arm: ACLE BFloat16 convert intrinsics

This patch is part of a series adding support for Armv8.6-A features.
It implements intrinsics to convert between bfloat16 and float32
formats.

gcc/ChangeLog:

	* config/arm/arm_bf16.h (vcvtah_f32_bf16, vcvth_bf16_f32): New.
	* config/arm/arm_neon.h (vcvt_f32_bf16, vcvtq_low_f32_bf16): New.
	(vcvtq_high_f32_bf16, vcvt_bf16_f32): New.
	(vcvtq_low_bf16_f32, vcvtq_high_bf16_f32): New.
	* config/arm/arm_neon_builtins.def (vbfcvt, vbfcvt_high): New entries.
	(vbfcvtv4sf, vbfcvtv4sf_high): Likewise.
	* config/arm/iterators.md (VBFCVT, VBFCVTM): New mode iterators.
	(V_bf_low, V_bf_cvt_m): New mode attributes.
	* config/arm/neon.md (neon_vbfcvtv4sf<VBFCVT:mode>): New.
	(neon_vbfcvtv4sf_highv8bf, neon_vbfcvtsf): New.
	(neon_vbfcvt<VBFCVT:mode>, neon_vbfcvt_highv8bf): New.
	(neon_vbfcvtbf_cvtmode<mode>, neon_vbfcvtbf): New
	* config/arm/unspecs.md (UNSPEC_BFCVT, UNSPEC_BFCVT_HIG): New.

gcc/testsuite/ChangeLog:

	* gcc.target/arm/simd/bf16_cvt_1.c: New test.
This commit is contained in:
Dennis Zhang 2020-03-03 13:13:31 +00:00
parent 9b4f00dd3f
commit 8e6d0dba16
9 changed files with 229 additions and 0 deletions

View File

@ -1,3 +1,19 @@
2020-03-03 Dennis Zhang <dennis.zhang@arm.com>
* config/arm/arm_bf16.h (vcvtah_f32_bf16, vcvth_bf16_f32): New.
* config/arm/arm_neon.h (vcvt_f32_bf16, vcvtq_low_f32_bf16): New.
(vcvtq_high_f32_bf16, vcvt_bf16_f32): New.
(vcvtq_low_bf16_f32, vcvtq_high_bf16_f32): New.
* config/arm/arm_neon_builtins.def (vbfcvt, vbfcvt_high): New entries.
(vbfcvtv4sf, vbfcvtv4sf_high): Likewise.
* config/arm/iterators.md (VBFCVT, VBFCVTM): New mode iterators.
(V_bf_low, V_bf_cvt_m): New mode attributes.
* config/arm/neon.md (neon_vbfcvtv4sf<VBFCVT:mode>): New.
(neon_vbfcvtv4sf_highv8bf, neon_vbfcvtsf): New.
(neon_vbfcvt<VBFCVT:mode>, neon_vbfcvt_highv8bf): New.
(neon_vbfcvtbf_cvtmode<mode>, neon_vbfcvtbf): New
* config/arm/unspecs.md (UNSPEC_BFCVT, UNSPEC_BFCVT_HIG): New.
2020-03-03 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/93582

View File

@ -34,6 +34,20 @@ extern "C" {
typedef __bf16 bfloat16_t;
typedef float float32_t;
__extension__ extern __inline float32_t
__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
vcvtah_f32_bf16 (bfloat16_t __a)
{
return __builtin_neon_vbfcvtbf (__a);
}
__extension__ extern __inline bfloat16_t
__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
vcvth_bf16_f32 (float32_t __a)
{
return __builtin_neon_vbfcvtsf (__a);
}
#ifdef __cplusplus
}
#endif

