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authorcashmere <cashmere@autistici.org>2026-09-04 09:05:24 +0200
committercashmere <cashmere@autistici.org>2026-09-04 09:05:24 +0200
commit4f49b16079b27d7ce633619e4cddfdf2bffbc952 (patch)
treec296c1e7f3c3e2f6859c6d3a1b1b208779b89679 /compat/zlib/contrib/crc32vx
downloadrelic-4f49b16079b27d7ce633619e4cddfdf2bffbc952.tar.gz
initial commitHEADmaster
Diffstat (limited to 'compat/zlib/contrib/crc32vx')
-rw-r--r--compat/zlib/contrib/crc32vx/CMakeLists.txt67
-rw-r--r--compat/zlib/contrib/crc32vx/README9
-rw-r--r--compat/zlib/contrib/crc32vx/crc32_vx.c254
-rw-r--r--compat/zlib/contrib/crc32vx/crc32_vx_hooks.h9
4 files changed, 339 insertions, 0 deletions
diff --git a/compat/zlib/contrib/crc32vx/CMakeLists.txt b/compat/zlib/contrib/crc32vx/CMakeLists.txt
new file mode 100644
index 0000000..ee46fa3
--- /dev/null
+++ b/compat/zlib/contrib/crc32vx/CMakeLists.txt
@@ -0,0 +1,67 @@
+# check if we compile for IBM s390x
+#
+CHECK_C_SOURCE_COMPILES("
+#ifndef __s390x__
+ #error
+#endif
+int main() {return 0;}
+" HAS_S390X_SUPPORT)
+
+#
+# Check for IBM S390X - VX extensions
+#
+if(ZLIB_WITH_CRC32VX AND HAS_S390X_SUPPORT)
+ # preset the compiler specific flags
+ if (CMAKE_C_COMPILER_ID STREQUAL "Clang")
+ set(VGFMAFLAG "-fzvector")
+ else()
+ set(VGFMAFLAG "-mzarch")
+ endif(CMAKE_C_COMPILER_ID STREQUAL "Clang")
+
+ set(S390X_VX_TEST
+ "#ifndef __s390x__ \n\
+ #error \n\
+ #endif \n\
+ #include <vecintrin.h> \n\
+ int main(void) { \
+ unsigned long long a __attribute__((vector_size(16))) = { 0 }; \
+ unsigned long long b __attribute__((vector_size(16))) = { 0 }; \
+ unsigned char c __attribute__((vector_size(16))) = { 0 }; \
+ c = vec_gfmsum_accum_128(a, b, c); \
+ return c[0]; \
+ }")
+
+ # cflags already contains a valid march
+ set(CMAKE_REQUIRED_FLAGS "${VGFMAFLAG}")
+ check_c_source_compiles("${S390X_VX_TEST}" HAS_S390X_VX_SUPPORT)
+ unset(CMAKE_REQUIRED_FLAGS)
+
+ # or set march for our compile units
+ if(NOT HAS_S390X_VX_SUPPORT)
+ set(CMAKE_REQUIRED_FLAGS "${VGFMAFLAG} -march=z13")
+ check_c_source_compiles("${S390X_VX_TEST}" HAS_Z13_S390X_VX_SUPPORT)
+ unset(CMAKE_REQUIRED_FLAGS )
+ list(APPEND VGFMAFLAG "-march=z13")
+ endif(NOT HAS_S390X_VX_SUPPORT)
+
+ # prepare compiling for s390x
+ if(HAS_S390X_VX_SUPPORT OR HAS_Z13_S390X_VX_SUPPORT)
+ if(ZLIB_BUILD_SHARED)
+ target_sources(zlib
+ PRIVATE
+ crc32_vx.c
+ crc32_vx_hooks.h)
+ target_compile_definitions(zlib PUBLIC -DHAVE_S390X_VX=1)
+ endif(ZLIB_BUILD_SHARED)
+ if(ZLIB_BUILD_STATIC)
+ target_sources(zlibstatic
+ PRIVATE
+ crc32_vx.c
+ crc32_vx_hooks.h)
+ target_compile_definitions(zlibstatic PUBLIC -DHAVE_S390X_VX=1)
+ endif(ZLIB_BUILD_STATIC)
+ set_source_files_properties(
+ crc32_vx.c
+ PROPERTIES COMPILE_OPTIONS "${VGFMAFLAG}")
+ endif(HAS_S390X_VX_SUPPORT OR HAS_Z13_S390X_VX_SUPPORT)
+endif(ZLIB_WITH_CRC32VX AND HAS_S390X_SUPPORT)
diff --git a/compat/zlib/contrib/crc32vx/README b/compat/zlib/contrib/crc32vx/README
new file mode 100644
index 0000000..329610d
--- /dev/null
+++ b/compat/zlib/contrib/crc32vx/README
@@ -0,0 +1,9 @@
+IBM Z mainframes starting from version z13 provide vector instructions, which
+allows vectorization of crc32. This extension is build by default when targeting
+ibm s390x. However this extension can disabled if desired:
+
+ # for configure build
+ $ ./configure --disable-crcvx
+
+ # for cmake build
+ $ cmake .. -DZLIB_CRC32VX=off
diff --git a/compat/zlib/contrib/crc32vx/crc32_vx.c b/compat/zlib/contrib/crc32vx/crc32_vx.c
new file mode 100644
index 0000000..e718e34
--- /dev/null
+++ b/compat/zlib/contrib/crc32vx/crc32_vx.c
@@ -0,0 +1,254 @@
+/*
+ * Hardware-accelerated CRC-32 variants for Linux on z Systems
+ *
+ * Use the z/Architecture Vector Extension Facility to accelerate the
+ * computing of bitreflected CRC-32 checksums.
