target/arm: convert conversion helpers to fpst/ahp_flag
Instead of passing env and leaving it up to the helper to get the right fpstatus we pass it explicitly. There was already a get_fpstatus helper for neon for the 32 bit code. We also add an get_ahp_flag() for passing the state of the alternative FP16 format flag. This leaves scope for later tracking the AHP state in translation flags. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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@ -11540,64 +11540,24 @@ uint32_t HELPER(set_neon_rmode)(uint32_t rmode, CPUARMState *env)
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}
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/* Half precision conversions. */
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static float32 do_fcvt_f16_to_f32(uint32_t a, CPUARMState *env, float_status *s)
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float32 HELPER(vfp_fcvt_f16_to_f32)(float16 a, void *fpstp, uint32_t ahp_mode)
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{
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int ieee = (env->vfp.xregs[ARM_VFP_FPSCR] & (1 << 26)) == 0;
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float32 r = float16_to_float32(make_float16(a), ieee, s);
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if (ieee) {
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return float32_maybe_silence_nan(r, s);
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}
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return r;
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return float16_to_float32(a, !ahp_mode, fpstp);
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}
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static uint32_t do_fcvt_f32_to_f16(float32 a, CPUARMState *env, float_status *s)
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float16 HELPER(vfp_fcvt_f32_to_f16)(float32 a, void *fpstp, uint32_t ahp_mode)
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{
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int ieee = (env->vfp.xregs[ARM_VFP_FPSCR] & (1 << 26)) == 0;
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float16 r = float32_to_float16(a, ieee, s);
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if (ieee) {
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r = float16_maybe_silence_nan(r, s);
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}
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return float16_val(r);
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return float32_to_float16(a, !ahp_mode, fpstp);
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}
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float32 HELPER(neon_fcvt_f16_to_f32)(uint32_t a, CPUARMState *env)
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float64 HELPER(vfp_fcvt_f16_to_f64)(float16 a, void *fpstp, uint32_t ahp_mode)
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{
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return do_fcvt_f16_to_f32(a, env, &env->vfp.standard_fp_status);
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return float16_to_float64(a, !ahp_mode, fpstp);
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}
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uint32_t HELPER(neon_fcvt_f32_to_f16)(float32 a, CPUARMState *env)
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float16 HELPER(vfp_fcvt_f64_to_f16)(float64 a, void *fpstp, uint32_t ahp_mode)
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{
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return do_fcvt_f32_to_f16(a, env, &env->vfp.standard_fp_status);
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}
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float32 HELPER(vfp_fcvt_f16_to_f32)(uint32_t a, CPUARMState *env)
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{
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return do_fcvt_f16_to_f32(a, env, &env->vfp.fp_status);
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}
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uint32_t HELPER(vfp_fcvt_f32_to_f16)(float32 a, CPUARMState *env)
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{
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return do_fcvt_f32_to_f16(a, env, &env->vfp.fp_status);
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}
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float64 HELPER(vfp_fcvt_f16_to_f64)(uint32_t a, CPUARMState *env)
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{
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int ieee = (env->vfp.xregs[ARM_VFP_FPSCR] & (1 << 26)) == 0;
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float64 r = float16_to_float64(make_float16(a), ieee, &env->vfp.fp_status);
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if (ieee) {
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return float64_maybe_silence_nan(r, &env->vfp.fp_status);
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}
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return r;
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}
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uint32_t HELPER(vfp_fcvt_f64_to_f16)(float64 a, CPUARMState *env)
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{
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int ieee = (env->vfp.xregs[ARM_VFP_FPSCR] & (1 << 26)) == 0;
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float16 r = float64_to_float16(a, ieee, &env->vfp.fp_status);
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if (ieee) {
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r = float16_maybe_silence_nan(r, &env->vfp.fp_status);
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}
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return float16_val(r);
