x86-64: Add vector hypot/hypotf implementation to libmvec

Implement vectorized hypot/hypotf containing SSE, AVX, AVX2 and
AVX512 versions for libmvec as per vector ABI.  It also contains
accuracy and ABI tests for vector hypot/hypotf with regenerated ulps.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

1 files changed, 269 insertions, 0 deletions

diff --git a/sysdeps/x86_64/fpu/multiarch/svml_s_hypotf8_core_avx2.S b/sysdeps/x86_64/fpu/multiarch/svml_s_hypotf8_core_avx2.S
new file mode 100644
index 0000000000..733022ff01
--- /dev/null
+++ b/sysdeps/x86_64/fpu/multiarch/svml_s_hypotf8_core_avx2.S
@@ -0,0 +1,269 @@
+/* Function hypotf vectorized with AVX2.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   https://www.gnu.org/licenses/.  */
+
+/*
+ * ALGORITHM DESCRIPTION:
+ *
+ *      HIGH LEVEL OVERVIEW
+ *
+ *      Calculate z = (x*x+y*y)
+ *      Calculate reciplicle sqrt (z)
+ *      Calculate make two NR iterations
+ *
+ *      ALGORITHM DETAILS
+ *
+ *    Multiprecision branch for _HA_ only
+ *      Remove sigm from both arguments
+ *      Find maximum (_x) and minimum (_y) (by abs value) between arguments
+ *      Split _x int _a and _b for multiprecision
+ *      If _x >> _y we will we will not split _y for multiprecision
+ *      all _y will be put into lower part (_d) and higher part (_c = 0)
+ *      Fixing _hilo_mask for the case _x >> _y
+ *      Split _y into _c and _d for multiprecision with fixed mask
+ *
+ *      compute Hi and Lo parts of _z = _x*_x + _y*_y
+ *
+ *      _zHi = _a*_a + _c*_c
+ *      _zLo = (_x + _a)*_b + _d*_y + _d*_c
+ *      _z = _zHi + _zLo
+ *
+ *    No multiprecision branch for _LA_ and _EP_
+ *      _z = _VARG1 * _VARG1 + _VARG2 * _VARG2
+ *
+ *    Check _z exponent to be withing borders [1E3 ; 60A] else goto Callout
+ *
+ *    Compute resciplicle sqrt s0 ~ 1.0/sqrt(_z),
+ *      that multiplied by _z, is final result for _EP_ version.
+ *
+ *    First iteration (or zero iteration):
+ *       s =  z * s0
+ *       h = .5 * s0
+ *       d =  s *  h - .5
+ *
+ *    Second iteration:
+ *       h = d * h + h
+ *       s = s * d + s
+ *       d = s * s - z (in multiprecision for _HA_)
+ *
+ *    result = s - h * d
+ *
+ *    EP version of the function can be implemented as y[i]=sqrt(a[i]^2+b[i]^2)
+ *    with all intermediate operations done in target precision for i=1,..,n.
+ *    It can return result y[i]=0 in case a[i]^2 and b[i]^2 underflow in target
+ *    precision (for some i). It can return result y[i]=NAN in case
+ *    a[i]^2+b[i]^2 overflow in target precision, for some i. It can return
+ *    result y[i]=NAN in case a[i] or b[i] is infinite, for some i.
