Commit 7a192925 authored by Alex Bennée's avatar Alex Bennée Committed by Peter Maydell
Browse files

target/arm: Implement FCMP for fp16 



These where missed out from the rest of the half-precision work.

Cc: qemu-stable@nongnu.org
Reviewed-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: default avatarAlex Bennée <alex.bennee@linaro.org>
Tested-by: default avatarAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: default avatarRichard Henderson <richard.henderson@linaro.org>
Message-id: 20180512003217.9105-9-richard.henderson@linaro.org
[rth: Diagnose lack of FP16 before fp_access_check]
Signed-off-by: default avatarRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
parent 95f9864f

target/arm/helper-a64.c

+10 −0
Original line number Diff line number Diff line
@@ -85,6 +85,16 @@ static inline uint32_t float_rel_to_flags(int res) 
    return flags;

}



uint64_t HELPER(vfp_cmph_a64)(float16 x, float16 y, void *fp_status)

{

    return float_rel_to_flags(float16_compare_quiet(x, y, fp_status));

}



uint64_t HELPER(vfp_cmpeh_a64)(float16 x, float16 y, void *fp_status)

{

    return float_rel_to_flags(float16_compare(x, y, fp_status));

}



uint64_t HELPER(vfp_cmps_a64)(float32 x, float32 y, void *fp_status)

{

    return float_rel_to_flags(float32_compare_quiet(x, y, fp_status));

target/arm/helper-a64.h

+2 −0
Original line number Diff line number Diff line
@@ -19,6 +19,8 @@ 
DEF_HELPER_FLAGS_2(udiv64, TCG_CALL_NO_RWG_SE, i64, i64, i64)

DEF_HELPER_FLAGS_2(sdiv64, TCG_CALL_NO_RWG_SE, s64, s64, s64)

DEF_HELPER_FLAGS_1(rbit64, TCG_CALL_NO_RWG_SE, i64, i64)

DEF_HELPER_3(vfp_cmph_a64, i64, f16, f16, ptr)

DEF_HELPER_3(vfp_cmpeh_a64, i64, f16, f16, ptr)

DEF_HELPER_3(vfp_cmps_a64, i64, f32, f32, ptr)

DEF_HELPER_3(vfp_cmpes_a64, i64, f32, f32, ptr)

DEF_HELPER_3(vfp_cmpd_a64, i64, f64, f64, ptr)

target/arm/translate-a64.c

+71 −17
Original line number Diff line number Diff line
@@ -4712,14 +4712,14 @@ static void disas_data_proc_reg(DisasContext *s, uint32_t insn) 
    }

}



static void handle_fp_compare(DisasContext *s, bool is_double,

static void handle_fp_compare(DisasContext *s, int size,

                              unsigned int rn, unsigned int rm,

                              bool cmp_with_zero, bool signal_all_nans)

{

    TCGv_i64 tcg_flags = tcg_temp_new_i64();

    TCGv_ptr fpst = get_fpstatus_ptr(false);

    TCGv_ptr fpst = get_fpstatus_ptr(size == MO_16);



    if (is_double) {

    if (size == MO_64) {

        TCGv_i64 tcg_vn, tcg_vm;



        tcg_vn = read_fp_dreg(s, rn);
@@ -4736,19 +4736,35 @@ static void handle_fp_compare(DisasContext *s, bool is_double, 
        tcg_temp_free_i64(tcg_vn);

        tcg_temp_free_i64(tcg_vm);

    } else {

        TCGv_i32 tcg_vn, tcg_vm;

        TCGv_i32 tcg_vn = tcg_temp_new_i32();

        TCGv_i32 tcg_vm = tcg_temp_new_i32();



        tcg_vn = read_fp_sreg(s, rn);

        read_vec_element_i32(s, tcg_vn, rn, 0, size);

        if (cmp_with_zero) {

            tcg_vm = tcg_const_i32(0);

            tcg_gen_movi_i32(tcg_vm, 0);

