This implements the half-precision variants of the across vector
reduction operations. This involves a re-factor of the reduction code
which more closely matches the ARM ARM order (and handles 8 element
reductions).
As SoftFloat3c doesn't support the operations we need we use the
expanded support from 2a. To keep things neat we put them in another
helper file - advsimd_2a_helper.c.
Signed-off-by: Alex Bennée <alex.ben...@linaro.org>
---
target/arm/Makefile.objs | 2 +-
target/arm/advsimd_2a_helper.c | 34 ++++++++++
target/arm/helper-a64.h | 5 ++
target/arm/translate-a64.c | 147 ++++++++++++++++++++++++++---------------
4 files changed, 133 insertions(+), 55 deletions(-)
create mode 100644 target/arm/advsimd_2a_helper.c
diff --git a/target/arm/Makefile.objs b/target/arm/Makefile.objs
index d4e81b13f0..2f8cf3d93a 100644
--- a/target/arm/Makefile.objs
+++ b/target/arm/Makefile.objs
@@ -6,7 +6,7 @@ obj-$(call land,$(CONFIG_KVM),$(TARGET_AARCH64)) += kvm64.o
obj-$(call lnot,$(CONFIG_KVM)) += kvm-stub.o
obj-y += translate.o op_helper.o helper.o cpu.o
obj-y += neon_helper.o iwmmxt_helper.o
-obj-$(TARGET_AARCH64) += advsimd_helper.o
+obj-$(TARGET_AARCH64) += advsimd_helper.o advsimd_2a_helper.o
obj-y += gdbstub.o
obj-$(TARGET_AARCH64) += cpu64.o translate-a64.o helper-a64.o gdbstub64.o
obj-y += crypto_helper.o
diff --git a/target/arm/advsimd_2a_helper.c b/target/arm/advsimd_2a_helper.c
new file mode 100644
index 0000000000..9afe16432d
--- /dev/null
+++ b/target/arm/advsimd_2a_helper.c
@@ -0,0 +1,34 @@
+/*
+ * ARM AdvancedSIMD helper functions
+ *
+ * Copyright (c) 2017 Linaro.
+ * Author: Alex Bennée <alex.ben...@linaro.org>
+ *
+ * This code is licensed under the GNU GPL v2.
+ *
+ * This code is specifically for AdvancedSIMD helpers rather than
+ * shared NEON helpers which are re-purposed for ARMv8. In practice
+ * these are helpers for newer features not found in older ARMs,
+ * currently half-precision float support.
+ *
+ * These particular helpers use the existing SoftFloat2a code
+ */
+#include "qemu/osdep.h"
+
+#include "cpu.h"
+#include "exec/exec-all.h"
+#include "exec/helper-proto.h"
+
+#define ADVSIMD_HELPER(name, suffix) HELPER(glue(glue(advsimd_, name), suffix))
+
+#define ADVSIMD_HALFOP(name) \
+float16 ADVSIMD_HELPER(name, h)(float16 a, float16 b, void *fpstp) \
+{ \
+ float_status *fpst = fpstp; \
+ return float16_ ## name(a, b, fpst); \
+}
+
+ADVSIMD_HALFOP(min)
+ADVSIMD_HALFOP(max)
+ADVSIMD_HALFOP(minnum)
+ADVSIMD_HALFOP(maxnum)
diff --git a/target/arm/helper-a64.h b/target/arm/helper-a64.h
index f4992e7b36..e99562c684 100644
--- a/target/arm/helper-a64.h
+++ b/target/arm/helper-a64.h
@@ -46,5 +46,10 @@ DEF_HELPER_FLAGS_4(paired_cmpxchg64_le, TCG_CALL_NO_WG, i64,
env, i64, i64, i64)
DEF_HELPER_FLAGS_4(paired_cmpxchg64_be, TCG_CALL_NO_WG, i64, env, i64, i64,
i64)
/* helper_advsimd.c */
+DEF_HELPER_3(advsimd_maxh, f16, f16, f16, ptr)
+DEF_HELPER_3(advsimd_minh, f16, f16, f16, ptr)
+DEF_HELPER_3(advsimd_maxnumh, f16, f16, f16, ptr)
+DEF_HELPER_3(advsimd_minnumh, f16, f16, f16, ptr)
+
DEF_HELPER_3(advsimd_acgt_f16, i32, i32, i32, ptr)
DEF_HELPER_3(advsimd_addh, f32, f32, f32, ptr)
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index c3f6080ce4..8c41f0e510 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -5659,26 +5659,80 @@ static void disas_simd_zip_trn(DisasContext *s,
uint32_t insn)
tcg_temp_free_i64(tcg_resh);
}
-static void do_minmaxop(DisasContext *s, TCGv_i32 tcg_elt1, TCGv_i32 tcg_elt2,
- int opc, bool is_min, TCGv_ptr fpst)
-{
- /* Helper function for disas_simd_across_lanes: do a single precision
- * min/max operation on the specified two inputs,
- * and return the result in tcg_elt1.
