+/* Copyright (c) 1998,2011,2014 Apple Inc. All Rights Reserved.
+ *
+ * NOTICE: USE OF THE MATERIALS ACCOMPANYING THIS NOTICE IS SUBJECT
+ * TO THE TERMS OF THE SIGNED "FAST ELLIPTIC ENCRYPTION (FEE) REFERENCE
+ * SOURCE CODE EVALUATION AGREEMENT" BETWEEN APPLE, INC. AND THE
+ * ORIGINAL LICENSEE THAT OBTAINED THESE MATERIALS FROM APPLE,
+ * INC. ANY USE OF THESE MATERIALS NOT PERMITTED BY SUCH AGREEMENT WILL
+ * EXPOSE YOU TO LIABILITY.
+ ***************************************************************************
+ *
+ * giantPort_PPC.c - PPC-dependent giant definitions.
+ *
+ * Revision History
+ * ----------------
+ * 10/06/98 ap
+ * Changed to compile with C++.
+ * 06 Apr 1998 at Apple
+ * Created.
+ */
+
+#include "feeDebug.h"
+#include "platform.h"
+#include "giantPort_PPC.h"
+
+#if !PPC_GIANT_PORT_INLINE
+
+
+/*
+ * Multiple-precision arithmetic routines/macros.
+ */
+
+asm giantDigit giantAddDigits(
+ register giantDigit dig1,
+ register giantDigit dig2,
+ register giantDigit *carry) /* RETURNED, 0 or 1 */
+
+{
+ /*
+ * dig1 : r3
+ * dig2 : r4
+ * carry : r5
+ * sum : r6
+ */
+
+ /* sum = dig1 + dig2 */
+ add r6, dig1, dig2;
+
+ /* if((sum < dig1) || (sum < dig2)) */
+ cmpl crf0,0,r6,dig1
+ bc 12,0,*+12
+ cmpl crf0,0,r6,dig2
+ bc 4,0,*+16
+
+ /* *carry = 1; */
+ li r7,1
+ stw r7, 0(r5)
+ b *+12
+
+ /* else *carry = 0; */
+ li r7,0
+ stw r7, 0(r5)
+
+ /* return sum in r3 */
+ mr. r3,r6
+ blr
+}
+
+/*
+ * Add a single digit value to a double digit accumulator in place.
+ * Carry out of the MSD of the accumulator is not handled.
+ * This should work any size giantDigits up to unsigned int.
+ */
+asm void giantAddDouble(
+ register giantDigit *accLow, /* IN/OUT */
+ register giantDigit *accHigh, /* IN/OUT */
+ register giantDigit val)
+{
+ /*
+ * r3 : accLow
+ * r4 : accHi
+ * r5 : val
+ * r6 : sumLo
+ * r7 : *accLow
+ */
+
+ /* giantDigit sumLo = *accLow + val; */
+ lwz r7,0(accLow)
+ add r6,r7,val
+
+ /* if((sumLo < *accLow) || (sumLo < val)) { */
+ cmpl crf0,0,r6,r7
+ bc 12,0,*+12
+ cmpl crf0,0,r6,val
+ bc 4,0,*+16
+
+ /* (*accHigh)++; */
+ lwz r7, 0(accHigh)
+ addi r7,r7,1
+ stw r7, 0(accHigh)
+
+ /* *accLow = sumLo; */
+ stw r6,0(accLow)
+ blr
+}
+
+asm giantDigit giantSubDigits(
+ register giantDigit a,
+ register giantDigit b,
+ register giantDigit *borrow) /* RETURNED, 0 or 1 */
+
+{
+ /* a : r3
+ b : r4
+ borrow : r5
+ diff : r6 */
+
+ /* giantDigit diff = a - b; */
+ subf r6, b, a;
+
+ /* if(a < b) */
+ cmpl crf0,0,a,b
+ bc 4,0,*+16
+
+ /* *borrow = 1; */
+ li r7,1
+ stw r7, 0(borrow)
+ b *+12
+
+ /* else *borrow = 0; */
+ li r7,0
+ stw r7, 0(borrow)
+
+ /* return diff in r3 */
+ mr. r3,r6
+ blr
+}
+
+asm void giantMulDigits(
+ register giantDigit dig1,
