These instructions will not be generated by idef-parser, so we override
them manually.
Test cases added to tests/tcg/hexagon/usr.c
Co-authored-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
---
target/hexagon/gen_tcg.h | 10 +++-
target/hexagon/genptr.c | 104 +++++++++++++++++++++++++++++++++++++++
tests/tcg/hexagon/usr.c | 30 ++++++++---
3 files changed, 137 insertions(+), 7 deletions(-)
diff --git a/target/hexagon/gen_tcg.h b/target/hexagon/gen_tcg.h
index 50634ac459..b5fe22a07a 100644
--- a/target/hexagon/gen_tcg.h
+++ b/target/hexagon/gen_tcg.h
@@ -1,5 +1,5 @@
/*
- * Copyright(c) 2019-2021 Qualcomm Innovation Center, Inc. All Rights Reserved.
+ * Copyright(c) 2019-2022 Qualcomm Innovation Center, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -612,6 +612,14 @@
tcg_temp_free(tmp); \
} while (0)
+/* r0 = asr(r1, r2):sat */
+#define fGEN_TCG_S2_asr_r_r_sat(SHORTCODE) \
+ gen_asr_r_r_sat(RdV, RsV, RtV)
+
+/* r0 = asl(r1, r2):sat */
+#define fGEN_TCG_S2_asl_r_r_sat(SHORTCODE) \
+ gen_asl_r_r_sat(RdV, RsV, RtV)
+
/* Floating point */
#define fGEN_TCG_F2_conv_sf2df(SHORTCODE) \
gen_helper_conv_sf2df(RddV, cpu_env, RsV)
diff --git a/target/hexagon/genptr.c b/target/hexagon/genptr.c
index 85416dd530..ccfed9d643 100644
--- a/target/hexagon/genptr.c
+++ b/target/hexagon/genptr.c
@@ -456,6 +456,110 @@ static TCGv gen_8bitsof(TCGv result, TCGv value)
return result;
}
+/* Shift left with saturation */
+static void gen_shl_sat(TCGv dst, TCGv src, TCGv shift_amt)
+{
+ TCGv_i64 src64 = tcg_temp_local_new_i64();
+ TCGv_i64 shift64 = tcg_temp_new_i64();
+ TCGv_i64 dst64 = tcg_temp_new_i64();
+ TCGv dst_sar = tcg_temp_new();
+ TCGv ovf = tcg_temp_new();
+ TCGv satval = tcg_temp_new();
+ TCGv min = tcg_constant_tl(0x80000000);
+ TCGv max = tcg_constant_tl(0x7fffffff);
+
+ /*
+ * dst64 = (int64_t)src << (int64_t)shift_amt
+ * dst = (int32_t)dst64
+ * dst_sar = dst >> shift_amt
+ * if (dst_sar != src) {
+ * usr.OVF = 1
+ * dst = src < 0 ? min : max
+ * }
+ */
+ tcg_gen_ext_i32_i64(src64, src);
+ tcg_gen_ext_i32_i64(shift64, shift_amt);
+ tcg_gen_shl_i64(dst64, src64, shift64);
+
+ tcg_gen_extrl_i64_i32(dst, dst64);
+ tcg_gen_sar_tl(dst_sar, dst, shift_amt);
+
+ tcg_gen_setcond_tl(TCG_COND_NE, ovf, dst_sar, src);
+ tcg_gen_shli_tl(ovf, ovf, reg_field_info[USR_OVF].offset);
+ tcg_gen_or_tl(hex_new_value[HEX_REG_USR], hex_new_value[HEX_REG_USR], ovf);
+
+ tcg_gen_movcond_tl(TCG_COND_LT, satval, src, tcg_constant_tl(0),
+ min, max);
+ tcg_gen_movcond_tl(TCG_COND_EQ, dst, dst_sar, src, dst, satval);
+
+ tcg_temp_free_i64(src64);
+ tcg_temp_free_i64(shift64);
+ tcg_temp_free_i64(dst64);
+ tcg_temp_free(dst_sar);
+ tcg_temp_free(ovf);
+ tcg_temp_free(satval);
+}
+
+static void gen_sar(TCGv dst, TCGv src, TCGv shift_amt)
+{
+ /*
+ * Shift arithmetic right
+ * Robust when shift_amt is >31 bits
+ */
+ TCGv tmp = tcg_temp_new();
+ tcg_gen_umin_tl(tmp, shift_amt, tcg_constant_tl(31));
+ tcg_gen_sar_tl(dst, src, tmp);
+ tcg_temp_free(tmp);
+}
+
+/* Bidirectional shift right with saturation */
+static void gen_asr_r_r_sat(TCGv RdV, TCGv RsV, TCGv RtV)
+{
+ TCGv shift_amt = tcg_temp_local_new();
+ TCGLabel *positive = gen_new_label();
+ TCGLabel *done = gen_new_label();