        } else {

            tcg_vm = read_fp_sreg(s, rm);

            read_vec_element_i32(s, tcg_vm, rm, 0, size);

        }



        switch (size) {

        case MO_32:

            if (signal_all_nans) {

                gen_helper_vfp_cmpes_a64(tcg_flags, tcg_vn, tcg_vm, fpst);

            } else {

                gen_helper_vfp_cmps_a64(tcg_flags, tcg_vn, tcg_vm, fpst);

            }

            break;

        case MO_16:

            if (signal_all_nans) {

                gen_helper_vfp_cmpeh_a64(tcg_flags, tcg_vn, tcg_vm, fpst);

            } else {

                gen_helper_vfp_cmph_a64(tcg_flags, tcg_vn, tcg_vm, fpst);

            }

            break;

        default:

            g_assert_not_reached();

        }



        tcg_temp_free_i32(tcg_vn);

        tcg_temp_free_i32(tcg_vm);

    }
@@ -4769,16 +4785,35 @@ static void handle_fp_compare(DisasContext *s, bool is_double, 
static void disas_fp_compare(DisasContext *s, uint32_t insn)

{

    unsigned int mos, type, rm, op, rn, opc, op2r;

    int size;



    mos = extract32(insn, 29, 3);

    type = extract32(insn, 22, 2); /* 0 = single, 1 = double */

    type = extract32(insn, 22, 2);

    rm = extract32(insn, 16, 5);

    op = extract32(insn, 14, 2);

    rn = extract32(insn, 5, 5);

    opc = extract32(insn, 3, 2);

    op2r = extract32(insn, 0, 3);



    if (mos || op || op2r || type > 1) {

    if (mos || op || op2r) {

        unallocated_encoding(s);

        return;

    }



    switch (type) {

    case 0:

        size = MO_32;

        break;

    case 1:

        size = MO_64;

        break;

    case 3:

        size = MO_16;

        if (arm_dc_feature(s, ARM_FEATURE_V8_FP16)) {

            break;

        }

        /* fallthru */

    default:

        unallocated_encoding(s);

        return;

    }
@@ -4787,7 +4822,7 @@ static void disas_fp_compare(DisasContext *s, uint32_t insn) 
        return;

    }



    handle_fp_compare(s, type, rn, rm, opc & 1, opc & 2);

    handle_fp_compare(s, size, rn, rm, opc & 1, opc & 2);

}



/* Floating point conditional compare
@@ -4801,16 +4836,35 @@ static void disas_fp_ccomp(DisasContext *s, uint32_t insn) 
    unsigned int mos, type, rm, cond, rn, op, nzcv;

    TCGv_i64 tcg_flags;

    TCGLabel *label_continue = NULL;

    int size;



    mos = extract32(insn, 29, 3);

    type = extract32(insn, 22, 2); /* 0 = single, 1 = double */

    type = extract32(insn, 22, 2);

    rm = extract32(insn, 16, 5);

    cond = extract32(insn, 12, 4);

    rn = extract32(insn, 5, 5);

    op = extract32(insn, 4, 1);

    nzcv = extract32(insn, 0, 4);



    if (mos || type > 1) {

    if (mos) {

        unallocated_encoding(s);

        return;

    }



    switch (type) {

    case 0:

        size = MO_32;

        break;

    case 1:

        size = MO_64;

        break;

    case 3:

        size = MO_16;

        if (arm_dc_feature(s, ARM_FEATURE_V8_FP16)) {

            break;

        }

        /* fallthru */

    default:

        unallocated_encoding(s);

        return;

    }
@@ -4831,7 +4885,7 @@ static void disas_fp_ccomp(DisasContext *s, uint32_t insn) 
        gen_set_label(label_match);

    }



    handle_fp_compare(s, type, rn, rm, false, op);

    handle_fp_compare(s, size, rn, rm, false, op);



    if (cond < 0x0e) {

        gen_set_label(label_continue);