- */
- if (opc == 0xc) {
- if (is_min) {
- gen_helper_vfp_minnums(tcg_elt1, tcg_elt1, tcg_elt2, fpst);
- } else {
- gen_helper_vfp_maxnums(tcg_elt1, tcg_elt1, tcg_elt2, fpst);
- }
+/*
+ * do_reduction_op helper
+ *
+ * This mirrors the Reduce() pseudocode in the ARM ARM. It is
+ * important for correct NaN propagation that we do these
+ * operations in exactly the order specified by the pseudocode.
+ *
+ * This is a recursive function, TCG temps should be freed by the
+ * calling function once it is done with the values.
+ */
+static TCGv_i32 do_reduction_op(DisasContext *s, int fpopcode, int rn,
+ int esize, int size, int vmap, TCGv_ptr fpst)
+{
+ if (esize == size) {
+ int element;
+ TCGMemOp msize = esize == 16 ? MO_16 : MO_32;
+ TCGv_i32 tcg_elem;
+
+ /* We should have one register left here */
+ assert(ctpop8(vmap) == 1);
+ element = ctz32(vmap);
+ assert(element < 8);
+
+ tcg_elem = tcg_temp_new_i32();
+ read_vec_element_i32(s, tcg_elem, rn, element, msize);
+ return tcg_elem;
} else {
- assert(opc == 0xf);
- if (is_min) {
- gen_helper_vfp_mins(tcg_elt1, tcg_elt1, tcg_elt2, fpst);
- } else {
- gen_helper_vfp_maxs(tcg_elt1, tcg_elt1, tcg_elt2, fpst);
+ int bits = size / 2;
+ int shift = ctpop8(vmap) / 2;
+ int vmap_lo = (vmap >> shift) & vmap;
+ int vmap_hi = (vmap & ~vmap_lo);
+ TCGv_i32 tcg_hi, tcg_lo, tcg_res;
+
+ tcg_hi = do_reduction_op(s, fpopcode, rn, esize, bits, vmap_hi, fpst);
+ tcg_lo = do_reduction_op(s, fpopcode, rn, esize, bits, vmap_lo, fpst);
+ tcg_res = tcg_temp_new_i32();
+
+ /* base fpopcode = 0x0c NMV, 0x0f V
+ 0x10 MIN, 0x00 MAX
+ 0x20 F32, 0x00 FP16
+ */
+ switch(fpopcode) {
+ case 0x0c: /* fmaxnmv half-precision */
+ gen_helper_advsimd_maxnumh(tcg_res, tcg_lo, tcg_hi, fpst);
+ break;
+ case 0x0f: /* fmaxv half-precision */
+ gen_helper_advsimd_maxh(tcg_res, tcg_lo, tcg_hi, fpst);
+ break;
+ case 0x1c: /* fminnmv half-precision */
+ gen_helper_advsimd_minnumh(tcg_res, tcg_lo, tcg_hi, fpst);
+ break;
+ case 0x1f: /* fminv half-precision */
+ gen_helper_advsimd_minh(tcg_res, tcg_lo, tcg_hi, fpst);
+ break;
+ case 0x2c: /* fmaxnmv */
+ gen_helper_vfp_maxnums(tcg_res, tcg_lo, tcg_hi, fpst);
+ break;
+ case 0x2f: /* fmaxv */
+ gen_helper_vfp_maxs(tcg_res, tcg_lo, tcg_hi, fpst);
+ break;
+ case 0x3c: /* fminnmv */
+ gen_helper_vfp_minnums(tcg_res, tcg_lo, tcg_hi, fpst);
+ break;
+ case 0x3f: /* fminv */
+ gen_helper_vfp_mins(tcg_res, tcg_lo, tcg_hi, fpst);
+ break;
+ default:
+ fprintf(stderr, "%s: fpopcode %x not handled\n", __func__,
fpopcode);
+ break;
}
+
+ tcg_temp_free_i32(tcg_hi);
+ tcg_temp_free_i32(tcg_lo);
+ return tcg_res;
}
}
@@ -5720,16 +5774,21 @@ static void disas_simd_across_lanes(DisasContext *s,
uint32_t insn)
break;
case 0xc: /* FMAXNMV, FMINNMV */
case 0xf: /* FMAXV, FMINV */
- if (!is_u || !is_q || extract32(size, 0, 1)) {
- unallocated_encoding(s);
- return;
- }
- /* Bit 1 of size field encodes min vs max, and actual size is always
- * 32 bits: adjust the size variable so following code can rely on it
+ /* Bit 1 of size field encodes min vs max and the actual size
+ * depends on the encoding of the U bit. If not set (and FP16
+ * enabled) then we do half-precision float instead of single
+ * precision.