+ *
+ *
+ */
+
+/* Offsets for data table __svml_shypot_data_internal
+ */
+#define _sHiLoMask                    	0
+#define _sAbsMask                     	32
+#define _sHalf                        	64
+#define _LowBoundary                  	96
+#define _HighBoundary                 	128
+
+#include <sysdep.h>
+
+        .text
+	.section .text.avx2,"ax",@progbits
+ENTRY(_ZGVdN8vv_hypotf_avx2)
+        pushq     %rbp
+        cfi_def_cfa_offset(16)
+        movq      %rsp, %rbp
+        cfi_def_cfa(6, 16)
+        cfi_offset(6, -16)
+        andq      $-32, %rsp
+        subq      $128, %rsp
+
+/*
+ *  Implementation
+ * Multiprecision branch for _HA_ only
+ * No multiprecision branch for _LA_
+ * _z = _VARG1 * _VARG1 + _VARG2 * _VARG2
+ */
+        vmulps    %ymm0, %ymm0, %ymm8
+
+/*
+ *  Variables
+ *  Defines
+ *  Constants loading
+ */
+        vmovups   _sHalf+__svml_shypot_data_internal(%rip), %ymm7
+
+/* Check _z exponent to be withing borders [1E3 ; 60A] else goto Callout */
+        vmovups   _LowBoundary+__svml_shypot_data_internal(%rip), %ymm2
+        vfmadd231ps %ymm1, %ymm1, %ymm8
+
+/* _s0  ~ 1.0/sqrt(_z) */
+        vrsqrtps  %ymm8, %ymm6
+        vpcmpgtd  %ymm8, %ymm2, %ymm3
+
+/* First iteration */
+        vmulps    %ymm8, %ymm6, %ymm9
+        vmulps    %ymm7, %ymm6, %ymm2
+        vfnmadd231ps %ymm9, %ymm2, %ymm7
+        vfmadd213ps %ymm9, %ymm7, %ymm9
+
+/* Second iteration */
+        vfmadd132ps %ymm7, %ymm2, %ymm2
+        vpcmpgtd  _HighBoundary+__svml_shypot_data_internal(%rip), %ymm8, %ymm4
+        vpor      %ymm4, %ymm3, %ymm5
+
+/* Finish second iteration in native precision for _LA_ */
+        vfmsub231ps %ymm9, %ymm9, %ymm8
+        vmovmskps %ymm5, %edx
+        vfnmadd213ps %ymm9, %ymm8, %ymm2
+
+/*  The end of implementation  */
+        testl     %edx, %edx
+
+/* Go to special inputs processing branch */
+        jne       L(SPECIAL_VALUES_BRANCH)
+                                # LOE rbx r12 r13 r14 r15 edx ymm0 ymm1 ymm2
+
+/* Restore registers
+ * and exit the function
+ */
+
+L(EXIT):
+        vmovaps   %ymm2, %ymm0
+        movq      %rbp, %rsp
+        popq      %rbp
+        cfi_def_cfa(7, 8)
+        cfi_restore(6)
+        ret
+        cfi_def_cfa(6, 16)
+        cfi_offset(6, -16)
+
+/* Branch to process
+ * special inputs
+ */
+
+L(SPECIAL_VALUES_BRANCH):
+        vmovups   %ymm0, 32(%rsp)
+        vmovups   %ymm1, 64(%rsp)
+        vmovups   %ymm2, 96(%rsp)
+                                # LOE rbx r12 r13 r14 r15 edx ymm2
+
+        xorl      %eax, %eax
+                                # LOE rbx r12 r13 r14 r15 eax edx
+
+        vzeroupper
+        movq      %r12, 16(%rsp)
+        /*  DW_CFA_expression: r12 (r12) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -112; DW_OP_plus)  */
+        .cfi_escape 0x10, 0x0c, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x90, 0xff, 0xff, 0xff, 0x22
+        movl      %eax, %r12d
+        movq      %r13, 8(%rsp)
+        /*  DW_CFA_expression: r13 (r13) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -120; DW_OP_plus)  */
+        .cfi_escape 0x10, 0x0d, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x88, 0xff, 0xff, 0xff, 0x22
+        movl      %edx, %r13d
+        movq      %r14, (%rsp)
+        /*  DW_CFA_expression: r14 (r14) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -128; DW_OP_plus)  */
+        .cfi_escape 0x10, 0x0e, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x80, 0xff, 0xff, 0xff, 0x22
