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[Qemu-devel] [PATCH v2 06/14] target/arm: Implement FCVT (scalar, intege
From: |
Richard Henderson |
Subject: |
[Qemu-devel] [PATCH v2 06/14] target/arm: Implement FCVT (scalar, integer) for fp16 |
Date: |
Wed, 2 May 2018 15:15:44 -0700 |
Cc: address@hidden
Reviewed-by: Alex Bennée <address@hidden>
Signed-off-by: Richard Henderson <address@hidden>
---
target/arm/helper.h | 6 +++
target/arm/helper.c | 38 +++++++++++++++++-
target/arm/translate-a64.c | 96 ++++++++++++++++++++++++++++++++++++++--------
3 files changed, 122 insertions(+), 18 deletions(-)
diff --git a/target/arm/helper.h b/target/arm/helper.h
index 1969b37f2d..ce89968b2d 100644
--- a/target/arm/helper.h
+++ b/target/arm/helper.h
@@ -151,6 +151,10 @@ DEF_HELPER_3(vfp_touhd_round_to_zero, i64, f64, i32, ptr)
DEF_HELPER_3(vfp_tould_round_to_zero, i64, f64, i32, ptr)
DEF_HELPER_3(vfp_touhh, i32, f16, i32, ptr)
DEF_HELPER_3(vfp_toshh, i32, f16, i32, ptr)
+DEF_HELPER_3(vfp_toulh, i32, f16, i32, ptr)
+DEF_HELPER_3(vfp_toslh, i32, f16, i32, ptr)
+DEF_HELPER_3(vfp_touqh, i64, f16, i32, ptr)
+DEF_HELPER_3(vfp_tosqh, i64, f16, i32, ptr)
DEF_HELPER_3(vfp_toshs, i32, f32, i32, ptr)
DEF_HELPER_3(vfp_tosls, i32, f32, i32, ptr)
DEF_HELPER_3(vfp_tosqs, i64, f32, i32, ptr)
@@ -177,6 +181,8 @@ DEF_HELPER_3(vfp_ultod, f64, i64, i32, ptr)
DEF_HELPER_3(vfp_uqtod, f64, i64, i32, ptr)
DEF_HELPER_3(vfp_sltoh, f16, i32, i32, ptr)
DEF_HELPER_3(vfp_ultoh, f16, i32, i32, ptr)
+DEF_HELPER_3(vfp_sqtoh, f16, i64, i32, ptr)
+DEF_HELPER_3(vfp_uqtoh, f16, i64, i32, ptr)
DEF_HELPER_FLAGS_2(set_rmode, TCG_CALL_NO_RWG, i32, i32, ptr)
DEF_HELPER_FLAGS_2(set_neon_rmode, TCG_CALL_NO_RWG, i32, i32, env)
diff --git a/target/arm/helper.c b/target/arm/helper.c
index ba04cddda0..1fbf5fdec9 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -11427,8 +11427,12 @@ VFP_CONV_FIX_A64(uq, s, 32, 64, uint64)
#undef VFP_CONV_FIX_A64
/* Conversion to/from f16 can overflow to infinity before/after scaling.
- * Therefore we convert to f64 (which does not round), scale,
- * and then convert f64 to f16 (which may round).
+ * Therefore we convert to f64, scale, and then convert f64 to f16; or
+ * vice versa for conversion to integer.
+ *
+ * For 16- and 32-bit integers, the conversion to f64 never rounds.
+ * For 64-bit integers, any integer that would cause rounding will also
+ * overflow to f16 infinity, so there is no double rounding problem.
