hash: fix CRC32c computation

[dpdk.git] / lib / librte_hash / rte_crc_arm64.h

diff --git a/lib/librte_hash/rte_crc_arm64.h b/lib/librte_hash/rte_crc_arm64.h
index 02e26bc..7dd6334 100644 (file)
--- a/lib/librte_hash/rte_crc_arm64.h
+++ b/lib/librte_hash/rte_crc_arm64.h
@@ -49,6 +49,28 @@ extern "C" {
 #include <rte_branch_prediction.h>
 #include <rte_common.h>
 
+static inline uint32_t
+crc32c_arm64_u8(uint8_t data, uint32_t init_val)
+{
+       asm(".arch armv8-a+crc");
+       __asm__ volatile(
+                       "crc32cb %w[crc], %w[crc], %w[value]"
+                       : [crc] "+r" (init_val)
+                       : [value] "r" (data));
+       return init_val;
+}
+
+static inline uint32_t
+crc32c_arm64_u16(uint16_t data, uint32_t init_val)
+{
+       asm(".arch armv8-a+crc");
+       __asm__ volatile(
+                       "crc32ch %w[crc], %w[crc], %w[value]"
+                       : [crc] "+r" (init_val)
+                       : [value] "r" (data));
+       return init_val;
+}
+
 static inline uint32_t
 crc32c_arm64_u32(uint32_t data, uint32_t init_val)
 {
@@ -102,6 +124,48 @@ rte_hash_crc_init_alg(void)
        rte_hash_crc_set_alg(CRC32_ARM64);
 }
 
+/**
+ * Use single crc32 instruction to perform a hash on a 1 byte value.
+ * Fall back to software crc32 implementation in case arm64 crc intrinsics is
+ * not supported
+ *
+ * @param data
+ *   Data to perform hash on.
+ * @param init_val
+ *   Value to initialise hash generator.
+ * @return
+ *   32bit calculated hash value.
+ */
+static inline uint32_t
+rte_hash_crc_1byte(uint8_t data, uint32_t init_val)
+{
+       if (likely(crc32_alg & CRC32_ARM64))
+               return crc32c_arm64_u8(data, init_val);
+
+       return crc32c_1byte(data, init_val);
+}
+
+/**
+ * Use single crc32 instruction to perform a hash on a 2 bytes value.
+ * Fall back to software crc32 implementation in case arm64 crc intrinsics is
+ * not supported
+ *
+ * @param data
+ *   Data to perform hash on.
+ * @param init_val
+ *   Value to initialise hash generator.
+ * @return
+ *   32bit calculated hash value.
+ */
+static inline uint32_t
+rte_hash_crc_2byte(uint16_t data, uint32_t init_val)
+{
+       if (likely(crc32_alg & CRC32_ARM64))
+               return crc32c_arm64_u16(data, init_val);
+
+       return crc32c_2bytes(data, init_val);
+}
+
 /**
  * Use single crc32 instruction to perform a hash on a 4 byte value.
  * Fall back to software crc32 implementation in case arm64 crc intrinsics is