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return float64_to_float16(a, !ahp_mode, fpstp);
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}
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#define float32_two make_float32(0x40000000)
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@ -187,12 +187,10 @@ DEF_HELPER_3(vfp_uqtoh, f16, i64, i32, ptr)
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DEF_HELPER_FLAGS_2(set_rmode, TCG_CALL_NO_RWG, i32, i32, ptr)
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DEF_HELPER_FLAGS_2(set_neon_rmode, TCG_CALL_NO_RWG, i32, i32, env)
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DEF_HELPER_2(vfp_fcvt_f16_to_f32, f32, i32, env)
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DEF_HELPER_2(vfp_fcvt_f32_to_f16, i32, f32, env)
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DEF_HELPER_2(neon_fcvt_f16_to_f32, f32, i32, env)
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DEF_HELPER_2(neon_fcvt_f32_to_f16, i32, f32, env)
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DEF_HELPER_FLAGS_2(vfp_fcvt_f16_to_f64, TCG_CALL_NO_RWG, f64, i32, env)
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DEF_HELPER_FLAGS_2(vfp_fcvt_f64_to_f16, TCG_CALL_NO_RWG, i32, f64, env)
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DEF_HELPER_FLAGS_3(vfp_fcvt_f16_to_f32, TCG_CALL_NO_RWG, f32, f16, ptr, i32)
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DEF_HELPER_FLAGS_3(vfp_fcvt_f32_to_f16, TCG_CALL_NO_RWG, f16, f32, ptr, i32)
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DEF_HELPER_FLAGS_3(vfp_fcvt_f16_to_f64, TCG_CALL_NO_RWG, f64, f16, ptr, i32)
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DEF_HELPER_FLAGS_3(vfp_fcvt_f64_to_f16, TCG_CALL_NO_RWG, f16, f64, ptr, i32)
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DEF_HELPER_4(vfp_muladdd, f64, f64, f64, f64, ptr)
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DEF_HELPER_4(vfp_muladds, f32, f32, f32, f32, ptr)
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@ -5147,10 +5147,15 @@ static void handle_fp_fcvt(DisasContext *s, int opcode,
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} else {
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/* Single to half */
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TCGv_i32 tcg_rd = tcg_temp_new_i32();
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gen_helper_vfp_fcvt_f32_to_f16(tcg_rd, tcg_rn, cpu_env);
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TCGv_i32 ahp = get_ahp_flag();
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TCGv_ptr fpst = get_fpstatus_ptr(false);
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gen_helper_vfp_fcvt_f32_to_f16(tcg_rd, tcg_rn, fpst, ahp);
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/* write_fp_sreg is OK here because top half of tcg_rd is zero */
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write_fp_sreg(s, rd, tcg_rd);
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tcg_temp_free_i32(tcg_rd);
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tcg_temp_free_i32(ahp);
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tcg_temp_free_ptr(fpst);
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}
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tcg_temp_free_i32(tcg_rn);
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break;
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@ -5163,9 +5168,13 @@ static void handle_fp_fcvt(DisasContext *s, int opcode,
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/* Double to single */
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gen_helper_vfp_fcvtsd(tcg_rd, tcg_rn, cpu_env);
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} else {
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TCGv_ptr fpst = get_fpstatus_ptr(false);
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TCGv_i32 ahp = get_ahp_flag();
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/* Double to half */
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gen_helper_vfp_fcvt_f64_to_f16(tcg_rd, tcg_rn, cpu_env);
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gen_helper_vfp_fcvt_f64_to_f16(tcg_rd, tcg_rn, fpst, ahp);
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/* write_fp_sreg is OK here because top half of tcg_rd is zero */
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tcg_temp_free_ptr(fpst);
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tcg_temp_free_i32(ahp);
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}
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write_fp_sreg(s, rd, tcg_rd);
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tcg_temp_free_i32(tcg_rd);
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@ -5175,17 +5184,21 @@ static void handle_fp_fcvt(DisasContext *s, int opcode,
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case 0x3:
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{
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TCGv_i32 tcg_rn = read_fp_sreg(s, rn);
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TCGv_ptr tcg_fpst = get_fpstatus_ptr(false);
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TCGv_i32 tcg_ahp = get_ahp_flag();
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tcg_gen_ext16u_i32(tcg_rn, tcg_rn);
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if (dtype == 0) {
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/* Half to single */
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TCGv_i32 tcg_rd = tcg_temp_new_i32();
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gen_helper_vfp_fcvt_f16_to_f32(tcg_rd, tcg_rn, cpu_env);
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gen_helper_vfp_fcvt_f16_to_f32(tcg_rd, tcg_rn, tcg_fpst, tcg_ahp);
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write_fp_sreg(s, rd, tcg_rd);
