X-Git-Url: https://bearssl.org/gitweb//home/git/?p=BearSSL;a=blobdiff_plain;f=src%2Fconfig.h;h=5de3a5acf16611a602de0db7918afd1e795e7f38;hp=259f5bbb162a33503ea2305095fc9b0da4b29c49;hb=bd3036844bd20b2b8d7bce7fee5ad010ce401915;hpb=3210f38e0491b39aec1ef419cb4114e9483089fb;ds=sidebyside

diff --git a/src/config.h b/src/config.h
index 259f5bb..5de3a5a 100644
--- a/src/config.h
+++ b/src/config.h
@@ -50,6 +50,15 @@
 #define BR_SLOW_MUL   1
  */
 
+/*
+ * When BR_SLOW_MUL15 is enabled, short multplications (on 15-bit words)
+ * are assumed to be substantially slow with regards to other integer
+ * operations, thus making it worth to make more integer operations if
+ * it allows using less multiplications.
+ *
+#define BR_SLOW_MUL15   1
+ */
+
 /*
  * When BR_CT_MUL31 is enabled, multiplications of 31-bit values (used
  * in the "i31" big integer implementation) use an alternate implementation
@@ -60,6 +69,25 @@
 #define BR_CT_MUL31   1
  */
 
+/*
+ * When BR_CT_MUL15 is enabled, multiplications of 15-bit values (held
+ * in 32-bit words) use an alternate implementation which is slower and
+ * larger than the normal multiplication, but should ensure
+ * constant-time multiplications on most/all architectures where the
+ * basic multiplication is not constant-time.
+#define BR_CT_MUL15   1
+ */
+
+/*
+ * When BR_NO_ARITH_SHIFT is enabled, arithmetic right shifts (with sign
+ * extension) are performed with a sequence of operations which is bigger
+ * and slower than a simple right shift on a signed value. This avoids
+ * relying on an implementation-defined behaviour. However, most if not
+ * all C compilers use sign extension for right shifts on signed values,
+ * so this alternate macro is disabled by default.
+#define BR_NO_ARITH_SHIFT   1
+ */
+
 /*
  * When BR_USE_URANDOM is enabled, the SSL engine will use /dev/urandom
  * to automatically obtain quality randomness for seedings its internal