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-rw-r--r--test/monniaux/BearSSL/src/int/i32_div32.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/test/monniaux/BearSSL/src/int/i32_div32.c b/test/monniaux/BearSSL/src/int/i32_div32.c
new file mode 100644
index 00000000..d8b8023d
--- /dev/null
+++ b/test/monniaux/BearSSL/src/int/i32_div32.c
@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "inner.h"
+
+/* see inner.h */
+uint32_t
+br_divrem(uint32_t hi, uint32_t lo, uint32_t d, uint32_t *r)
+{
+ /* TODO: optimize this */
+ uint32_t q;
+ uint32_t ch, cf;
+ int k;
+
+ q = 0;
+ ch = EQ(hi, d);
+ hi = MUX(ch, 0, hi);
+ for (k = 31; k > 0; k --) {
+ int j;
+ uint32_t w, ctl, hi2, lo2;
+
+ j = 32 - k;
+ w = (hi << j) | (lo >> k);
+ ctl = GE(w, d) | (hi >> k);
+ hi2 = (w - d) >> j;
+ lo2 = lo - (d << k);
+ hi = MUX(ctl, hi2, hi);
+ lo = MUX(ctl, lo2, lo);
+ q |= ctl << k;
+ }
+ cf = GE(lo, d) | hi;
+ q |= cf;
+ *r = MUX(cf, lo - d, lo);
+ return q;
+}