From: Taylor Simpson <tsimp...@quicinc.com> Rd32,Pe4 = sfinvsqrta(Rs32) Square root approx
The helper packs the 2 32-bit results into a 64-bit value, and the fGEN_TCG override unpacks them into the proper results. Test cases in tests/tcg/hexagon/multi_result.c FP exception tests added to tests/tcg/hexagon/fpstuff.c Signed-off-by: Taylor Simpson <tsimp...@quicinc.com> Reviewed-by: Richard Henderson <richard.hender...@linaro.org> Message-Id: <1617930474-31979-19-git-send-email-tsimp...@quicinc.com> Signed-off-by: Richard Henderson <richard.hender...@linaro.org> --- target/hexagon/arch.h | 2 ++ target/hexagon/gen_tcg.h | 16 +++++++++++++++ target/hexagon/helper.h | 1 + target/hexagon/arch.c | 21 ++++++++++++++++++- target/hexagon/op_helper.c | 21 +++++++++++++++++++ tests/tcg/hexagon/fpstuff.c | 15 ++++++++++++++ tests/tcg/hexagon/multi_result.c | 29 +++++++++++++++++++++++++++ target/hexagon/imported/encode_pp.def | 1 + target/hexagon/imported/float.idef | 16 +++++++++++++++ 9 files changed, 121 insertions(+), 1 deletion(-) diff --git a/target/hexagon/arch.h b/target/hexagon/arch.h index b6634e9615..3e0c334209 100644 --- a/target/hexagon/arch.h +++ b/target/hexagon/arch.h @@ -32,4 +32,6 @@ int arch_sf_invsqrt_common(float32 *Rs, float32 *Rd, int *adjust, extern const uint8_t recip_lookup_table[128]; +extern const uint8_t invsqrt_lookup_table[128]; + #endif diff --git a/target/hexagon/gen_tcg.h b/target/hexagon/gen_tcg.h index 428a670281..d78e7b8e5c 100644 --- a/target/hexagon/gen_tcg.h +++ b/target/hexagon/gen_tcg.h @@ -216,6 +216,22 @@ tcg_temp_free_i64(tmp); \ } while (0) +/* + * Approximation of the reciprocal square root + * r1,p0 = sfinvsqrta(r0) + * + * The helper packs the 2 32-bit results into a 64-bit value, + * so unpack them into the proper results. + */ +#define fGEN_TCG_F2_sfinvsqrta(SHORTCODE) \ + do { \ + TCGv_i64 tmp = tcg_temp_new_i64(); \ + gen_helper_sfinvsqrta(tmp, cpu_env, RsV); \ + tcg_gen_extrh_i64_i32(RdV, tmp); \ + tcg_gen_extrl_i64_i32(PeV, tmp); \ + tcg_temp_free_i64(tmp); \ + } while (0) + /* Floating point */ #define fGEN_TCG_F2_conv_sf2df(SHORTCODE) \ gen_helper_conv_sf2df(RddV, cpu_env, RsV) diff --git a/target/hexagon/helper.h b/target/hexagon/helper.h index b377293dd3..cb7508f746 100644 --- a/target/hexagon/helper.h +++ b/target/hexagon/helper.h @@ -25,6 +25,7 @@ DEF_HELPER_FLAGS_3(debug_commit_end, TCG_CALL_NO_WG, void, env, int, int) DEF_HELPER_2(commit_store, void, env, int) DEF_HELPER_FLAGS_4(fcircadd, TCG_CALL_NO_RWG_SE, s32, s32, s32, s32, s32) DEF_HELPER_3(sfrecipa, i64, env, f32, f32) +DEF_HELPER_2(sfinvsqrta, i64, env, f32) /* Floating point */ DEF_HELPER_2(conv_sf2df, f64, env, f32) diff --git a/target/hexagon/arch.c b/target/hexagon/arch.c index 46edf45b13..dee852e106 100644 --- a/target/hexagon/arch.c +++ b/target/hexagon/arch.c @@ -247,7 +247,7 @@ int arch_sf_invsqrt_common(float32 *Rs, float32 *Rd, int *adjust, int r_exp; int ret = 0; RsV = *Rs; - if (float32_is_infinity(RsV)) { + if (float32_is_any_nan(RsV)) { if (extract32(RsV, 22, 1) == 0) { float_raise(float_flag_invalid, fp_status); } @@ -299,3 +299,22 @@ const uint8_t recip_lookup_table[128] = { 0x011, 0x00f, 0x00e, 0x00d, 0x00c, 0x00b, 0x00a, 0x009, 0x008, 0x007, 0x006, 0x005, 0x004, 0x003, 0x002, 0x000, }; + +const uint8_t invsqrt_lookup_table[128] = { + 0x069, 0x066, 0x063, 0x061, 0x05e, 0x05b, 0x059, 0x057, + 0x054, 0x052, 0x050, 0x04d, 0x04b, 0x049, 0x047, 0x045, + 0x043, 0x041, 0x03f, 0x03d, 0x03b, 0x039, 0x037, 0x036, + 0x034, 0x032, 0x030, 0x02f, 0x02d, 0x02c, 0x02a, 0x028, + 0x027, 0x025, 0x024, 0x022, 0x021, 0x01f, 0x01e, 0x01d, + 0x01b, 0x01a, 0x019, 0x017, 0x016, 0x015, 0x014, 0x012, + 0x011, 0x010, 0x00f, 0x00d, 0x00c, 0x00b, 0x00a, 0x009, + 0x008, 0x007, 0x006, 0x005, 0x004, 0x003, 0x002, 0x001, + 0x0fe, 0x0fa, 0x0f6, 0x0f3, 0x0ef, 0x0eb, 0x0e8, 0x0e4, + 0x0e1, 0x0de, 0x0db, 0x0d7, 0x0d4, 0x0d1, 0x0ce, 0x0cb, + 0x0c9, 0x0c6, 0x0c3, 0x0c0, 0x0be, 0x0bb, 0x0b8, 0x0b6, + 0x0b3, 0x0b1, 0x0af, 0x0ac, 0x0aa, 0x0a8, 0x0a5, 0x0a3, + 0x0a1, 0x09f, 0x09d, 0x09b, 0x099, 0x097, 0x095, 0x093, + 0x091, 0x08f, 0x08d, 0x08b, 0x089, 0x087, 0x086, 0x084, + 0x082, 0x080, 0x07f, 0x07d, 0x07b, 0x07a, 0x078, 0x077, + 0x075, 0x074, 0x072, 0x071, 0x06f, 0x06e, 0x06c, 0x06b, +}; diff --git a/target/hexagon/op_helper.c b/target/hexagon/op_helper.c index 75861e26c4..a25fb98f24 100644 --- a/target/hexagon/op_helper.c +++ b/target/hexagon/op_helper.c @@ -326,6 +326,27 @@ uint64_t HELPER(sfrecipa)(CPUHexagonState *env, float32 RsV, float32 RtV) return ((uint64_t)RdV << 32) | PeV; } +uint64_t HELPER(sfinvsqrta)(CPUHexagonState *env, float32 RsV) +{ + int PeV = 0; + float32 RdV; + int idx; + int adjust; + int mant; + int exp; + + arch_fpop_start(env); + if (arch_sf_invsqrt_common(&RsV, &RdV, &adjust, &env->fp_status)) { + PeV = adjust; + idx = (RsV >> 17) & 0x7f; + mant = (invsqrt_lookup_table[idx] << 15); + exp = SF_BIAS - ((float32_getexp(RsV) - SF_BIAS) >> 1) - 1; + RdV = build_float32(extract32(RsV, 31, 1), exp, mant); + } + arch_fpop_end(env); + return ((uint64_t)RdV << 32) | PeV; +} + /* * mem_noshuf * Section 5.5 of the Hexagon V67 Programmer's Reference Manual diff --git a/tests/tcg/hexagon/fpstuff.c b/tests/tcg/hexagon/fpstuff.c index 8e3ba780d2..0dff429f4c 100644 --- a/tests/tcg/hexagon/fpstuff.c +++ b/tests/tcg/hexagon/fpstuff.c @@ -441,6 +441,20 @@ static void check_canonical_NaN(void) check_fpstatus(usr, 0); } +static void check_invsqrta(void) +{ + int result; + int predval; + + asm volatile("%0,p0 = sfinvsqrta(%2)\n\t" + "%1 = p0\n\t" + : "+r"(result), "=r"(predval) + : "r"(0x7f800000) + : "p0"); + check32(result, 0xff800000); + check32(predval, 0x0); +} + static void check_float2int_convs() { int res32; @@ -590,6 +604,7 @@ int main() check_dfminmax(); check_recip_exception(); check_canonical_NaN(); + check_invsqrta(); check_float2int_convs(); puts(err ? "FAIL" : "PASS"); diff --git a/tests/tcg/hexagon/multi_result.c b/tests/tcg/hexagon/multi_result.c index cb7dd313d4..67aa46249b 100644 --- a/tests/tcg/hexagon/multi_result.c +++ b/tests/tcg/hexagon/multi_result.c @@ -31,6 +31,20 @@ static int sfrecipa(int Rs, int Rt, int *pred_result) return result; } +static int sfinvsqrta(int Rs, int *pred_result) +{ + int result; + int predval; + + asm volatile("%0,p0 = sfinvsqrta(%2)\n\t" + "%1 = p0\n\t" + : "+r"(result), "=r"(predval) + : "r"(Rs) + : "p0"); + *pred_result = predval; + return result; +} + int err; static void check(int val, int expect) @@ -59,9 +73,24 @@ static void test_sfrecipa() check_p(pred_result, 0x00); } +static void test_sfinvsqrta() +{ + int res; + int pred_result; + + res = sfinvsqrta(0x04030201, &pred_result); + check(res, 0x4d330000); + check_p(pred_result, 0xe0); + + res = sfinvsqrta(0x0, &pred_result); + check(res, 0x3f800000); + check_p(pred_result, 0x0); +} + int main() { test_sfrecipa(); + test_sfinvsqrta(); puts(err ? "FAIL" : "PASS"); return err; diff --git a/target/hexagon/imported/encode_pp.def b/target/hexagon/imported/encode_pp.def index b01b4d7aa7..18fe45d696 100644 --- a/target/hexagon/imported/encode_pp.def +++ b/target/hexagon/imported/encode_pp.def @@ -1642,6 +1642,7 @@ SH2_RR_ENC(F2_conv_sf2w, "1011","100","-","000","ddddd") SH2_RR_ENC(F2_conv_sf2uw_chop, "1011","011","-","001","ddddd") SH2_RR_ENC(F2_conv_sf2w_chop, "1011","100","-","001","ddddd") SH2_RR_ENC(F2_sffixupr, "1011","101","-","000","ddddd") +SH2_RR_ENC(F2_sfinvsqrta, "1011","111","-","0ee","ddddd") DEF_FIELDROW_DESC32(ICLASS_S2op" 1100 -------- PP------ --------","[#12] Rd=(Rs,#u6)") diff --git a/target/hexagon/imported/float.idef b/target/hexagon/imported/float.idef index eb5415801a..3e75bc4604 100644 --- a/target/hexagon/imported/float.idef +++ b/target/hexagon/imported/float.idef @@ -178,6 +178,22 @@ Q6INSN(F2_sffixupd,"Rd32=sffixupd(Rs32,Rt32)",ATTRIBS(), RdV = RtV; }) +Q6INSN(F2_sfinvsqrta,"Rd32,Pe4=sfinvsqrta(Rs32)",ATTRIBS(), +"Reciprocal Square Root Approximation", +{ + fHIDE(int idx;) + fHIDE(int adjust;) + fHIDE(int mant;) + fHIDE(int exp;) + if (fSF_INVSQRT_COMMON(RsV,RdV,adjust)) { + PeV = adjust; + idx = (RsV >> 17) & 0x7f; + mant = (fSF_INVSQRT_LOOKUP(idx) << 15); + exp = fSF_BIAS() - ((fSF_GETEXP(RsV) - fSF_BIAS()) >> 1) - 1; + RdV = fMAKESF(fGETBIT(31,RsV),exp,mant); + } +}) + Q6INSN(F2_sffixupr,"Rd32=sffixupr(Rs32)",ATTRIBS(), "Fix Up Radicand", { -- 2.25.1