zstd: Add noasm tag for xxhash (#475)

Author: klauspost

zstd/internal/xxhash/xxhash_amd64.s

@@ -1,6 +1,7 @@
 // +build !appengine
 // +build gc
 // +build !purego
+// +build !noasm
 
 #include "textflag.h"
 

zstd/internal/xxhash/xxhash_arm64.s

@@ -1,13 +1,13 @@
-// +build gc,!purego
+// +build gc,!purego,!noasm
 
 #include "textflag.h"
 
 // Register allocation.
 #define digest	R1
-#define h	R2	// Return value.
-#define p	R3	// Input pointer.
+#define h	R2 // Return value.
+#define p	R3 // Input pointer.
 #define len	R4
-#define nblocks	R5	// len / 32.
+#define nblocks	R5 // len / 32.
 #define prime1	R7
 #define prime2	R8
 #define prime3	R9
@@ -22,50 +22,48 @@
 #define x3	R22
 #define x4	R23
 
-#define round(acc, x) 			\
-	MADD prime2, acc, x, acc	\
-	ROR  $64-31, acc		\
-	MUL  prime1, acc		\
+#define round(acc, x) \
+	MADD prime2, acc, x, acc \
+	ROR  $64-31, acc         \
+	MUL  prime1, acc         \
 
 // x = round(0, x).
-#define round0(x)	\
-	MUL prime2, x	\
-	ROR $64-31, x	\
-	MUL prime1, x	\
+#define round0(x) \
+	MUL prime2, x \
+	ROR $64-31, x \
+	MUL prime1, x \
 
-#define mergeRound(x)			\
-	round0(x)			\
-	EOR  x, h			\
-	MADD h, prime4, prime1, h	\
+#define mergeRound(x) \
+	round0(x)                 \
+	EOR  x, h                 \
+	MADD h, prime4, prime1, h \
 
 // Update v[1-4] with 32-byte blocks. Assumes len >= 32.
-#define blocksLoop()		\
-	LSR  $5, len, nblocks	\
-	PCALIGN $16		\
-loop:				\
-	LDP.P 32(p), (x1, x2)	\
-	round(v1, x1)		\
-	LDP  -16(p), (x3, x4)	\
-	round(v2, x2)		\
-	SUB  $1, nblocks	\
-	round(v3, x3)		\
-	round(v4, x4)		\
-	CBNZ nblocks, loop	\
-
+#define blocksLoop() \
+	LSR     $5, len, nblocks \
+	PCALIGN $16              \
+	loop:                    \
+	LDP.P   32(p), (x1, x2)  \
+	round(v1, x1)            \
+	LDP     -16(p), (x3, x4) \
+	round(v2, x2)            \
+	SUB     $1, nblocks      \
+	round(v3, x3)            \
+	round(v4, x4)            \
+	CBNZ    nblocks, loop    \
 
 // The primes are repeated here to ensure that they're stored
 // in a contiguous array, so we can load them with LDP.
-DATA  primes<> +0(SB)/8, $11400714785074694791
-DATA  primes<> +8(SB)/8, $14029467366897019727
-DATA  primes<>+16(SB)/8, $1609587929392839161
-DATA  primes<>+24(SB)/8, $9650029242287828579
-DATA  primes<>+32(SB)/8, $2870177450012600261
+DATA primes<> +0(SB)/8, $11400714785074694791
+DATA primes<> +8(SB)/8, $14029467366897019727
+DATA primes<>+16(SB)/8, $1609587929392839161
+DATA primes<>+24(SB)/8, $9650029242287828579
+DATA primes<>+32(SB)/8, $2870177450012600261
 GLOBL primes<>(SB), NOPTR+RODATA, $40
 
-
 // func Sum64(b []byte) uint64
 TEXT ·Sum64(SB), NOFRAME+NOSPLIT, $0-32
-	LDP  b_base+0(FP), (p, len)
+	LDP b_base+0(FP), (p, len)
 
 	LDP  primes<> +0(SB), (prime1, prime2)
 	LDP  primes<>+16(SB), (prime3, prime4)
@@ -156,32 +154,31 @@ try1:
 
 end:
 	EOR h >> 33, h
-	MUL prime2,  h
+	MUL prime2, h
 	EOR h >> 29, h
-	MUL prime3,  h
+	MUL prime3, h
 	EOR h >> 32, h
 
 	MOVD h, ret+24(FP)
 	RET
 
-
 // func writeBlocks(d *Digest, b []byte) int
 //
 // Assumes len(b) >= 32.
 TEXT ·writeBlocks(SB), NOFRAME+NOSPLIT, $0-40
-	LDP  primes<>(SB), (prime1, prime2)
+	LDP primes<>(SB), (prime1, prime2)
 
 	// Load state. Assume v[1-4] are stored contiguously.
 	MOVD d+0(FP), digest
-	LDP   0(digest), (v1, v2)
+	LDP  0(digest), (v1, v2)
 	LDP  16(digest), (v3, v4)
 
 	LDP b_base+8(FP), (p, len)
 
 	blocksLoop()
 
 	// Store updated state.
-	STP (v1, v2),  0(digest)
+	STP (v1, v2), 0(digest)
 	STP (v3, v4), 16(digest)
 
 	BIC  $31, len

zstd/internal/xxhash/xxhash_asm.go

@@ -1,8 +1,9 @@
-//go:build (amd64 || arm64) && !appengine && gc && !purego
+//go:build (amd64 || arm64) && !appengine && gc && !purego && !noasm
 // +build amd64 arm64
 // +build !appengine
 // +build gc
 // +build !purego
+// +build !noasm
 
 package xxhash
 

zstd/internal/xxhash/xxhash_other.go

@@ -1,5 +1,5 @@
-//go:build (!amd64 && !arm64) || appengine || !gc || purego
-// +build !amd64,!arm64 appengine !gc purego
+//go:build (!amd64 && !arm64) || appengine || !gc || purego || noasm
+// +build !amd64,!arm64 appengine !gc purego noasm
 
 package xxhash