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tcg_temp_free_ptr(tcg_fpst);
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tcg_temp_free_i32(tcg_ahp);
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tcg_temp_free_i32(tcg_rd);
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} else {
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/* Half to double */
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TCGv_i64 tcg_rd = tcg_temp_new_i64();
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gen_helper_vfp_fcvt_f16_to_f64(tcg_rd, tcg_rn, cpu_env);
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gen_helper_vfp_fcvt_f16_to_f64(tcg_rd, tcg_rn, tcg_fpst, tcg_ahp);
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write_fp_dreg(s, rd, tcg_rd);
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tcg_temp_free_i64(tcg_rd);
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}
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@ -9053,12 +9066,17 @@ static void handle_2misc_narrow(DisasContext *s, bool scalar,
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} else {
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TCGv_i32 tcg_lo = tcg_temp_new_i32();
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TCGv_i32 tcg_hi = tcg_temp_new_i32();
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TCGv_ptr fpst = get_fpstatus_ptr(false);
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TCGv_i32 ahp = get_ahp_flag();
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tcg_gen_extr_i64_i32(tcg_lo, tcg_hi, tcg_op);
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gen_helper_vfp_fcvt_f32_to_f16(tcg_lo, tcg_lo, cpu_env);
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gen_helper_vfp_fcvt_f32_to_f16(tcg_hi, tcg_hi, cpu_env);
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gen_helper_vfp_fcvt_f32_to_f16(tcg_lo, tcg_lo, fpst, ahp);
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gen_helper_vfp_fcvt_f32_to_f16(tcg_hi, tcg_hi, fpst, ahp);
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tcg_gen_deposit_i32(tcg_res[pass], tcg_lo, tcg_hi, 16, 16);
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tcg_temp_free_i32(tcg_lo);
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tcg_temp_free_i32(tcg_hi);
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tcg_temp_free_ptr(fpst);
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tcg_temp_free_i32(ahp);
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}
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break;
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case 0x56: /* FCVTXN, FCVTXN2 */
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@ -11532,18 +11550,23 @@ static void handle_2misc_widening(DisasContext *s, int opcode, bool is_q,
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/* 16 -> 32 bit fp conversion */
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int srcelt = is_q ? 4 : 0;
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TCGv_i32 tcg_res[4];
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TCGv_ptr fpst = get_fpstatus_ptr(false);
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TCGv_i32 ahp = get_ahp_flag();
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for (pass = 0; pass < 4; pass++) {
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tcg_res[pass] = tcg_temp_new_i32();
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read_vec_element_i32(s, tcg_res[pass], rn, srcelt + pass, MO_16);
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gen_helper_vfp_fcvt_f16_to_f32(tcg_res[pass], tcg_res[pass],
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cpu_env);
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fpst, ahp);
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}
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for (pass = 0; pass < 4; pass++) {
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write_vec_element_i32(s, tcg_res[pass], rd, pass, MO_32);
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tcg_temp_free_i32(tcg_res[pass]);
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}
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tcg_temp_free_ptr(fpst);
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tcg_temp_free_i32(ahp);
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}
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}
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@ -3824,38 +3824,56 @@ static int disas_vfp_insn(DisasContext *s, uint32_t insn)
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gen_vfp_sqrt(dp);
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break;
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case 4: /* vcvtb.f32.f16, vcvtb.f64.f16 */
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{
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TCGv_ptr fpst = get_fpstatus_ptr(false);
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TCGv_i32 ahp_mode = get_ahp_flag();
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tmp = gen_vfp_mrs();
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tcg_gen_ext16u_i32(tmp, tmp);
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if (dp) {
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gen_helper_vfp_fcvt_f16_to_f64(cpu_F0d, tmp,
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cpu_env);
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fpst, ahp_mode);
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} else {
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gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp,
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cpu_env);
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fpst, ahp_mode);
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}
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tcg_temp_free_i32(ahp_mode);
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tcg_temp_free_ptr(fpst);
