target/arm: Add ARM_FEATURE_V8_RDM

Not enabled anywhere yet.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180228193125.20577-2-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

linux-user/elfload.c

@@ -553,6 +553,7 @@ static uint32_t get_elf_hwcap(void)
     GET_FEATURE(ARM_FEATURE_V8_SHA512, ARM_HWCAP_A64_SHA512);
     GET_FEATURE(ARM_FEATURE_V8_FP16,
                 ARM_HWCAP_A64_FPHP | ARM_HWCAP_A64_ASIMDHP);
+    GET_FEATURE(ARM_FEATURE_V8_RDM, ARM_HWCAP_A64_ASIMDRDM);
 #undef GET_FEATURE
 
     return hwcaps;

target/arm/cpu.h

@@ -1433,6 +1433,7 @@ enum arm_features {
     ARM_FEATURE_V8_SHA3, /* implements SHA3 part of v8 Crypto Extensions */
     ARM_FEATURE_V8_SM3, /* implements SM3 part of v8 Crypto Extensions */
     ARM_FEATURE_V8_SM4, /* implements SM4 part of v8 Crypto Extensions */
+    ARM_FEATURE_V8_RDM, /* implements v8.1 simd round multiply */
     ARM_FEATURE_V8_FP16, /* implements v8.2 half-precision float */
 };