commit 602f6e42cfbfe9278be34e9b91d2ceb695837e02
author Peter Maydell <peter.maydell@linaro.org> Thu Feb 28 10:55:16 2019 +0000
committer Peter Maydell <peter.maydell@linaro.org> Thu Feb 28 11:03:04 2019 +0000
tree fab04e997914a2856797c661155179c0d8ad0155
parent aab7a3786f085cb4c6842c3c8ea0c86e2c835248

target/arm: Use MVFR1 feature bits to gate A32/T32 FP16 instructions

Instead of gating the A32/T32 FP16 conversion instructions on
the ARM_FEATURE_VFP_FP16 flag, switch to our new approach of
looking at ID register bits. In this case MVFR1 fields FPHP
and SIMDHP indicate the presence of these insns.

This change doesn't alter behaviour for any of our CPUs.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20190222170936.13268-2-peter.maydell@linaro.org

target/arm/translate.c

diff --git a/target/arm/translate.c b/target/arm/translate.c
index c117579..b7702fb 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -3663,17 +3663,27 @@
                      * UNPREDICTABLE if bit 8 is set prior to ARMv8
                      * (we choose to UNDEF)
                      */
-                    if ((dp && !arm_dc_feature(s, ARM_FEATURE_V8)) ||
-                        !arm_dc_feature(s, ARM_FEATURE_VFP_FP16)) {
-                        return 1;
+                    if (dp) {
+                        if (!dc_isar_feature(aa32_fp16_dpconv, s)) {
+                            return 1;
+                        }
+                    } else {
+                        if (!dc_isar_feature(aa32_fp16_spconv, s)) {
+                            return 1;
+                        }
                     }
                     rm_is_dp = false;
                     break;
                 case 0x06: /* vcvtb.f16.f32, vcvtb.f16.f64 */
                 case 0x07: /* vcvtt.f16.f32, vcvtt.f16.f64 */
-                    if ((dp && !arm_dc_feature(s, ARM_FEATURE_V8)) ||
-                        !arm_dc_feature(s, ARM_FEATURE_VFP_FP16)) {
-                        return 1;
+                    if (dp) {
+                        if (!dc_isar_feature(aa32_fp16_dpconv, s)) {
+                            return 1;
+                        }
+                    } else {
+                        if (!dc_isar_feature(aa32_fp16_spconv, s)) {
+                            return 1;
+                        }
                     }
                     rd_is_dp = false;
                     break;
@@ -7876,7 +7886,7 @@
                     TCGv_ptr fpst;
                     TCGv_i32 ahp;
 
-                    if (!arm_dc_feature(s, ARM_FEATURE_VFP_FP16) ||
+                    if (!dc_isar_feature(aa32_fp16_spconv, s) ||
                         q || (rm & 1)) {
                         return 1;
                     }
@@ -7908,7 +7918,7 @@
                 {
                     TCGv_ptr fpst;
                     TCGv_i32 ahp;
-                    if (!arm_dc_feature(s, ARM_FEATURE_VFP_FP16) ||
+                    if (!dc_isar_feature(aa32_fp16_spconv, s) ||
                         q || (rd & 1)) {
                         return 1;
                     }