From dc1f2247ec88fc240ac1d5956bc5692cce3d86bc Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 25 Jun 2019 18:55:23 -0500 Subject: [PATCH] target/arm: Only implement doubles if the FPU supports them The architecture permits FPUs which have only single-precision support, not double-precision; Cortex-M4 and Cortex-M33 are both like that. Add the necessary checks on the MVFR0 FPDP field so that we UNDEF any double-precision instructions on CPUs like this. Note that even if FPDP==0 the insns like VMOV-to/from-gpreg, VLDM/VSTM, VLDR/VSTR which take double precision registers still exist. Backports commit 1120827fa182f0e76226df7ffe7a86598d1df54f from qemu --- qemu/target/arm/cpu.h | 6 +++ qemu/target/arm/translate-vfp.inc.c | 84 +++++++++++++++++++++++++++++ 2 files changed, 90 insertions(+) diff --git a/qemu/target/arm/cpu.h b/qemu/target/arm/cpu.h index b4ed4067..0bad697d 100644 --- a/qemu/target/arm/cpu.h +++ b/qemu/target/arm/cpu.h @@ -3339,6 +3339,12 @@ static inline bool isar_feature_aa32_fpshvec(const ARMISARegisters *id) return FIELD_EX64(id->mvfr0, MVFR0, FPSHVEC) > 0; } +static inline bool isar_feature_aa32_fpdp(const ARMISARegisters *id) +{ + /* Return true if CPU supports double precision floating point */ + return FIELD_EX64(id->mvfr0, MVFR0, FPDP) > 0; +} + /* * We always set the FP and SIMD FP16 fields to indicate identical * levels of support (assuming SIMD is implemented at all), so diff --git a/qemu/target/arm/translate-vfp.inc.c b/qemu/target/arm/translate-vfp.inc.c index 10a521d6..c57e5c85 100644 --- a/qemu/target/arm/translate-vfp.inc.c +++ b/qemu/target/arm/translate-vfp.inc.c @@ -209,6 +209,11 @@ static bool trans_VSEL(DisasContext *s, arg_VSEL *a) ((a->vm | a->vn | a->vd) & 0x10)) { return false; } + + if (dp && !dc_isar_feature(aa32_fpdp, s)) { + return false; + } + rd = a->vd; rn = a->vn; rm = a->vm; @@ -338,6 +343,11 @@ static bool trans_VMINMAXNM(DisasContext *s, arg_VMINMAXNM *a) ((a->vm | a->vn | a->vd) & 0x10)) { return false; } + + if (dp && !dc_isar_feature(aa32_fpdp, s)) { + return false; + } + rd = a->vd; rn = a->vn; rm = a->vm; @@ -420,6 +430,11 @@ static bool trans_VRINT(DisasContext *s, arg_VRINT *a) ((a->vm | a->vd) & 0x10)) { return false; } + + if (dp && !dc_isar_feature(aa32_fpdp, s)) { + return false; + } + rd = a->vd; rm = a->vm; @@ -479,6 +494,11 @@ static bool trans_VCVT(DisasContext *s, arg_VCVT *a) if (dp && !dc_isar_feature(aa32_fp_d32, s) && (a->vm & 0x10)) { return false; } + + if (dp && !dc_isar_feature(aa32_fpdp, s)) { + return false; + } + rd = a->vd; rm = a->vm; @@ -1320,6 +1340,10 @@ static bool do_vfp_3op_dp(DisasContext *s, VFPGen3OpDPFn *fn, return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!dc_isar_feature(aa32_fpshvec, s) && (veclen != 0 || s->vec_stride != 0)) { return false; @@ -1472,6 +1496,10 @@ static bool do_vfp_2op_dp(DisasContext *s, VFPGen2OpDPFn *fn, int vd, int vm) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -1765,6 +1793,10 @@ static bool trans_VFM_sp(DisasContext *s, arg_VFM_sp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -1926,6 +1958,10 @@ static bool trans_VMOV_imm_dp(DisasContext *s, arg_VMOV_imm_dp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!dc_isar_feature(aa32_fpshvec, s) && (veclen != 0 || s->vec_stride != 0)) { return false; @@ -2068,6 +2104,10 @@ static bool trans_VCMP_dp(DisasContext *s, arg_VCMP_dp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2139,6 +2179,10 @@ static bool trans_VCVT_f64_f16(DisasContext *s, arg_VCVT_f64_f16 *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2203,6 +2247,10 @@ static bool trans_VCVT_f16_f64(DisasContext *s, arg_VCVT_f16_f64 *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2261,6 +2309,10 @@ static bool trans_VRINTR_dp(DisasContext *s, arg_VRINTR_dp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2320,6 +2372,10 @@ static bool trans_VRINTZ_dp(DisasContext *s, arg_VRINTZ_dp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2377,6 +2433,10 @@ static bool trans_VRINTX_dp(DisasContext *s, arg_VRINTX_dp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2402,6 +2462,10 @@ static bool trans_VCVT_sp(DisasContext *s, arg_VCVT_sp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2427,6 +2491,10 @@ static bool trans_VCVT_dp(DisasContext *s, arg_VCVT_dp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2479,6 +2547,10 @@ static bool trans_VCVT_int_dp(DisasContext *s, arg_VCVT_int_dp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2516,6 +2588,10 @@ static bool trans_VJCVT(DisasContext *s, arg_VJCVT *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2607,6 +2683,10 @@ static bool trans_VCVT_fix_dp(DisasContext *s, arg_VCVT_fix_dp *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; } @@ -2701,6 +2781,10 @@ static bool trans_VCVT_dp_int(DisasContext *s, arg_VCVT_dp_int *a) return false; } + if (!dc_isar_feature(aa32_fpdp, s)) { + return false; + } + if (!vfp_access_check(s)) { return true; }