+ *
+ * This CRC-32 implementation algorithm is bitreflected and processes
+ * the least-significant bit first (Little-Endian).
+ *
+ * This code was originally written by Hendrik Brueckner
+ * <brueckner@linux.vnet.ibm.com> for use in the Linux kernel and has been
+ * relicensed under the zlib license.
+ */
+#define Z_ONCE
+#include "../../zutil.h"
+#include "crc32_vx_hooks.h"
+
+#include <stdint.h>
+#include <stdio.h>
+#include <vecintrin.h>
+#include <sys/auxv.h>
+
+#ifdef __clang__
+# if ((__clang_major__ == 18) || (__clang_major__ == 19 && (__clang_minor__ < 1 || (__clang_minor__ == 1 && __clang_patchlevel__ < 2))))
+# error crc32_vx optimizations are broken due to compiler bug in Clang versions: 18.0.0 <= clang_version < 19.1.2. \
+ Either disable the zlib crc32_vx optimization, or switch to another compiler/compiler version.
+# endif
+#endif
+
+#define VX_MIN_LEN 64
+#define VX_ALIGNMENT 16L
+#define VX_ALIGN_MASK (VX_ALIGNMENT - 1)
+
+typedef unsigned char uv16qi __attribute__((vector_size(16)));
+typedef unsigned int uv4si __attribute__((vector_size(16)));
+typedef unsigned long long uv2di __attribute__((vector_size(16)));
+
+local uint32_t crc32_le_vgfm_16(uint32_t crc, const unsigned char *buf, size_t len) {
+ /*
+ * The CRC-32 constant block contains reduction constants to fold and
+ * process particular chunks of the input data stream in parallel.
+ *
+ * For the CRC-32 variants, the constants are precomputed according to
+ * these definitions:
+ *
+ * R1 = [(x4*128+32 mod P'(x) << 32)]' << 1
+ * R2 = [(x4*128-32 mod P'(x) << 32)]' << 1
+ * R3 = [(x128+32 mod P'(x) << 32)]' << 1
+ * R4 = [(x128-32 mod P'(x) << 32)]' << 1
+ * R5 = [(x64 mod P'(x) << 32)]' << 1
+ * R6 = [(x32 mod P'(x) << 32)]' << 1
+ *
+ * The bitreflected Barret reduction constant, u', is defined as
+ * the bit reversal of floor(x**64 / P(x)).
+ *
+ * where P(x) is the polynomial in the normal domain and the P'(x) is the
+ * polynomial in the reversed (bitreflected) domain.
+ *
+ * CRC-32 (IEEE 802.3 Ethernet, ...) polynomials:
+ *
+ * P(x) = 0x04C11DB7
+ * P'(x) = 0xEDB88320
+ */
+ const uv16qi perm_le2be = {15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0}; /* BE->LE mask */
+ const uv2di r2r1 = {0x1C6E41596, 0x154442BD4}; /* R2, R1 */
+ const uv2di r4r3 = {0x0CCAA009E, 0x1751997D0}; /* R4, R3 */
+ const uv2di r5 = {0, 0x163CD6124}; /* R5 */
+ const uv2di ru_poly = {0, 0x1F7011641}; /* u' */
+ const uv2di crc_poly = {0, 0x1DB710641}; /* P'(x) << 1 */
+
+ /*
+ * Load the initial CRC value.
+ *
+ * The CRC value is loaded into the rightmost word of the
+ * vector register and is later XORed with the LSB portion
+ * of the loaded input data.
