1 files changed, 91 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/arch/x86/core/x86_bigint.c b/qemu/roms/ipxe/src/arch/x86/core/x86_bigint.c
new file mode 100644
index 000000000..418ac2309
--- /dev/null
+++ b/qemu/roms/ipxe/src/arch/x86/core/x86_bigint.c
@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2012 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdint.h>
+#include <string.h>
+#include <ipxe/bigint.h>
+
+/** @file
+ *
+ * Big integer support
+ */
+
+/**
+ * Multiply big integers
+ *
+ * @v multiplicand0	Element 0 of big integer to be multiplied
+ * @v multiplier0	Element 0 of big integer to be multiplied
+ * @v result0		Element 0 of big integer to hold result
+ * @v size		Number of elements
+ */
+void bigint_multiply_raw ( const uint32_t *multiplicand0,
+			   const uint32_t *multiplier0,
+			   uint32_t *result0, unsigned int size ) {
+	const bigint_t ( size ) __attribute__ (( may_alias )) *multiplicand =
+		( ( const void * ) multiplicand0 );
+	const bigint_t ( size ) __attribute__ (( may_alias )) *multiplier =
+		( ( const void * ) multiplier0 );
+	bigint_t ( size * 2 ) __attribute__ (( may_alias )) *result =
+		( ( void * ) result0 );
+	unsigned int i;
+	unsigned int j;
+	uint32_t multiplicand_element;
+	uint32_t multiplier_element;
+	uint32_t *result_elements;
+	uint32_t discard_a;
+	uint32_t discard_d;
+	long index;
+
+	/* Zero result */
+	memset ( result, 0, sizeof ( *result ) );
+
+	/* Multiply integers one element at a time */
+	for ( i = 0 ; i < size ; i++ ) {
+		multiplicand_element = multiplicand->element[i];
+		for ( j = 0 ; j < size ; j++ ) {
+			multiplier_element = multiplier->element[j];
+			result_elements = &result->element[ i + j ];
+			/* Perform a single multiply, and add the
+			 * resulting double-element into the result,
+			 * carrying as necessary.  The carry can
+			 * never overflow beyond the end of the
+			 * result, since:
+			 *
+			 *     a < 2^{n}, b < 2^{n} => ab < 2^{2n}
+			 */
+			__asm__ __volatile__ ( "mull %4\n\t"
+					       "addl %%eax, (%5,%2,4)\n\t"
+					       "adcl %%edx, 4(%5,%2,4)\n\t"
+					       "\n1:\n\t"
+					       "adcl $0, 8(%5,%2,4)\n\t"
+					       "inc %2\n\t"
+						       /* Does not affect CF */
+					       "jc 1b\n\t"
+					       : "=&a" ( discard_a ),
+						 "=&d" ( discard_d ),
+						 "=&r" ( index )
+					       : "0" ( multiplicand_element ),
+						 "g" ( multiplier_element ),
+						 "r" ( result_elements ),
+						 "2" ( 0 ) );
+		}
+	}
+}