*/
is_min = extract32(size, 1, 1);
is_fp = true;
- size = 2;
+ if (!is_u && arm_dc_feature(s, ARM_FEATURE_V8_FP16)) {
+ size = 1;
+ } else if (!is_u || !is_q || extract32(size, 0, 1)) {
+ unallocated_encoding(s);
+ return;
+ } else {
+ size = 2;
+ }
break;
default:
unallocated_encoding(s);
@@ -5786,38 +5845,18 @@ static void disas_simd_across_lanes(DisasContext *s,
uint32_t insn)
}
} else {
- /* Floating point ops which work on 32 bit (single) intermediates.
+ /* Floating point vector reduction ops which work across 32
+ * bit (single) or 16 bit (half-precision) intermediates.
* Note that correct NaN propagation requires that we do these
* operations in exactly the order specified by the pseudocode.
*/
- TCGv_i32 tcg_elt1 = tcg_temp_new_i32();
- TCGv_i32 tcg_elt2 = tcg_temp_new_i32();
- TCGv_i32 tcg_elt3 = tcg_temp_new_i32();
TCGv_ptr fpst = get_fpstatus_ptr();
-
- assert(esize == 32);
- assert(elements == 4);
-
- read_vec_element(s, tcg_elt, rn, 0, MO_32);
- tcg_gen_extrl_i64_i32(tcg_elt1, tcg_elt);
- read_vec_element(s, tcg_elt, rn, 1, MO_32);
- tcg_gen_extrl_i64_i32(tcg_elt2, tcg_elt);
-
- do_minmaxop(s, tcg_elt1, tcg_elt2, opcode, is_min, fpst);
-
- read_vec_element(s, tcg_elt, rn, 2, MO_32);
- tcg_gen_extrl_i64_i32(tcg_elt2, tcg_elt);
- read_vec_element(s, tcg_elt, rn, 3, MO_32);
- tcg_gen_extrl_i64_i32(tcg_elt3, tcg_elt);
-
- do_minmaxop(s, tcg_elt2, tcg_elt3, opcode, is_min, fpst);
-
- do_minmaxop(s, tcg_elt1, tcg_elt2, opcode, is_min, fpst);
-
- tcg_gen_extu_i32_i64(tcg_res, tcg_elt1);
- tcg_temp_free_i32(tcg_elt1);
- tcg_temp_free_i32(tcg_elt2);
- tcg_temp_free_i32(tcg_elt3);
+ int fpopcode = opcode | is_min << 4 | is_u << 5;
+ int vmap = (1 << elements) - 1;
+ TCGv_i32 tcg_res32 = do_reduction_op(s, fpopcode, rn, esize,
+ (is_q ? 128 : 64), vmap, fpst);
+ tcg_gen_extu_i32_i64(tcg_res, tcg_res32);
+ tcg_temp_free_i32(tcg_res32);
tcg_temp_free_ptr(fpst);
}
@@ -5939,7 +5978,7 @@ static void handle_simd_dupg(DisasContext *s, int is_q,
int rd, int rn,
{
int size = ctz32(imm5);
int esize = 8 << size;
- int elements = (is_q ? 128 : 64)/esize;
+ int elements = (is_q ? 128 : 64) / esize;
int i = 0;
if (size > 3 || ((size == 3) && !is_q)) {
--
2.13.0