View File

@ -19379,6 +19379,55 @@ vbfdotq_lane_f32 (float32x4_t __r, bfloat16x8_t __a, bfloat16x4_t __b,
#pragma GCC pop_options
#pragma GCC push_options
#pragma GCC target ("arch=armv8.2-a+bf16")
__extension__ extern __inline float32x4_t
__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
vcvt_f32_bf16 (bfloat16x4_t __a)
{
return __builtin_neon_vbfcvtv4bf (__a);
}
__extension__ extern __inline float32x4_t
__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
vcvtq_low_f32_bf16 (bfloat16x8_t __a)
{
return __builtin_neon_vbfcvtv8bf (__a);
}
__extension__ extern __inline float32x4_t
__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
vcvtq_high_f32_bf16 (bfloat16x8_t __a)
{
return __builtin_neon_vbfcvt_highv8bf (__a);
}
__extension__ extern __inline bfloat16x4_t
__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
vcvt_bf16_f32 (float32x4_t __a)
{
return __builtin_neon_vbfcvtv4sfv4bf (__a);
}
__extension__ extern __inline bfloat16x8_t
__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
vcvtq_low_bf16_f32 (float32x4_t __a)
{
return __builtin_neon_vbfcvtv4sfv8bf (__a);
}
/* The 'inactive' operand is not converted but it provides the
low 64 bits to assemble the final 128-bit result. */
__extension__ extern __inline bfloat16x8_t
__attribute__ ((__always_inline__, __gnu_inline__, __artificial__))
vcvtq_high_bf16_f32 (bfloat16x8_t inactive, float32x4_t __a)
{
return __builtin_neon_vbfcvtv4sf_highv8bf (inactive, __a);
}
#pragma GCC pop_options
#ifdef __cplusplus
}
#endif

View File

@ -385,3 +385,9 @@ VAR1 (USTERNOP, usmmla, v16qi)
VAR2 (TERNOP, vbfdot, v2sf, v4sf)
VAR2 (MAC_LANE_PAIR, vbfdot_lanev4bf, v2sf, v4sf)
VAR2 (MAC_LANE_PAIR, vbfdot_lanev8bf, v2sf, v4sf)
VAR2 (UNOP, vbfcvt, sf, bf)
VAR2 (UNOP, vbfcvt, v4bf, v8bf)
VAR1 (UNOP, vbfcvt_high, v8bf)
VAR2 (UNOP, vbfcvtv4sf, v4bf, v8bf)
VAR1 (BINOP, vbfcvtv4sf_high, v8bf)

View File

@ -229,6 +229,10 @@
;; Modes for polynomial or float values.
(define_mode_iterator VPF [V8QI V16QI V2SF V4SF])
;; Modes for BF16 convert instructions.
(define_mode_iterator VBFCVT [V4BF V8BF])
(define_mode_iterator VBFCVTM [V2SI SF])
;;----------------------------------------------------------------------------
;; Code iterators
;;----------------------------------------------------------------------------
@ -747,6 +751,12 @@
(V2SF "") (V4SF "")
(DI "_neon") (V2DI "")])
;; To select the low 64 bits of a vector.
(define_mode_attr V_bf_low [(V4BF "P") (V8BF "e")])
;; To generate intermediate modes for BF16 scalar convert.
(define_mode_attr V_bf_cvt_m [(V2SI "BF") (SF "V2SI")])
;; Scalars to be presented to scalar multiplication instructions
;; must satisfy the following constraints.