+ */
+ uv2di v0 = {0, 0};
+ v0 = (uv2di)vec_insert(crc, (uv4si)v0, 3);
+
+ /* Load a 64-byte data chunk and XOR with CRC */
+ uv2di v1 = vec_perm(((uv2di *)buf)[0], ((uv2di *)buf)[0], perm_le2be);
+ uv2di v2 = vec_perm(((uv2di *)buf)[1], ((uv2di *)buf)[1], perm_le2be);
+ uv2di v3 = vec_perm(((uv2di *)buf)[2], ((uv2di *)buf)[2], perm_le2be);
+ uv2di v4 = vec_perm(((uv2di *)buf)[3], ((uv2di *)buf)[3], perm_le2be);
+
+ v1 ^= v0;
+ buf += 64;
+ len -= 64;
+
+ while (len >= 64) {
+ /* Load the next 64-byte data chunk */
+ uv16qi part1 = vec_perm(((uv16qi *)buf)[0], ((uv16qi *)buf)[0], perm_le2be);
+ uv16qi part2 = vec_perm(((uv16qi *)buf)[1], ((uv16qi *)buf)[1], perm_le2be);
+ uv16qi part3 = vec_perm(((uv16qi *)buf)[2], ((uv16qi *)buf)[2], perm_le2be);
+ uv16qi part4 = vec_perm(((uv16qi *)buf)[3], ((uv16qi *)buf)[3], perm_le2be);
+
+ /*
+ * Perform a GF(2) multiplication of the doublewords in V1 with
+ * the R1 and R2 reduction constants in V0. The intermediate result
+ * is then folded (accumulated) with the next data chunk in PART1 and
+ * stored in V1. Repeat this step for the register contents
+ * in V2, V3, and V4 respectively.
+ */
+ v1 = (uv2di)vec_gfmsum_accum_128(r2r1, v1, part1);
+ v2 = (uv2di)vec_gfmsum_accum_128(r2r1, v2, part2);
+ v3 = (uv2di)vec_gfmsum_accum_128(r2r1, v3, part3);
+ v4 = (uv2di)vec_gfmsum_accum_128(r2r1, v4, part4);
+
+ buf += 64;
+ len -= 64;
+ }
+
+ /*
+ * Fold V1 to V4 into a single 128-bit value in V1. Multiply V1 with R3
+ * and R4 and accumulating the next 128-bit chunk until a single 128-bit
+ * value remains.
+ */
+ v1 = (uv2di)vec_gfmsum_accum_128(r4r3, v1, (uv16qi)v2);
+ v1 = (uv2di)vec_gfmsum_accum_128(r4r3, v1, (uv16qi)v3);
+ v1 = (uv2di)vec_gfmsum_accum_128(r4r3, v1, (uv16qi)v4);
+
+ while (len >= 16) {
+ /* Load next data chunk */
+ v2 = vec_perm(*(uv2di *)buf, *(uv2di *)buf, perm_le2be);
+
+ /* Fold next data chunk */
+ v1 = (uv2di)vec_gfmsum_accum_128(r4r3, v1, (uv16qi)v2);
+
+ buf += 16;
+ len -= 16;
+ }
+
+ /*
+ * Set up a vector register for byte shifts. The shift value must
+ * be loaded in bits 1-4 in byte element 7 of a vector register.
+ * Shift by 8 bytes: 0x40
+ * Shift by 4 bytes: 0x20
+ */
+ uv16qi v9 = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+ v9 = vec_insert((unsigned char)0x40, v9, 7);
+
+ /*
+ * Prepare V0 for the next GF(2) multiplication: shift V0 by 8 bytes
+ * to move R4 into the rightmost doubleword and set the leftmost
+ * doubleword to 0x1.
+ */
+ v0 = vec_srb(r4r3, (uv2di)v9);
+ v0[0] = 1;
+
+ /*
+ * Compute GF(2) product of V1 and V0. The rightmost doubleword
+ * of V1 is multiplied with R4. The leftmost doubleword of V1 is
+ * multiplied by 0x1 and is then XORed with rightmost product.
+ * Implicitly, the intermediate leftmost product becomes padded
+ */
+ v1 = (uv2di)vec_gfmsum_128(v0, v1);
+
+ /*
+ * Now do the final 32-bit fold by multiplying the rightmost word
+ * in V1 with R5 and XOR the result with the remaining bits in V1.
+ *
+ * To achieve this by a single VGFMAG, right shift V1 by a word
+ * and store the result in V2 which is then accumulated. Use the
+ * vector unpack instruction to load the rightmost half of the
+ * doubleword into the rightmost doubleword element of V1; the other
+ * half is loaded in the leftmost doubleword.