*/
static float16 do_postscale_fp16(float64 f, int shift, float_status *fpst)
@@ -11446,6 +11450,16 @@ float16 HELPER(vfp_ultoh)(uint32_t x, uint32_t shift,
void *fpst)
return do_postscale_fp16(uint32_to_float64(x, fpst), shift, fpst);
}
+float16 HELPER(vfp_sqtoh)(uint64_t x, uint32_t shift, void *fpst)
+{
+ return do_postscale_fp16(int64_to_float64(x, fpst), shift, fpst);
+}
+
+float16 HELPER(vfp_uqtoh)(uint64_t x, uint32_t shift, void *fpst)
+{
+ return do_postscale_fp16(uint64_to_float64(x, fpst), shift, fpst);
+}
+
static float64 do_prescale_fp16(float16 f, int shift, float_status *fpst)
{
if (unlikely(float16_is_any_nan(f))) {
@@ -11475,6 +11489,26 @@ uint32_t HELPER(vfp_touhh)(float16 x, uint32_t shift,
void *fpst)
return float64_to_uint16(do_prescale_fp16(x, shift, fpst), fpst);
}
+uint32_t HELPER(vfp_toslh)(float16 x, uint32_t shift, void *fpst)
+{
+ return float64_to_int32(do_prescale_fp16(x, shift, fpst), fpst);
+}
+
+uint32_t HELPER(vfp_toulh)(float16 x, uint32_t shift, void *fpst)
+{
+ return float64_to_uint32(do_prescale_fp16(x, shift, fpst), fpst);
+}
+
+uint64_t HELPER(vfp_tosqh)(float16 x, uint32_t shift, void *fpst)
+{
+ return float64_to_int64(do_prescale_fp16(x, shift, fpst), fpst);
+}
+
+uint64_t HELPER(vfp_touqh)(float16 x, uint32_t shift, void *fpst)
+{
+ return float64_to_uint64(do_prescale_fp16(x, shift, fpst), fpst);
+}
+
/* Set the current fp rounding mode and return the old one.
* The argument is a softfloat float_round_ value.
*/
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 247a4f0cce..d794744aec 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -5274,11 +5274,11 @@ static void handle_fpfpcvt(DisasContext *s, int rd, int
rn, int opcode,
bool itof, int rmode, int scale, int sf, int type)
{
bool is_signed = !(opcode & 1);
- bool is_double = type;
TCGv_ptr tcg_fpstatus;
- TCGv_i32 tcg_shift;
+ TCGv_i32 tcg_shift, tcg_single;
+ TCGv_i64 tcg_double;
- tcg_fpstatus = get_fpstatus_ptr(false);
+ tcg_fpstatus = get_fpstatus_ptr(type == 3);
tcg_shift = tcg_const_i32(64 - scale);
@@ -5296,8 +5296,9 @@ static void handle_fpfpcvt(DisasContext *s, int rd, int
rn, int opcode,
tcg_int = tcg_extend;
}
- if (is_double) {
- TCGv_i64 tcg_double = tcg_temp_new_i64();
+ switch (type) {
+ case 1: /* float64 */
+ tcg_double = tcg_temp_new_i64();
if (is_signed) {
gen_helper_vfp_sqtod(tcg_double, tcg_int,
tcg_shift, tcg_fpstatus);
@@ -5307,8 +5308,10 @@ static void handle_fpfpcvt(DisasContext *s, int rd, int
rn, int opcode,
}
write_fp_dreg(s, rd, tcg_double);
tcg_temp_free_i64(tcg_double);
- } else {
- TCGv_i32 tcg_single = tcg_temp_new_i32();
+ break;
+
+ case 0: /* float32 */
+ tcg_single = tcg_temp_new_i32();
if (is_signed) {
gen_helper_vfp_sqtos(tcg_single, tcg_int,
tcg_shift, tcg_fpstatus);
@@ -5318,6 +5321,23 @@ static void handle_fpfpcvt(DisasContext *s, int rd, int
rn, int opcode,
}
write_fp_sreg(s, rd, tcg_single);
tcg_temp_free_i32(tcg_single);
+ break;
+
+ case 3: /* float16 */
+ tcg_single = tcg_temp_new_i32();
+ if (is_signed) {
+ gen_helper_vfp_sqtoh(tcg_single, tcg_int,
+ tcg_shift, tcg_fpstatus);
+ } else {
+ gen_helper_vfp_uqtoh(tcg_single, tcg_int,
+ tcg_shift, tcg_fpstatus);
+ }
+ write_fp_sreg(s, rd, tcg_single);
+ tcg_temp_free_i32(tcg_single);
+ break;
+
+ default:
+ g_assert_not_reached();
}
} else {
TCGv_i64 tcg_int = cpu_reg(s, rd);
@@ -5334,8 +5354,9 @@ static void handle_fpfpcvt(DisasContext *s, int rd, int
rn, int opcode,
gen_helper_set_rmode(tcg_rmode, tcg_rmode, tcg_fpstatus);
- if (is_double) {
- TCGv_i64 tcg_double = read_fp_dreg(s, rn);
+ switch (type) {