+ register giantDigit dig2,
+ register giantDigit *lowProduct, /* RETURNED, low digit */
+ register giantDigit *hiProduct) /* RETURNED, high digit */
+{
+ /* r3 : dig1
+ r4 : dig2
+ r5 : lowProduct
+ r6 : hiProduct */
+
+ /* dprod = (unsigned long long)dig1 * (unsigned long long)dig2; */
+ mullw r7, dig1, dig2 /* r7 = low(dig1 * dig2) */
+ mulhwu r8, dig1, dig2 /* r8 - hi(dig1 * dig2) */
+
+ /* *hiProduct = (giantDigit)(dprod >> GIANT_BITS_PER_DIGIT); */
+ stw r8, 0(hiProduct)
+
+ /* *lowProduct = (giantDigit)dprod; */
+ stw r7, 0(lowProduct)
+ blr
+}
+
+asm giantDigit VectorMultiply(
+ register giantDigit plierDigit, /* r3 */
+ register giantDigit *candVector, /* r4 */
+ register unsigned candLength, /* r5 */
+ register giantDigit *prodVector) /* r6 */
+{
+ register unsigned candDex; /* index into multiplicandVector */
+ register giantDigit lastCarry;
+ register giantDigit prodLo;
+ register giantDigit prodHi;
+ register unsigned scr1;
+ register unsigned sumLo;
+
+ fralloc
+
+ /* giantDigit lastCarry = 0; */
+ li lastCarry,0
+
+
+ /* for(candDex=0; candDex<candLength; ++candDex) { */
+ li candDex,0
+ b _endLoop
+
+ /*
+ * prod = *(candVector++) * plierDigit + *prodVector + lastCarry
+ */
+_topLoop:
+ lwz scr1,0(candVector) /* *candVector --> scr1 */
+ addi candVector,candVector,4 /* candVector++ */
+
+ mullw prodLo,scr1,plierDigit /* prodLo = low(*candVector * plierDigit) */
+ mulhwu prodHi,scr1,plierDigit /* prodHi = high(*candVector * plierDigit) */
+
+ /* giantAddDouble(&prodLo, &prodHi, *prodVector); */
+ lwz scr1,0(prodVector) /* *prodVector --> r9 */
+ add sumLo,prodLo,scr1 /* prodLo + *prodVector --> sumLo */
+ cmpl crf0,0,sumLo,prodLo /* sumLo < prodLo? */
+ bc 12,0,_carry1
+ cmpl crf0,0,sumLo,scr1 /* sumLo < *prodVector? */
+ bc 4,0,_noCar1
+_carry1:
+ addi prodHi,prodHi,1 /* prodHi++ */
+_noCar1:
+ mr. prodLo,sumLo /* prodLo := sumLo */
+
+ /* giantAddDouble(&prodLo, &prodHi, lastCarry); */
+ add sumLo,sumLo,lastCarry /* sumLo += lastCarry */
+ cmpl crf0,0,sumLo,prodLo /* sumLo < prodLo? */
+ bc 12,0,_carry2
+ cmpl crf0,0,sumLo,lastCarry /* sumLo < lastCarry? */
+ bc 4,0,_noCar2
+_carry2:
+ addi prodHi,prodHi,1 /* prodHi++ */
+_noCar2:
+ mr. prodLo,sumLo /* prodLo := sumLo */
+
+ /* *(prodVector++) = prodLo; */
+ stw prodLo,0(prodVector) /* prodLo --> *prodVector */
+ addi prodVector,prodVector,4 /* prodVector++ */
+
+ /* lastCarry = prodHi; */
+ mr. lastCarry,prodHi
+
+ /* } */
+ addi candDex,candDex,1 /* candDex++ */
+_endLoop:
+ cmpl crf0,0,candDex,candLength /* candDex < candLength? */
+ bc 12,0,_topLoop
+
+ /* return lastCarry; */
+ mr. r3,lastCarry /* return lastCarry in r3 */
+ frfree
+ blr
+}
+
+#endif // PPC_GIANT_PORT_INLINE
projects / apple / security.git / blobdiff