+
+ tcg_gen_sextract_i32(shift_amt, RtV, 0, 7);
+ tcg_gen_brcondi_tl(TCG_COND_GE, shift_amt, 0, positive);
+
+ /* Negative shift amount => shift left */
+ tcg_gen_neg_tl(shift_amt, shift_amt);
+ gen_shl_sat(RdV, RsV, shift_amt);
+ tcg_gen_br(done);
+
+ gen_set_label(positive);
+ /* Positive shift amount => shift right */
+ gen_sar(RdV, RsV, shift_amt);
+
+ gen_set_label(done);
+
+ tcg_temp_free(shift_amt);
+}
+
+/* Bidirectional shift left with saturation */
+static void gen_asl_r_r_sat(TCGv RdV, TCGv RsV, TCGv RtV)
+{
+ TCGv shift_amt = tcg_temp_local_new();
+ TCGLabel *positive = gen_new_label();
+ TCGLabel *done = gen_new_label();
+
+ tcg_gen_sextract_i32(shift_amt, RtV, 0, 7);
+ tcg_gen_brcondi_tl(TCG_COND_GE, shift_amt, 0, positive);
+
+ /* Negative shift amount => shift right */
+ tcg_gen_neg_tl(shift_amt, shift_amt);
+ gen_sar(RdV, RsV, shift_amt);
+ tcg_gen_br(done);
+
+ gen_set_label(positive);
+ /* Positive shift amount => shift left */
+ gen_shl_sat(RdV, RsV, shift_amt);
+
+ gen_set_label(done);
+
+ tcg_temp_free(shift_amt);
+}
+
static intptr_t vreg_src_off(DisasContext *ctx, int num)
{
intptr_t offset = offsetof(CPUHexagonState, VRegs[num]);
diff --git a/tests/tcg/hexagon/usr.c b/tests/tcg/hexagon/usr.c
index fb4514989c..63c7d2700f 100644
--- a/tests/tcg/hexagon/usr.c
+++ b/tests/tcg/hexagon/usr.c
@@ -429,6 +429,7 @@ FUNC_P_OP_P(vabshsat, "%0 = vabsh(%2):sat")
FUNC_P_OP_PP(vnavgwr, "%0 = vnavgw(%2, %3):rnd:sat")
FUNC_R_OP_RI(round_ri_sat, "%0 = round(%2, #%3):sat")
FUNC_R_OP_RR(asr_r_r_sat, "%0 = asr(%2, %3):sat")
+FUNC_R_OP_RR(asl_r_r_sat, "%0 = asl(%2, %3):sat")
FUNC_XPp_OP_PP(ACS, "%0, p2 = vacsh(%3, %4)")
@@ -907,12 +908,29 @@ int main()
TEST_R_OP_RI(round_ri_sat, 0x0000ffff, 2, 0x00004000, USR_CLEAR);
TEST_R_OP_RI(round_ri_sat, 0x7fffffff, 2, 0x1fffffff, USR_OVF);
- TEST_R_OP_RR(asr_r_r_sat, 0x0000ffff, 0x00000002, 0x00003fff,
- USR_CLEAR);
- TEST_R_OP_RR(asr_r_r_sat, 0x00ffffff, 0xfffffff5, 0x7fffffff,
- USR_OVF);
- TEST_R_OP_RR(asr_r_r_sat, 0x80000000, 0xfffffff5, 0x80000000,
- USR_OVF);
+ TEST_R_OP_RR(asr_r_r_sat, 0x0000ffff, 0x02, 0x00003fff, USR_CLEAR);
+ TEST_R_OP_RR(asr_r_r_sat, 0x80000000, 0x01, 0xc0000000, USR_CLEAR);
+ TEST_R_OP_RR(asr_r_r_sat, 0xffffffff, 0x01, 0xffffffff, USR_CLEAR);
+ TEST_R_OP_RR(asr_r_r_sat, 0x00ffffff, 0xf5, 0x7fffffff, USR_OVF);
+ TEST_R_OP_RR(asr_r_r_sat, 0x80000000, 0xf5, 0x80000000, USR_OVF);
+ TEST_R_OP_RR(asr_r_r_sat, 0x7fff0000, 0x42, 0x7fffffff, USR_OVF);
+ TEST_R_OP_RR(asr_r_r_sat, 0xff000000, 0x42, 0x80000000, USR_OVF);
+ TEST_R_OP_RR(asr_r_r_sat, 4096, 32, 0x00000000, USR_CLEAR);
+ TEST_R_OP_RR(asr_r_r_sat, 4096, -32, 0x7fffffff, USR_OVF);
+ TEST_R_OP_RR(asr_r_r_sat, -4096, 32, 0xffffffff, USR_CLEAR);
+ TEST_R_OP_RR(asr_r_r_sat, -4096, -32, 0x80000000, USR_OVF);
+
+ TEST_R_OP_RR(asl_r_r_sat, 0x00000000, 0x40, 0x00000000, USR_CLEAR);
+ TEST_R_OP_RR(asl_r_r_sat, 0x80000000, 0xff, 0xc0000000, USR_CLEAR);
+ TEST_R_OP_RR(asl_r_r_sat, 0xffffffff, 0xff, 0xffffffff, USR_CLEAR);
+ TEST_R_OP_RR(asl_r_r_sat, 0x00ffffff, 0x0b, 0x7fffffff, USR_OVF);
+ TEST_R_OP_RR(asl_r_r_sat, 0x80000000, 0x0b, 0x80000000, USR_OVF);
+ TEST_R_OP_RR(asl_r_r_sat, 0x7fff0000, 0xbe, 0x7fffffff, USR_OVF);
