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Diffstat (limited to 'src/third-party/base64/lib/arch/neon32/enc_reshuffle.c')
-rw-r--r--src/third-party/base64/lib/arch/neon32/enc_reshuffle.c31
1 files changed, 31 insertions, 0 deletions
diff --git a/src/third-party/base64/lib/arch/neon32/enc_reshuffle.c b/src/third-party/base64/lib/arch/neon32/enc_reshuffle.c
new file mode 100644
index 0000000..d6e97cb
--- /dev/null
+++ b/src/third-party/base64/lib/arch/neon32/enc_reshuffle.c
@@ -0,0 +1,31 @@
+static inline uint8x16x4_t
+enc_reshuffle (uint8x16x3_t in)
+{
+ uint8x16x4_t out;
+
+ // Input:
+ // in[0] = a7 a6 a5 a4 a3 a2 a1 a0
+ // in[1] = b7 b6 b5 b4 b3 b2 b1 b0
+ // in[2] = c7 c6 c5 c4 c3 c2 c1 c0
+
+ // Output:
+ // out[0] = 00 00 a7 a6 a5 a4 a3 a2
+ // out[1] = 00 00 a1 a0 b7 b6 b5 b4
+ // out[2] = 00 00 b3 b2 b1 b0 c7 c6
+ // out[3] = 00 00 c5 c4 c3 c2 c1 c0
+
+ // Move the input bits to where they need to be in the outputs. Except
+ // for the first output, the high two bits are not cleared.
+ out.val[0] = vshrq_n_u8(in.val[0], 2);
+ out.val[1] = vshrq_n_u8(in.val[1], 4);
+ out.val[2] = vshrq_n_u8(in.val[2], 6);
+ out.val[1] = vsliq_n_u8(out.val[1], in.val[0], 4);
+ out.val[2] = vsliq_n_u8(out.val[2], in.val[1], 2);
+
+ // Clear the high two bits in the second, third and fourth output.
+ out.val[1] = vandq_u8(out.val[1], vdupq_n_u8(0x3F));
+ out.val[2] = vandq_u8(out.val[2], vdupq_n_u8(0x3F));
+ out.val[3] = vandq_u8(in.val[2], vdupq_n_u8(0x3F));
+
+ return out;
+}