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tcg_temp_free_i32(tmp);
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break;
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}
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case 5: /* vcvtt.f32.f16, vcvtt.f64.f16 */
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{
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TCGv_ptr fpst = get_fpstatus_ptr(false);
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TCGv_i32 ahp = get_ahp_flag();
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tmp = gen_vfp_mrs();
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tcg_gen_shri_i32(tmp, tmp, 16);
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if (dp) {
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gen_helper_vfp_fcvt_f16_to_f64(cpu_F0d, tmp,
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cpu_env);
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fpst, ahp);
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} else {
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gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp,
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cpu_env);
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fpst, ahp);
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}
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tcg_temp_free_i32(tmp);
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tcg_temp_free_i32(ahp);
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tcg_temp_free_ptr(fpst);
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break;
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}
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case 6: /* vcvtb.f16.f32, vcvtb.f16.f64 */
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{
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TCGv_ptr fpst = get_fpstatus_ptr(false);
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TCGv_i32 ahp = get_ahp_flag();
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tmp = tcg_temp_new_i32();
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if (dp) {
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gen_helper_vfp_fcvt_f64_to_f16(tmp, cpu_F0d,
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cpu_env);
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fpst, ahp);
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} else {
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gen_helper_vfp_fcvt_f32_to_f16(tmp, cpu_F0s,
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cpu_env);
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fpst, ahp);
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}
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tcg_temp_free_i32(ahp);
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tcg_temp_free_ptr(fpst);
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gen_mov_F0_vreg(0, rd);
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tmp2 = gen_vfp_mrs();
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tcg_gen_andi_i32(tmp2, tmp2, 0xffff0000);
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@ -3863,15 +3881,21 @@ static int disas_vfp_insn(DisasContext *s, uint32_t insn)
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tcg_temp_free_i32(tmp2);
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gen_vfp_msr(tmp);
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break;
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}
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case 7: /* vcvtt.f16.f32, vcvtt.f16.f64 */
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{
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TCGv_ptr fpst = get_fpstatus_ptr(false);
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TCGv_i32 ahp = get_ahp_flag();
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tmp = tcg_temp_new_i32();
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if (dp) {
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gen_helper_vfp_fcvt_f64_to_f16(tmp, cpu_F0d,
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cpu_env);
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fpst, ahp);
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} else {
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gen_helper_vfp_fcvt_f32_to_f16(tmp, cpu_F0s,
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cpu_env);
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fpst, ahp);
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}
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tcg_temp_free_i32(ahp);
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tcg_temp_free_ptr(fpst);
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tcg_gen_shli_i32(tmp, tmp, 16);
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gen_mov_F0_vreg(0, rd);
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tmp2 = gen_vfp_mrs();
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@ -3880,6 +3904,7 @@ static int disas_vfp_insn(DisasContext *s, uint32_t insn)
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tcg_temp_free_i32(tmp2);
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gen_vfp_msr(tmp);
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break;
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}
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case 8: /* cmp */
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gen_vfp_cmp(dp);
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break;
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@ -7222,53 +7247,70 @@ static int disas_neon_data_insn(DisasContext *s, uint32_t insn)
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}
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break;
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case NEON_2RM_VCVT_F16_F32:
