check in v3.8.1 source

crypto/bn/arch/arm/bn_arch.h

@@ -0,0 +1,73 @@
+/*	$OpenBSD: bn_arch.h,v 1.2 2023/06/24 15:51:47 jsing Exp $ */
+/*
+ * Copyright (c) 2023 Joel Sing <jsing@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <openssl/bn.h>
+
+#ifndef HEADER_BN_ARCH_H
+#define HEADER_BN_ARCH_H
+
+#ifndef OPENSSL_NO_ASM
+
+#if defined(__GNUC__)
+
+#define HAVE_BN_SUBW
+
+static inline void
+bn_subw(BN_ULONG a, BN_ULONG b, BN_ULONG *out_borrow, BN_ULONG *out_r0)
+{
+	BN_ULONG borrow, r0;
+
+	__asm__ (
+	    "mov  %[borrow], #0 \n"
+	    "subs %[r0], %[a], %[b] \n"
+	    "sbc  %[borrow], %[borrow], #0 \n"
+	    "neg  %[borrow], %[borrow] \n"
+	    : [borrow]"=&r"(borrow), [r0]"=r"(r0)
+	    : [a]"r"(a), [b]"r"(b)
+	    : "cc");
+
+	*out_borrow = borrow;
+	*out_r0 = r0;
+}
+
+#define HAVE_BN_SUBW_SUBW
+
+static inline void
+bn_subw_subw(BN_ULONG a, BN_ULONG b, BN_ULONG c, BN_ULONG *out_borrow,
+    BN_ULONG *out_r0)
+{
+	BN_ULONG borrow, r0;
+
+	__asm__ (
+	    "mov  %[borrow], #0 \n"
+	    "subs %[r0], %[a], %[b] \n"
+	    "sbc  %[borrow], %[borrow], #0 \n"
+	    "subs %[r0], %[r0], %[c] \n"
+	    "sbc  %[borrow], %[borrow], #0 \n"
+	    "neg  %[borrow], %[borrow] \n"
+	    : [borrow]"=&r"(borrow), [r0]"=&r"(r0)
+	    : [a]"r"(a), [b]"r"(b), [c]"r"(c)
+	    : "cc");
+
+	*out_borrow = borrow;
+	*out_r0 = r0;
+}
+
+#endif /* __GNUC__ */
+
+#endif
+#endif