+ * The vector register with CONST_R5 contains the R5 constant in the
+ * rightmost doubleword and the leftmost doubleword is zero to ignore
+ * the leftmost product of V1.
+ */
+ v9 = vec_insert((unsigned char)0x20, v9, 7);
+ v2 = vec_srb(v1, (uv2di)v9);
+ v1 = vec_unpackl((uv4si)v1); /* Split rightmost doubleword */
+ v1 = (uv2di)vec_gfmsum_accum_128(r5, v1, (uv16qi)v2);
+
+ /*
+ * Apply a Barret reduction to compute the final 32-bit CRC value.
+ *
+ * The input values to the Barret reduction are the degree-63 polynomial
+ * in V1 (R(x)), degree-32 generator polynomial, and the reduction
+ * constant u. The Barret reduction result is the CRC value of R(x) mod
+ * P(x).
+ *
+ * The Barret reduction algorithm is defined as:
+ *
+ * 1. T1(x) = floor( R(x) / x^32 ) GF2MUL u
+ * 2. T2(x) = floor( T1(x) / x^32 ) GF2MUL P(x)
+ * 3. C(x) = R(x) XOR T2(x) mod x^32
+ *
+ * Note: The leftmost doubleword of vector register containing
+ * CONST_RU_POLY is zero and, thus, the intermediate GF(2) product
+ * is zero and does not contribute to the final result.
+ */
+
+ /* T1(x) = floor( R(x) / x^32 ) GF2MUL u */
+ v2 = vec_unpackl((uv4si)v1);
+ v2 = (uv2di)vec_gfmsum_128(ru_poly, v2);
+
+ /*
+ * Compute the GF(2) product of the CRC polynomial with T1(x) in
+ * V2 and XOR the intermediate result, T2(x), with the value in V1.
+ * The final result is stored in word element 2 of V2.
+ */
+ v2 = vec_unpackl((uv4si)v2);
+ v2 = (uv2di)vec_gfmsum_accum_128(crc_poly, v2, (uv16qi)v1);
+
+ return ((uv4si)v2)[2];
+}
+
+
+local unsigned long s390_crc32_vx(unsigned long crc, const unsigned char FAR *buf, z_size_t len)
+{
+ uintptr_t prealign, aligned, remaining;
+
+ if (buf == Z_NULL) return 0UL;
+
+ if (len < VX_MIN_LEN + VX_ALIGN_MASK)
+ return crc32_z(crc, buf, len);
+
+ if ((uintptr_t)buf & VX_ALIGN_MASK) {
+ prealign = VX_ALIGNMENT - ((uintptr_t)buf & VX_ALIGN_MASK);
+ len -= prealign;
+ crc = crc32_z(crc, buf, prealign);
+ buf += prealign;
+ }
+ aligned = len & ~VX_ALIGN_MASK;
+ remaining = len & VX_ALIGN_MASK;
+
+ crc = crc32_le_vgfm_16(crc ^ 0xffffffff, buf, (size_t)aligned) ^ 0xffffffff;
+
+ if (remaining)
+ crc = crc32_z(crc, buf + aligned, remaining);
+
+ return crc;
+}
+
+local z_once_t s390_crc32_made = Z_ONCE_INIT;
+local void s390_crc32_setup() {
+ unsigned long hwcap = getauxval(AT_HWCAP);
+
+ if (hwcap & HWCAP_S390_VX)
+ crc32_z_hook = s390_crc32_vx;
+ else
+ crc32_z_hook = crc32_z;
+}
+
+local unsigned long s390_crc32_init(unsigned long crc, const unsigned char FAR *buf, z_size_t len)
+{
+ z_once(&s390_crc32_made,s390_crc32_setup);
+ return crc32_z_hook(crc, buf, len);
+}
+
+ZLIB_INTERNAL unsigned long (*crc32_z_hook)(unsigned long crc, const unsigned char FAR *buf, z_size_t len) = s390_crc32_init;
diff --git a/compat/zlib/contrib/crc32vx/crc32_vx_hooks.h b/compat/zlib/contrib/crc32vx/crc32_vx_hooks.h
new file mode 100644
index 0000000..951c318
--- /dev/null
+++ b/compat/zlib/contrib/crc32vx/crc32_vx_hooks.h
@@ -0,0 +1,9 @@
+#ifndef CRC32_VX_HOOKS_H
+#define CRC32_VX_HOOKS_H
+
+/**
+ * CRC HOOKS
+ */
+ZLIB_INTERNAL extern unsigned long (*crc32_z_hook)(unsigned long crc, const unsigned char FAR *buf, z_size_t len);
+
+#endif /* CRC32_VX_HOOKS_H */