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{
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TCGv_ptr fpst;
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TCGv_i32 ahp;
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if (!arm_dc_feature(s, ARM_FEATURE_VFP_FP16) ||
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q || (rm & 1)) {
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return 1;
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}
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tmp = tcg_temp_new_i32();
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tmp2 = tcg_temp_new_i32();
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fpst = get_fpstatus_ptr(true);
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ahp = get_ahp_flag();
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tcg_gen_ld_f32(cpu_F0s, cpu_env, neon_reg_offset(rm, 0));
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gen_helper_neon_fcvt_f32_to_f16(tmp, cpu_F0s, cpu_env);
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gen_helper_vfp_fcvt_f32_to_f16(tmp, cpu_F0s, fpst, ahp);
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tcg_gen_ld_f32(cpu_F0s, cpu_env, neon_reg_offset(rm, 1));
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gen_helper_neon_fcvt_f32_to_f16(tmp2, cpu_F0s, cpu_env);
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gen_helper_vfp_fcvt_f32_to_f16(tmp2, cpu_F0s, fpst, ahp);
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tcg_gen_shli_i32(tmp2, tmp2, 16);
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tcg_gen_or_i32(tmp2, tmp2, tmp);
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tcg_gen_ld_f32(cpu_F0s, cpu_env, neon_reg_offset(rm, 2));
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gen_helper_neon_fcvt_f32_to_f16(tmp, cpu_F0s, cpu_env);
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gen_helper_vfp_fcvt_f32_to_f16(tmp, cpu_F0s, fpst, ahp);
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tcg_gen_ld_f32(cpu_F0s, cpu_env, neon_reg_offset(rm, 3));
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neon_store_reg(rd, 0, tmp2);
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tmp2 = tcg_temp_new_i32();
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gen_helper_neon_fcvt_f32_to_f16(tmp2, cpu_F0s, cpu_env);
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gen_helper_vfp_fcvt_f32_to_f16(tmp2, cpu_F0s, fpst, ahp);
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tcg_gen_shli_i32(tmp2, tmp2, 16);
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tcg_gen_or_i32(tmp2, tmp2, tmp);
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neon_store_reg(rd, 1, tmp2);
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tcg_temp_free_i32(tmp);
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tcg_temp_free_i32(ahp);
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tcg_temp_free_ptr(fpst);
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break;
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}
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case NEON_2RM_VCVT_F32_F16:
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{
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TCGv_ptr fpst;
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TCGv_i32 ahp;
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if (!arm_dc_feature(s, ARM_FEATURE_VFP_FP16) ||
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q || (rd & 1)) {
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return 1;
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}
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fpst = get_fpstatus_ptr(true);
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ahp = get_ahp_flag();
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tmp3 = tcg_temp_new_i32();
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tmp = neon_load_reg(rm, 0);
|
||||
tmp2 = neon_load_reg(rm, 1);
|
||||
tcg_gen_ext16u_i32(tmp3, tmp);
|
||||
gen_helper_neon_fcvt_f16_to_f32(cpu_F0s, tmp3, cpu_env);
|
||||
gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp3, fpst, ahp);
|
||||
tcg_gen_st_f32(cpu_F0s, cpu_env, neon_reg_offset(rd, 0));
|
||||
tcg_gen_shri_i32(tmp3, tmp, 16);
|
||||
gen_helper_neon_fcvt_f16_to_f32(cpu_F0s, tmp3, cpu_env);
|
||||
gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp3, fpst, ahp);
|
||||
tcg_gen_st_f32(cpu_F0s, cpu_env, neon_reg_offset(rd, 1));
|
||||
tcg_temp_free_i32(tmp);
|
||||
tcg_gen_ext16u_i32(tmp3, tmp2);
|
||||
gen_helper_neon_fcvt_f16_to_f32(cpu_F0s, tmp3, cpu_env);
|
||||
gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp3, fpst, ahp);
|
||||
tcg_gen_st_f32(cpu_F0s, cpu_env, neon_reg_offset(rd, 2));
|
||||
tcg_gen_shri_i32(tmp3, tmp2, 16);
|
||||
gen_helper_neon_fcvt_f16_to_f32(cpu_F0s, tmp3, cpu_env);
|
||||
gen_helper_vfp_fcvt_f16_to_f32(cpu_F0s, tmp3, fpst, ahp);
|
||||
tcg_gen_st_f32(cpu_F0s, cpu_env, neon_reg_offset(rd, 3));
|
||||
tcg_temp_free_i32(tmp2);
|
||||
tcg_temp_free_i32(tmp3);
|
||||
tcg_temp_free_i32(ahp);
|
||||
tcg_temp_free_ptr(fpst);
|
||||
break;
|
||||
}
|
||||
case NEON_2RM_AESE: case NEON_2RM_AESMC:
|
||||
if (!arm_dc_feature(s, ARM_FEATURE_V8_AES)
|
||||
|| ((rm | rd) & 1)) {
|
||||
|
@ -177,4 +177,16 @@ void arm_free_cc(DisasCompare *cmp);
|
||||
void arm_jump_cc(DisasCompare *cmp, TCGLabel *label);
|
||||
void arm_gen_test_cc(int cc, TCGLabel *label);
|
||||
|
||||
/* Return state of Alternate Half-precision flag, caller frees result */
|
||||
static inline TCGv_i32 get_ahp_flag(void)
|
||||
{
|
||||
TCGv_i32 ret = tcg_temp_new_i32();
|
||||
|
||||
tcg_gen_ld_i32(ret, cpu_env,
|
||||
offsetof(CPUARMState, vfp.xregs[ARM_VFP_FPSCR]));
|
||||
tcg_gen_extract_i32(ret, ret, 26, 1);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
#endif /* TARGET_ARM_TRANSLATE_H */
|
||||
|
Loading…
Reference in New Issue
Block a user