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diff --git a/third_party/webrtc/src/webrtc/common_audio/signal_processing/spl_sqrt_floor_mips.c b/third_party/webrtc/src/webrtc/common_audio/signal_processing/spl_sqrt_floor_mips.c
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+++ b/third_party/webrtc/src/webrtc/common_audio/signal_processing/spl_sqrt_floor_mips.c
@@ -0,0 +1,207 @@
+/*
+ * Written by Wilco Dijkstra, 1996. The following email exchange establishes the
+ * license.
+ *
+ * From: Wilco Dijkstra <Wilco.Dijkstra@ntlworld.com>
+ * Date: Fri, Jun 24, 2011 at 3:20 AM
+ * Subject: Re: sqrt routine
+ * To: Kevin Ma <kma@google.com>
+ * Hi Kevin,
+ * Thanks for asking. Those routines are public domain (originally posted to
+ * comp.sys.arm a long time ago), so you can use them freely for any purpose.
+ * Cheers,
+ * Wilco
+ *
+ * ----- Original Message -----
+ * From: "Kevin Ma" <kma@google.com>
+ * To: <Wilco.Dijkstra@ntlworld.com>
+ * Sent: Thursday, June 23, 2011 11:44 PM
+ * Subject: Fwd: sqrt routine
+ * Hi Wilco,
+ * I saw your sqrt routine from several web sites, including
+ * http://www.finesse.demon.co.uk/steven/sqrt.html.
+ * Just wonder if there's any copyright information with your Successive
+ * approximation routines, or if I can freely use it for any purpose.
+ * Thanks.
+ * Kevin
+ */
+
+// Minor modifications in code style for WebRTC, 2012.
+// Code optimizations for MIPS, 2013.
+
+#include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
+
+/*
+ * Algorithm:
+ * Successive approximation of the equation (root + delta) ^ 2 = N
+ * until delta < 1. If delta < 1 we have the integer part of SQRT (N).
+ * Use delta = 2^i for i = 15 .. 0.
+ *
+ * Output precision is 16 bits. Note for large input values (close to
+ * 0x7FFFFFFF), bit 15 (the highest bit of the low 16-bit half word)
+ * contains the MSB information (a non-sign value). Do with caution
+ * if you need to cast the output to int16_t type.
+ *
+ * If the input value is negative, it returns 0.
+ */
+
+
+int32_t WebRtcSpl_SqrtFloor(int32_t value)
+{
+ int32_t root = 0, tmp1, tmp2, tmp3, tmp4;
+
+ __asm __volatile(
+ ".set push \n\t"
+ ".set noreorder \n\t"
+
+ "lui %[tmp1], 0x4000 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "sub %[tmp3], %[value], %[tmp1] \n\t"
+ "lui %[tmp1], 0x1 \n\t"
+ "or %[tmp4], %[root], %[tmp1] \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x4000 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 14 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x8000 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x2000 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 13 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x4000 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x1000 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 12 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x2000 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x800 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 11 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x1000 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x400 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 10 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x800 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x200 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 9 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x400 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x100 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 8 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x200 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x80 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 7 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x100 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x40 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 6 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x80 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x20 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 5 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x40 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x10 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 4 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x20 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x8 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 3 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x10 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x4 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 2 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x8 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x2 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "sll %[tmp1], 1 \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "subu %[tmp3], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x4 \n\t"
+ "movz %[value], %[tmp3], %[tmp2] \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ "addiu %[tmp1], $0, 0x1 \n\t"
+ "addu %[tmp1], %[tmp1], %[root] \n\t"
+ "slt %[tmp2], %[value], %[tmp1] \n\t"
+ "ori %[tmp4], %[root], 0x2 \n\t"
+ "movz %[root], %[tmp4], %[tmp2] \n\t"
+
+ ".set pop \n\t"
+
+ : [root] "+r" (root), [value] "+r" (value),
+ [tmp1] "=&r" (tmp1), [tmp2] "=&r" (tmp2),
+ [tmp3] "=&r" (tmp3), [tmp4] "=&r" (tmp4)
+ :
+ );
+
+ return root >> 1;
+}
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-24 13:04:55 +0000