+                                # LOE rbx r15 r12d r13d
+
+/* Range mask
+ * bits check
+ */
+
+L(RANGEMASK_CHECK):
+        btl       %r12d, %r13d
+
+/* Call scalar math function */
+        jc        L(SCALAR_MATH_CALL)
+                                # LOE rbx r15 r12d r13d
+
+/* Special inputs
+ * processing loop
+ */
+
+L(SPECIAL_VALUES_LOOP):
+        incl      %r12d
+        cmpl      $8, %r12d
+
+/* Check bits in range mask */
+        jl        L(RANGEMASK_CHECK)
+                                # LOE rbx r15 r12d r13d
+
+        movq      16(%rsp), %r12
+        cfi_restore(12)
+        movq      8(%rsp), %r13
+        cfi_restore(13)
+        movq      (%rsp), %r14
+        cfi_restore(14)
+        vmovups   96(%rsp), %ymm2
+
+/* Go to exit */
+        jmp       L(EXIT)
+        /*  DW_CFA_expression: r12 (r12) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -112; DW_OP_plus)  */
+        .cfi_escape 0x10, 0x0c, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x90, 0xff, 0xff, 0xff, 0x22
+        /*  DW_CFA_expression: r13 (r13) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -120; DW_OP_plus)  */
+        .cfi_escape 0x10, 0x0d, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x88, 0xff, 0xff, 0xff, 0x22
+        /*  DW_CFA_expression: r14 (r14) (DW_OP_lit8; DW_OP_minus; DW_OP_const4s: -32; DW_OP_and; DW_OP_const4s: -128; DW_OP_plus)  */
+        .cfi_escape 0x10, 0x0e, 0x0e, 0x38, 0x1c, 0x0d, 0xe0, 0xff, 0xff, 0xff, 0x1a, 0x0d, 0x80, 0xff, 0xff, 0xff, 0x22
+                                # LOE rbx r12 r13 r14 r15 ymm2
+
+/* Scalar math fucntion call
+ * to process special input
+ */
+
+L(SCALAR_MATH_CALL):
+        movl      %r12d, %r14d
+        movss     32(%rsp,%r14,4), %xmm0
+        movss     64(%rsp,%r14,4), %xmm1
+        call      hypotf@PLT
+                                # LOE rbx r14 r15 r12d r13d xmm0
+
+        movss     %xmm0, 96(%rsp,%r14,4)
+
+/* Process special inputs in loop */
+        jmp       L(SPECIAL_VALUES_LOOP)
+                                # LOE rbx r15 r12d r13d
+END(_ZGVdN8vv_hypotf_avx2)
+
+        .section .rodata, "a"
+        .align 32
+
+#ifdef __svml_shypot_data_internal_typedef
+typedef unsigned int VUINT32;
+typedef struct
+{
+        __declspec(align(32)) VUINT32 _sHiLoMask[8][1];
+        __declspec(align(32)) VUINT32 _sAbsMask[8][1];
+        __declspec(align(32)) VUINT32 _sHalf[8][1];
+        __declspec(align(32)) VUINT32 _LowBoundary[8][1];
+        __declspec(align(32)) VUINT32 _HighBoundary[8][1];
+} __svml_shypot_data_internal;
+#endif
+__svml_shypot_data_internal:
+        /* legacy algorithm */
+        .long 0xFFF80000, 0xFFF80000, 0xFFF80000, 0xFFF80000, 0xFFF80000, 0xFFF80000, 0xFFF80000, 0xFFF80000  /* _sHiLoMask     */
+        .align 32
+        .long 0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff  /* _sAbsMask      */
+        .align 32
+        .long 0x3f000000, 0x3f000000, 0x3f000000, 0x3f000000, 0x3f000000, 0x3f000000, 0x3f000000, 0x3f000000  /* _sHalf         */
+        .align 32
+        .long 0x1E300000, 0x1E300000, 0x1E300000, 0x1E300000, 0x1E300000, 0x1E300000, 0x1E300000, 0x1E300000  /* _LowBoundary   */
+        .align 32
+        .long 0x60A00000, 0x60A00000, 0x60A00000, 0x60A00000, 0x60A00000, 0x60A00000, 0x60A00000, 0x60A00000  /* _HighBoundary  */
+        .align 32
+        .type	__svml_shypot_data_internal,@object
+        .size	__svml_shypot_data_internal,.-__svml_shypot_data_internal