+ TEST_R_OP_RR(asl_r_r_sat, 0xff000000, 0xbe, 0x80000000, USR_OVF);
+ TEST_R_OP_RR(asl_r_r_sat, 4096, 32, 0x7fffffff, USR_OVF);
+ TEST_R_OP_RR(asl_r_r_sat, 4096, -32, 0x00000000, USR_CLEAR);
+ TEST_R_OP_RR(asl_r_r_sat, -4096, 32, 0x80000000, USR_OVF);
+ TEST_R_OP_RR(asl_r_r_sat, -4096, -32, 0xffffffff, USR_CLEAR);
TEST_XPp_OP_PP(ACS, 0x0004000300020001ULL, 0x0001000200030004ULL,
0x0000000000000000ULL, 0x0004000300030004ULL, 0xf0,
--
2.17.1
On 11/8/22 15:05, Taylor Simpson wrote:
> +/* Shift left with saturation */
> +static void gen_shl_sat(TCGv dst, TCGv src, TCGv shift_amt)
> +{
> + TCGv_i64 src64 = tcg_temp_local_new_i64();
> + TCGv_i64 shift64 = tcg_temp_new_i64();
> + TCGv_i64 dst64 = tcg_temp_new_i64();
> + TCGv dst_sar = tcg_temp_new();
> + TCGv ovf = tcg_temp_new();
> + TCGv satval = tcg_temp_new();
> + TCGv min = tcg_constant_tl(0x80000000);
> + TCGv max = tcg_constant_tl(0x7fffffff);
> +
> + /*
> + * dst64 = (int64_t)src << (int64_t)shift_amt
> + * dst = (int32_t)dst64
> + * dst_sar = dst >> shift_amt
> + * if (dst_sar != src) {
> + * usr.OVF = 1
> + * dst = src < 0 ? min : max
> + * }
> + */
> + tcg_gen_ext_i32_i64(src64, src);
> + tcg_gen_ext_i32_i64(shift64, shift_amt);
> + tcg_gen_shl_i64(dst64, src64, shift64);
> +
> + tcg_gen_extrl_i64_i32(dst, dst64);
> + tcg_gen_sar_tl(dst_sar, dst, shift_amt);
I don't think this is quite right. In particular:
> +static void gen_asr_r_r_sat(TCGv RdV, TCGv RsV, TCGv RtV)
> +{
> + TCGv shift_amt = tcg_temp_local_new();
> + TCGLabel *positive = gen_new_label();
> + TCGLabel *done = gen_new_label();
> +
> + tcg_gen_sextract_i32(shift_amt, RtV, 0, 7);
This suggests shift amounts -64 ... 63.
> + tcg_gen_brcondi_tl(TCG_COND_GE, shift_amt, 0, positive);
> +
> + /* Negative shift amount => shift left */
> + tcg_gen_neg_tl(shift_amt, shift_amt);
-64 -> 64.
So! We have two out-of-range shifts in gen_shl_sat, both i64 and i32.
If we fix one, then we don't even need the extension to i64 either.
Consider
/*
* sh32 = shift & 31;
* dst = sh32 == shift ? src : 0;
* dst <<= sh32;
* dst_sar = dst >> sh32;
* if (dst_sar != src) ...
*/
tcg_gen_andi_i32(sh32, shift_amt, 31);
tcg_gen_movcond_i32(TCG_COND_EQ, dst,
sh32, shift_amt,
src, tcg_constant_i32(0));
tcg_gen_shl_i32(dst, dst, sh32);
tcg_gen_sar_i32(dst_sar, dst, sh32);
r~
> -----Original Message----- > From: Richard Henderson <richard.henderson@linaro.org> > Sent: Tuesday, November 8, 2022 1:20 AM > To: Taylor Simpson <tsimpson@quicinc.com>; qemu-devel@nongnu.org > Cc: philmd@linaro.org; ale@rev.ng; anjo@rev.ng; Brian Cain > <bcain@quicinc.com>; Matheus Bernardino (QUIC) > <quic_mathbern@quicinc.com> > Subject: Re: [PATCH v4 03/11] Hexagon (target/hexagon) Add overrides for > S2_asr_r_r_sat/S2_asl_r_r_sat > > Consider > > /* > * sh32 = shift & 31; > * dst = sh32 == shift ? src : 0; > * dst <<= sh32; > * dst_sar = dst >> sh32; > * if (dst_sar != src) ... > */ > tcg_gen_andi_i32(sh32, shift_amt, 31); > tcg_gen_movcond_i32(TCG_COND_EQ, dst, > sh32, shift_amt, > src, tcg_constant_i32(0)); > tcg_gen_shl_i32(dst, dst, sh32); > tcg_gen_sar_i32(dst_sar, dst, sh32); Will do. Thanks, Taylor
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