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cortex-m7: fpu: Implement VMAXNM and VMINNM instructions #16

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cortex-m7: fpu: Implement VMAXNM and VMINNM instructions #16

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2 changes: 2 additions & 0 deletions arch/arm/helper.c
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Original file line number Diff line number Diff line change
Expand Up @@ -2364,6 +2364,8 @@ VFP_BINOP(add)
VFP_BINOP(sub)
VFP_BINOP(mul)
VFP_BINOP(div)
VFP_BINOP(minnum)
VFP_BINOP(maxnum)
#undef VFP_BINOP

float32 VFP_HELPER(neg, s)(float32 a)
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4 changes: 4 additions & 0 deletions arch/arm/helper.h
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Expand Up @@ -89,6 +89,10 @@ DEF_HELPER_3(vfp_muls, f32, f32, f32, ptr)
DEF_HELPER_3(vfp_muld, f64, f64, f64, ptr)
DEF_HELPER_3(vfp_divs, f32, f32, f32, ptr)
DEF_HELPER_3(vfp_divd, f64, f64, f64, ptr)
DEF_HELPER_3(vfp_maxnums, f32, f32, f32, ptr)
DEF_HELPER_3(vfp_maxnumd, f64, f64, f64, ptr)
DEF_HELPER_3(vfp_minnums, f32, f32, f32, ptr)
DEF_HELPER_3(vfp_minnumd, f64, f64, f64, ptr)
DEF_HELPER_1(vfp_negs, f32, f32)
DEF_HELPER_1(vfp_negd, f64, f64)
DEF_HELPER_1(vfp_abss, f32, f32)
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58 changes: 58 additions & 0 deletions arch/arm/translate.c
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Expand Up @@ -2789,6 +2789,55 @@ static int generate_vsel_insn(CPUState *env, DisasContext *s, uint32_t insn)
return 0;
}

/* See ARMv7-M Architecture Reference Manual - A7.7.237 */
static int handle_vminmaxnm(uint32_t insn, uint32_t rd, uint32_t rn,
uint32_t rm, uint32_t dp)
{
uint32_t vmin = extract32(insn, 6, 1);
TCGv_ptr fpst = get_fpstatus_ptr(0);

if (dp) {
TCGv_i64 frn, frm, dest;

frn = tcg_temp_new_i64();
frm = tcg_temp_new_i64();
dest = tcg_temp_new_i64();

tcg_gen_ld_f64(frn, cpu_env, vfp_reg_offset(dp, rn));
tcg_gen_ld_f64(frm, cpu_env, vfp_reg_offset(dp, rm));
if (vmin) {
gen_helper_vfp_minnumd(dest, frn, frm, fpst);
} else {
gen_helper_vfp_maxnumd(dest, frn, frm, fpst);
}
tcg_gen_st_f64(dest, cpu_env, vfp_reg_offset(dp, rd));
tcg_temp_free_i64(frn);
tcg_temp_free_i64(frm);
tcg_temp_free_i64(dest);
} else {
TCGv_i32 frn, frm, dest;

frn = tcg_temp_new_i32();
frm = tcg_temp_new_i32();
dest = tcg_temp_new_i32();

tcg_gen_ld_f32(frn, cpu_env, vfp_reg_offset(dp, rn));
tcg_gen_ld_f32(frm, cpu_env, vfp_reg_offset(dp, rm));
if (vmin) {
gen_helper_vfp_minnums(dest, frn, frm, fpst);
} else {
gen_helper_vfp_maxnums(dest, frn, frm, fpst);
}
tcg_gen_st_f32(dest, cpu_env, vfp_reg_offset(dp, rd));
tcg_temp_free_i32(frn);
tcg_temp_free_i32(frm);
tcg_temp_free_i32(dest);
}

tcg_temp_free_ptr(fpst);
return 0;
}

/* Disassemble a VFP instruction. Returns nonzero if an error occurred
(ie. an undefined instruction). */
static int disas_vfp_insn(CPUState *env, DisasContext *s, uint32_t insn)
Expand Down Expand Up @@ -3212,6 +3261,15 @@ static int disas_vfp_insn(CPUState *env, DisasContext *s, uint32_t insn)
case 8: /* div: fn / fm */
gen_vfp_div(dp);
break;
case 9: /* VMAXNM/VMINNM */
/* TODO: may need to introduce feature like VFP5 here */
/* FPv5 FPU add new floating-point maximum and minimum numbers instructions
* See ARMv7-M Architecture Reference Manual - A2.5 */
if (!arm_feature(env, ARM_FEATURE_VFP4)) {
return 1;
}
handle_vminmaxnm(insn, rd, rn, rm, dp);
break;
case 10: /* VFNMA : fd = muladd(-fd, fn, fm) */
case 11: /* VFNMS : fd = muladd(-fd, -fn, fm) */
case 12: /* VFMA : fd = muladd( fd, fn, fm) */
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