refactoring, reduce duplicated code

base64_amd64.s

@@ -171,8 +171,8 @@ GLOBL dec_reshuffle_mask<>(SB), (NOPTR+RODATA), $16
 	VPSHUFB tmp1, lut, tmp1;                          \ // get offsets and add offsets to input value.
 	VPADDB tmp1, in_out, in_out
 
-//func encodeSIMD(dst, src []byte, lut *[16]byte) int
-TEXT ·encodeSIMD(SB),NOSPLIT,$0
+//func encodeAsm(dst, src []byte, lut *[16]byte) int
+TEXT ·encodeAsm(SB),NOSPLIT,$0
 	MOVQ dst_base+0(FP), AX
 	MOVQ src_base+24(FP), BX
 	MOVQ src_len+32(FP), CX
@@ -387,8 +387,8 @@ avx2_done:
 	VPMADDWD mask1, in_out, in_out;    \ // swap and merge 12-bit words into a 24-bit word
 	VPSHUFB mask2, in_out, in_out
 
-//func decodeStdSIMD(dst, src []byte) int
-TEXT ·decodeStdSIMD(SB),NOSPLIT,$0
+//func decodeStdAsm(dst, src []byte) int
+TEXT ·decodeStdAsm(SB),NOSPLIT,$0
 	MOVQ dst_base+0(FP), AX
 	MOVQ src_base+24(FP), BX
 	MOVQ src_len+32(FP), CX
@@ -535,8 +535,8 @@ avx2_done:
 	VZEROUPPER
 	RET
 
-//func decodeUrlSIMD(dst, src []byte) int
-TEXT ·decodeUrlSIMD(SB),NOSPLIT,$0
+//func decodeUrlAsmdst, src []byte) int
+TEXT ·decodeUrlAsm(SB),NOSPLIT,$0
 	MOVQ dst_base+0(FP), AX
 	MOVQ src_base+24(FP), BX
 	MOVQ src_len+32(FP), CX

base64_ppc64x.go → base64_asm.go

@@ -2,10 +2,15 @@
 // Use of this source code is governed by a BSD 3-Clause-style
 // license that can be found in the LICENSE file.
 
-//go:build (ppc64 || ppc64le) && !purego
+//go:build (amd64 || ppc64 || ppc64le) && !purego
 
 package base64
 
+import "golang.org/x/sys/cpu"
+
+var useAVX2 = cpu.X86.HasAVX2
+var useAVX = cpu.X86.HasAVX
+
 //go:noescape
 func encodeAsm(dst, src []byte, lut *[16]byte) int
 
@@ -35,8 +40,9 @@ func decode(enc *Encoding, dst, src []byte) (int, error) {
 		} else if enc.lut == &encodeURLLut {
 			remain = decodeUrlAsm(dst, src)
 		}
+
 		if remain < srcLen {
-			// decoded by ASM
+			// decoded by SIMD
 			remain = srcLen - remain // remain is decoded length now
 			src = src[remain:]
 			dstStart := (remain / 4) * 3

base64_amd64_test.go → base64_asm_test.go

@@ -1,4 +1,8 @@
-//go:build amd64 && !purego
+// Copyright 2024 Sun Yimin. All rights reserved.
+// Use of this source code is governed by a BSD 3-Clause-style
+// license that can be found in the LICENSE file.
+
+//go:build (amd64 || ppc64 || ppc64le) && !purego
 
 package base64