+ case 1: /* float64 */
+ tcg_double = read_fp_dreg(s, rn);
if (is_signed) {
if (!sf) {
gen_helper_vfp_tosld(tcg_int, tcg_double,
@@ -5353,9 +5374,14 @@ static void handle_fpfpcvt(DisasContext *s, int rd, int
rn, int opcode,
tcg_shift, tcg_fpstatus);
}
}
+ if (!sf) {
+ tcg_gen_ext32u_i64(tcg_int, tcg_int);
+ }
tcg_temp_free_i64(tcg_double);
- } else {
- TCGv_i32 tcg_single = read_fp_sreg(s, rn);
+ break;
+
+ case 0: /* float32 */
+ tcg_single = read_fp_sreg(s, rn);
if (sf) {
if (is_signed) {
gen_helper_vfp_tosqs(tcg_int, tcg_single,
@@ -5377,14 +5403,39 @@ static void handle_fpfpcvt(DisasContext *s, int rd, int
rn, int opcode,
tcg_temp_free_i32(tcg_dest);
}
tcg_temp_free_i32(tcg_single);
+ break;
+
+ case 3: /* float16 */
+ tcg_single = read_fp_sreg(s, rn);
+ if (sf) {
+ if (is_signed) {
+ gen_helper_vfp_tosqh(tcg_int, tcg_single,
+ tcg_shift, tcg_fpstatus);
+ } else {
+ gen_helper_vfp_touqh(tcg_int, tcg_single,
+ tcg_shift, tcg_fpstatus);
+ }
+ } else {
+ TCGv_i32 tcg_dest = tcg_temp_new_i32();
+ if (is_signed) {
+ gen_helper_vfp_toslh(tcg_dest, tcg_single,
+ tcg_shift, tcg_fpstatus);
+ } else {
+ gen_helper_vfp_toulh(tcg_dest, tcg_single,
+ tcg_shift, tcg_fpstatus);
+ }
+ tcg_gen_extu_i32_i64(tcg_int, tcg_dest);
+ tcg_temp_free_i32(tcg_dest);
+ }
+ tcg_temp_free_i32(tcg_single);
+ break;
+
+ default:
+ g_assert_not_reached();
}
gen_helper_set_rmode(tcg_rmode, tcg_rmode, tcg_fpstatus);
tcg_temp_free_i32(tcg_rmode);
-
- if (!sf) {
- tcg_gen_ext32u_i64(tcg_int, tcg_int);
- }
}
tcg_temp_free_ptr(tcg_fpstatus);
@@ -5553,7 +5604,20 @@ static void disas_fp_int_conv(DisasContext *s, uint32_t
insn)
/* actual FP conversions */
bool itof = extract32(opcode, 1, 1);
- if (type > 1 || (rmode != 0 && opcode > 1)) {
+ if (rmode != 0 && opcode > 1) {
+ unallocated_encoding(s);
+ return;
+ }
+ switch (type) {
+ case 0: /* float32 */
+ case 1: /* float64 */
+ break;
+ case 3: /* float16 */
+ if (arm_dc_feature(s, ARM_FEATURE_V8_FP16)) {
+ break;
+ }
+ /* fallthru */
+ default:
unallocated_encoding(s);
return;
}
--
2.14.3
- [Qemu-devel] [PATCH v2 00/14] target/arm: Fixups for ARM_FEATURE_V8_FP16, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 02/14] target/arm: Implement vector shifted FCVT for fp16, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 01/14] target/arm: Implement vector shifted SCVF/UCVF for fp16, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 03/14] target/arm: Fix float16 to/from int16, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 04/14] target/arm: Clear SVE high bits for FMOV, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 05/14] target/arm: Implement FMOV (general) for fp16, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 06/14] target/arm: Implement FCVT (scalar, integer) for fp16,
Richard Henderson <=
- [Qemu-devel] [PATCH v2 09/14] target/arm: Implement FP data-processing (2 source) for fp16, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 07/14] target/arm: Implement FCVT (scalar, fixed-point) for fp16, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 14/14] target/arm: Fix sqrt_f16 exception raising, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 10/14] target/arm: Implement FP data-processing (3 source) for fp16, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 12/14] target/arm: Implement FCSEL for fp16, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 08/14] target/arm: Introduce and use read_fp_hreg, Richard Henderson, 2018/05/02
- [Qemu-devel] [PATCH v2 11/14] target/arm: Implement FCMP for fp16, Richard Henderson, 2018/05/02