View File

@ -6660,3 +6660,80 @@ if (BYTES_BIG_ENDIAN)
}
[(set_attr "type" "neon_dot<q>")]
)
(define_insn "neon_vbfcvtv4sf<VBFCVT:mode>"
[(set (match_operand:VBFCVT 0 "register_operand" "=w")
(unspec:VBFCVT [(match_operand:V4SF 1 "register_operand" "w")]
UNSPEC_BFCVT))]
"TARGET_BF16_SIMD"
"vcvt.bf16.f32\\t%<V_bf_low>0, %q1"
[(set_attr "type" "neon_fp_cvt_narrow_s_q")]
)
(define_insn "neon_vbfcvtv4sf_highv8bf"
[(set (match_operand:V8BF 0 "register_operand" "=w")
(unspec:V8BF [(match_operand:V8BF 1 "register_operand" "0")
(match_operand:V4SF 2 "register_operand" "w")]
UNSPEC_BFCVT_HIGH))]
"TARGET_BF16_SIMD"
"vcvt.bf16.f32\\t%f0, %q2"
[(set_attr "type" "neon_fp_cvt_narrow_s_q")]
)
(define_insn "neon_vbfcvtsf"
[(set (match_operand:BF 0 "register_operand" "=t")
(unspec:BF [(match_operand:SF 1 "register_operand" "t")]
UNSPEC_BFCVT))]
"TARGET_BF16_FP"
"vcvtb.bf16.f32\\t%0, %1"
[(set_attr "type" "f_cvt")]
)
(define_insn "neon_vbfcvt<VBFCVT:mode>"
[(set (match_operand:V4SF 0 "register_operand" "=w")
(unspec:V4SF [(match_operand:VBFCVT 1 "register_operand" "w")]
UNSPEC_BFCVT))]
"TARGET_BF16_SIMD"
"vshll.u32\\t%q0, %<V_bf_low>1, #16"
[(set_attr "type" "neon_shift_imm_q")]
)
(define_insn "neon_vbfcvt_highv8bf"
[(set (match_operand:V4SF 0 "register_operand" "=w")
(unspec:V4SF [(match_operand:V8BF 1 "register_operand" "w")]
UNSPEC_BFCVT_HIGH))]
"TARGET_BF16_SIMD"
"vshll.u32\\t%q0, %f1, #16"
[(set_attr "type" "neon_shift_imm_q")]
)
;; Convert a BF scalar operand to SF via VSHL.
;; VSHL doesn't accept 32-bit registers where the BF and SF scalar operands
;; would be allocated, therefore the operands must be converted to intermediate
;; vectors (i.e. V2SI) in order to apply 64-bit registers.
(define_expand "neon_vbfcvtbf"
[(match_operand:SF 0 "register_operand")
(unspec:SF [(match_operand:BF 1 "register_operand")] UNSPEC_BFCVT)]
"TARGET_BF16_FP"
{
rtx op0 = gen_reg_rtx (V2SImode);
rtx op1 = gen_reg_rtx (V2SImode);
emit_insn (gen_neon_vbfcvtbf_cvtmodev2si (op1, operands[1]));
emit_insn (gen_neon_vshl_nv2si (op0, op1, gen_int_mode(16, SImode)));
emit_insn (gen_neon_vbfcvtbf_cvtmodesf (operands[0], op0));
DONE;
})
;; Convert BF mode to V2SI and V2SI to SF.
;; Implement this by allocating a 32-bit operand in the low half of a 64-bit
;; register indexed by a 32-bit sub-register number.
;; This will generate reloads but compiler can optimize out the moves.
;; Use 'x' constraint to guarantee the 32-bit sub-registers in an indexable
;; range so that to avoid extra moves.
(define_insn "neon_vbfcvtbf_cvtmode<mode>"
[(set (match_operand:VBFCVTM 0 "register_operand" "=x")
(unspec:VBFCVTM [(match_operand:<V_bf_cvt_m> 1 "register_operand" "0")]
UNSPEC_BFCVT))]
"TARGET_BF16_FP"
""
)

View File

@ -506,4 +506,6 @@
UNSPEC_MATMUL_S
UNSPEC_MATMUL_U
UNSPEC_MATMUL_US
UNSPEC_BFCVT
UNSPEC_BFCVT_HIGH
])

View File

@ -1,3 +1,7 @@
2020-03-03 Dennis Zhang <dennis.zhang@arm.com>
* gcc.target/arm/simd/bf16_cvt_1.c: New test.
2020-03-03 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/93582

View File

@ -0,0 +1,51 @@
/* { dg-do assemble } */
/* { dg-require-effective-target arm_v8_2a_bf16_neon_ok } */
/* { dg-options "-save-temps -O2" } */
/* { dg-add-options arm_v8_2a_bf16_neon } */
#include "arm_neon.h"
float32_t test_vcvtah_f32_bf16 (bfloat16_t a)
{
return vcvtah_f32_bf16 (a);
}
bfloat16_t test_vcvth_bf16_f32 (float32_t a)
{
return vcvth_bf16_f32 (a);
}
float32x4_t test_vcvt_f32_bf16 (bfloat16x4_t a)
{
return vcvt_f32_bf16 (a);
}
float32x4_t test_vcvtq_low_f32_bf16 (bfloat16x8_t a)
{
return vcvtq_low_f32_bf16 (a);
}
float32x4_t test_vcvtq_high_f32_bf16 (bfloat16x8_t a)
{
return vcvtq_high_f32_bf16 (a);
}
bfloat16x4_t test_vcvt_bf16_f32 (float32x4_t a)
{
return vcvt_bf16_f32 (a);
}
bfloat16x8_t test_vcvtq_low_bf16_f32 (float32x4_t a)
{
return vcvtq_low_bf16_f32 (a);
}
bfloat16x8_t test_vcvtq_high_bf16_f32 (bfloat16x8_t inactive, float32x4_t a)
{
return vcvtq_high_bf16_f32 (inactive, a);
}
/* { dg-final { scan-assembler-times {vcvtb.bf16.f32\ts[0-9]+, s[0-9]+\n} 1 } } */
/* { dg-final { scan-assembler-times {vcvt.bf16.f32\td[0-9]+, q[0-9]+\n} 3 } } */
/* { dg-final { scan-assembler-times {vshl.i32\td[0-9]+, d[0-9]+, #16} 1 } } */
/* { dg-final { scan-assembler-times {vshll.u32\tq[0-9]+, d[0-9]+, #16} 3 } } */