when HVF supports it */
     };
     hv_vcpu_t fd;
@@ -780,7 +780,8 @@ static bool hvf_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
     }
 
     for (i = 0; i < ARRAY_SIZE(regs); i++) {
-        r |= hv_vcpu_get_sys_reg(fd, regs[i].reg, regs[i].val);
+        r |= hv_vcpu_get_sys_reg(fd, regs[i].reg,
+                                 &host_isar.idregs[regs[i].index]);
     }
     r |= hv_vcpu_destroy(fd);
 
-- 
2.51.0


Re: [PATCH v3 15/59] target/arm/hvf: Simplify hvf_arm_get_host_cpu_features()
Posted by Richard Henderson 2 weeks, 3 days ago
On 10/28/25 06:41, Philippe Mathieu-Daudé wrote:
> Use index in the structure, dereference &host_isar.idregs[] once.
> 
> Suggested-by: Richard Henderson<richard.henderson@linaro.org>
> Signed-off-by: Philippe Mathieu-Daudé<philmd@linaro.org>
> ---
>   target/arm/hvf/hvf.c | 25 +++++++++++++------------
>   1 file changed, 13 insertions(+), 12 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~

Re: [PATCH v3 15/59] target/arm/hvf: Simplify hvf_arm_get_host_cpu_features()
Posted by Peter Maydell 2 weeks, 3 days ago
On Tue, 28 Oct 2025 at 05:53, Philippe Mathieu-Daudé <philmd@linaro.org> wrote:
>
> Use index in the structure, dereference &host_isar.idregs[] once.
>
> Suggested-by: Richard Henderson <richard.henderson@linaro.org>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>


Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM