mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-07-17 20:29:31 +00:00
As Reid suggested, fixed some problems.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33955 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Zhou Sheng
parent
7406dcdc29
commit
353815dc19
@ -24,6 +24,247 @@
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#include <cstdlib>
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using namespace llvm;
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/// mul_1 - This function performs the multiplication operation on a
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/// large integer (represented as an integer array) and a uint64_t integer.
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/// @returns the carry of the multiplication.
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static uint64_t mul_1(uint64_t dest[], uint64_t x[],
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unsigned len, uint64_t y) {
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// Split y into high 32-bit part and low 32-bit part.
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uint64_t ly = y & 0xffffffffULL, hy = y >> 32;
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uint64_t carry = 0, lx, hx;
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for (unsigned i = 0; i < len; ++i) {
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lx = x[i] & 0xffffffffULL;
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hx = x[i] >> 32;
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// hasCarry - A flag to indicate if has carry.
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// hasCarry == 0, no carry
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// hasCarry == 1, has carry
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// hasCarry == 2, no carry and the calculation result == 0.
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uint8_t hasCarry = 0;
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dest[i] = carry + lx * ly;
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// Determine if the add above introduces carry.
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hasCarry = (dest[i] < carry) ? 1 : 0;
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carry = hx * ly + (dest[i] >> 32) + (hasCarry ? (1ULL << 32) : 0);
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// The upper limit of carry can be (2^32 - 1)(2^32 - 1) +
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// (2^32 - 1) + 2^32 = 2^64.
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hasCarry = (!carry && hasCarry) ? 1 : (!carry ? 2 : 0);
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carry += (lx * hy) & 0xffffffffULL;
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dest[i] = (carry << 32) | (dest[i] & 0xffffffffULL);
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carry = (((!carry && hasCarry != 2) || hasCarry == 1) ? (1ULL << 32) : 0) +
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(carry >> 32) + ((lx * hy) >> 32) + hx * hy;
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}
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return carry;
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}
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/// mul - This function multiplies integer array x[] by integer array y[] and
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/// stores the result into integer array dest[].
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/// Note the array dest[]'s size should no less than xlen + ylen.
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static void mul(uint64_t dest[], uint64_t x[], unsigned xlen,
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uint64_t y[], unsigned ylen) {
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dest[xlen] = mul_1(dest, x, xlen, y[0]);
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for (unsigned i = 1; i < ylen; ++i) {
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uint64_t ly = y[i] & 0xffffffffULL, hy = y[i] >> 32;
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uint64_t carry = 0, lx, hx;
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for (unsigned j = 0; j < xlen; ++j) {
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lx = x[j] & 0xffffffffULL;
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hx = x[j] >> 32;
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// hasCarry - A flag to indicate if has carry.
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// hasCarry == 0, no carry
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// hasCarry == 1, has carry
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// hasCarry == 2, no carry and the calculation result == 0.
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uint8_t hasCarry = 0;
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uint64_t resul = carry + lx * ly;
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hasCarry = (resul < carry) ? 1 : 0;
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carry = (hasCarry ? (1ULL << 32) : 0) + hx * ly + (resul >> 32);
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hasCarry = (!carry && hasCarry) ? 1 : (!carry ? 2 : 0);
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carry += (lx * hy) & 0xffffffffULL;
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resul = (carry << 32) | (resul & 0xffffffffULL);
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dest[i+j] += resul;
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carry = (((!carry && hasCarry != 2) || hasCarry == 1) ? (1ULL << 32) : 0)+
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(carry >> 32) + (dest[i+j] < resul ? 1 : 0) +
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((lx * hy) >> 32) + hx * hy;
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}
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dest[i+xlen] = carry;
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}
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}
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/// add_1 - This function adds the integer array x[] by integer y and
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/// returns the carry.
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/// @returns the carry of the addition.
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static uint64_t add_1(uint64_t dest[], uint64_t x[],
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unsigned len, uint64_t y) {
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uint64_t carry = y;
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for (unsigned i = 0; i < len; ++i) {
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dest[i] = carry + x[i];
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carry = (dest[i] < carry) ? 1 : 0;
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}
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return carry;
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}
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/// add - This function adds the integer array x[] by integer array
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/// y[] and returns the carry.
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static uint64_t add(uint64_t dest[], uint64_t x[],
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uint64_t y[], unsigned len) {
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unsigned carry = 0;
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for (unsigned i = 0; i< len; ++i) {
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carry += x[i];
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dest[i] = carry + y[i];
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carry = carry < x[i] ? 1 : (dest[i] < carry ? 1 : 0);
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}
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return carry;
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}
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/// sub_1 - This function subtracts the integer array x[] by
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/// integer y and returns the borrow-out carry.
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static uint64_t sub_1(uint64_t x[], unsigned len, uint64_t y) {
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uint64_t cy = y;
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for (unsigned i = 0; i < len; ++i) {
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uint64_t X = x[i];
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x[i] -= cy;
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if (cy > X)
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cy = 1;
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else {
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cy = 0;
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break;
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}
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}
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return cy;
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}
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/// sub - This function subtracts the integer array x[] by
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/// integer array y[], and returns the borrow-out carry.
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static uint64_t sub(uint64_t dest[], uint64_t x[],
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uint64_t y[], unsigned len) {
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// Carry indicator.
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uint64_t cy = 0;
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for (unsigned i = 0; i < len; ++i) {
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uint64_t Y = y[i], X = x[i];
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Y += cy;
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cy = Y < cy ? 1 : 0;
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Y = X - Y;
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cy += Y > X ? 1 : 0;
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dest[i] = Y;
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}
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return cy;
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}
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/// UnitDiv - This function divides N by D,
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/// and returns (remainder << 32) | quotient.
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/// Assumes (N >> 32) < D.
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static uint64_t unitDiv(uint64_t N, unsigned D) {
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uint64_t q, r; // q: quotient, r: remainder.
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uint64_t a1 = N >> 32; // a1: high 32-bit part of N.
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uint64_t a0 = N & 0xffffffffL; // a0: low 32-bit part of N
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if (a1 < ((D - a1 - (a0 >> 31)) & 0xffffffffL)) {
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q = N / D;
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r = N % D;
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}
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else {
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// Compute c1*2^32 + c0 = a1*2^32 + a0 - 2^31*d
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uint64_t c = N - ((uint64_t) D << 31);
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// Divide (c1*2^32 + c0) by d
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q = c / D;
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r = c % D;
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// Add 2^31 to quotient
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q += 1 << 31;
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}
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return (r << 32) | (q & 0xFFFFFFFFl);
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}
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/// subMul - This function substracts x[len-1:0] * y from
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/// dest[offset+len-1:offset], and returns the most significant
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/// word of the product, minus the borrow-out from the subtraction.
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static unsigned subMul(unsigned dest[], unsigned offset,
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unsigned x[], unsigned len, unsigned y) {
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uint64_t yl = (uint64_t) y & 0xffffffffL;
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unsigned carry = 0;
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unsigned j = 0;
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do {
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uint64_t prod = ((uint64_t) x[j] & 0xffffffffL) * yl;
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unsigned prod_low = (unsigned) prod;
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unsigned prod_high = (unsigned) (prod >> 32);
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prod_low += carry;
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carry = (prod_low < carry ? 1 : 0) + prod_high;
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unsigned x_j = dest[offset+j];
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prod_low = x_j - prod_low;
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if (prod_low > x_j) ++carry;
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dest[offset+j] = prod_low;
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} while (++j < len);
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return carry;
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}
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/// div - This is basically Knuth's formulation of the classical algorithm.
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/// Correspondance with Knuth's notation:
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/// Knuth's u[0:m+n] == zds[nx:0].
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/// Knuth's v[1:n] == y[ny-1:0]
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/// Knuth's n == ny.
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/// Knuth's m == nx-ny.
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/// Our nx == Knuth's m+n.
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/// Could be re-implemented using gmp's mpn_divrem:
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/// zds[nx] = mpn_divrem (&zds[ny], 0, zds, nx, y, ny).
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static void div(unsigned zds[], unsigned nx, unsigned y[], unsigned ny) {
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unsigned j = nx;
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do { // loop over digits of quotient
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// Knuth's j == our nx-j.
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// Knuth's u[j:j+n] == our zds[j:j-ny].
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unsigned qhat; // treated as unsigned
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if (zds[j] == y[ny-1]) qhat = -1U; // 0xffffffff
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else {
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uint64_t w = (((uint64_t)(zds[j])) << 32) +
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((uint64_t)zds[j-1] & 0xffffffffL);
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qhat = (unsigned) unitDiv(w, y[ny-1]);
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}
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if (qhat) {
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unsigned borrow = subMul(zds, j - ny, y, ny, qhat);
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unsigned save = zds[j];
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uint64_t num = ((uint64_t)save&0xffffffffL) -
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((uint64_t)borrow&0xffffffffL);
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while (num) {
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qhat--;
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uint64_t carry = 0;
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for (unsigned i = 0; i < ny; i++) {
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carry += ((uint64_t) zds[j-ny+i] & 0xffffffffL)
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+ ((uint64_t) y[i] & 0xffffffffL);
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zds[j-ny+i] = (unsigned) carry;
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carry >>= 32;
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}
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zds[j] += carry;
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num = carry - 1;
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}
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}
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zds[j] = qhat;
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} while (--j >= ny);
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}
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/// lshift - This function shift x[0:len-1] left by shiftAmt bits, and
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/// store the len least significant words of the result in
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/// dest[d_offset:d_offset+len-1]. It returns the bits shifted out from
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/// the most significant digit.
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static uint64_t lshift(uint64_t dest[], unsigned d_offset,
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uint64_t x[], unsigned len, unsigned shiftAmt) {
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unsigned count = 64 - shiftAmt;
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int i = len - 1;
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uint64_t high_word = x[i], retVal = high_word >> count;
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++d_offset;
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while (--i >= 0) {
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uint64_t low_word = x[i];
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dest[d_offset+i] = (high_word << shiftAmt) | (low_word >> count);
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high_word = low_word;
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}
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dest[d_offset+i] = high_word << shiftAmt;
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return retVal;
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}
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APInt::APInt(uint64_t val, unsigned numBits, bool sign)
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: bitsnum(numBits), isSigned(sign) {
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assert(bitsnum >= IntegerType::MIN_INT_BITS && "bitwidth too small");
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@ -153,254 +394,6 @@ APInt::~APInt() {
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inline unsigned APInt::whichByte(unsigned bitPosition)
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{ return (bitPosition % APINT_BITS_PER_WORD) / 8; }
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/// getWord - returns the corresponding word for the specified bit position.
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inline uint64_t& APInt::getWord(unsigned bitPosition)
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{ return isSingleWord() ? VAL : pVal[whichWord(bitPosition)]; }
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/// getWord - returns the corresponding word for the specified bit position.
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/// This is a constant version.
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inline uint64_t APInt::getWord(unsigned bitPosition) const
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{ return isSingleWord() ? VAL : pVal[whichWord(bitPosition)]; }
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/// mul_1 - This function multiplies the integer array x[] by a integer y and
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/// returns the carry.
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uint64_t APInt::mul_1(uint64_t dest[], uint64_t x[],
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unsigned len, uint64_t y) {
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// Split y into high 32-bit part and low 32-bit part.
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uint64_t ly = y & 0xffffffffULL, hy = y >> 32;
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uint64_t carry = 0, lx, hx;
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for (unsigned i = 0; i < len; ++i) {
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lx = x[i] & 0xffffffffULL;
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hx = x[i] >> 32;
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// hasCarry - A flag to indicate if has carry.
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// hasCarry == 0, no carry
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// hasCarry == 1, has carry
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// hasCarry == 2, no carry and the calculation result == 0.
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uint8_t hasCarry = 0;
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dest[i] = carry + lx * ly;
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// Determine if the add above introduces carry.
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hasCarry = (dest[i] < carry) ? 1 : 0;
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carry = hx * ly + (dest[i] >> 32) + (hasCarry ? (1ULL << 32) : 0);
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// The upper limit of carry can be (2^32 - 1)(2^32 - 1) +
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// (2^32 - 1) + 2^32 = 2^64.
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hasCarry = (!carry && hasCarry) ? 1 : (!carry ? 2 : 0);
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carry += (lx * hy) & 0xffffffffULL;
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dest[i] = (carry << 32) | (dest[i] & 0xffffffffULL);
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carry = (((!carry && hasCarry != 2) || hasCarry == 1) ? (1ULL << 32) : 0) +
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(carry >> 32) + ((lx * hy) >> 32) + hx * hy;
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}
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return carry;
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}
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/// mul - This function multiplies integer array x[] by integer array y[] and
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/// stores the result into integer array dest[].
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/// Note the array dest[]'s size should no less than xlen + ylen.
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void APInt::mul(uint64_t dest[], uint64_t x[], unsigned xlen,
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uint64_t y[], unsigned ylen) {
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dest[xlen] = mul_1(dest, x, xlen, y[0]);
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for (unsigned i = 1; i < ylen; ++i) {
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uint64_t ly = y[i] & 0xffffffffULL, hy = y[i] >> 32;
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uint64_t carry = 0, lx, hx;
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for (unsigned j = 0; j < xlen; ++j) {
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lx = x[j] & 0xffffffffULL;
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hx = x[j] >> 32;
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// hasCarry - A flag to indicate if has carry.
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// hasCarry == 0, no carry
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// hasCarry == 1, has carry
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// hasCarry == 2, no carry and the calculation result == 0.
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uint8_t hasCarry = 0;
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uint64_t resul = carry + lx * ly;
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hasCarry = (resul < carry) ? 1 : 0;
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carry = (hasCarry ? (1ULL << 32) : 0) + hx * ly + (resul >> 32);
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hasCarry = (!carry && hasCarry) ? 1 : (!carry ? 2 : 0);
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carry += (lx * hy) & 0xffffffffULL;
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resul = (carry << 32) | (resul & 0xffffffffULL);
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dest[i+j] += resul;
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carry = (((!carry && hasCarry != 2) || hasCarry == 1) ? (1ULL << 32) : 0)+
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(carry >> 32) + (dest[i+j] < resul ? 1 : 0) +
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((lx * hy) >> 32) + hx * hy;
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}
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dest[i+xlen] = carry;
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}
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}
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/// add_1 - This function adds the integer array x[] by integer y and
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/// returns the carry.
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uint64_t APInt::add_1(uint64_t dest[], uint64_t x[],
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unsigned len, uint64_t y) {
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uint64_t carry = y;
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for (unsigned i = 0; i < len; ++i) {
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dest[i] = carry + x[i];
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carry = (dest[i] < carry) ? 1 : 0;
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}
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return carry;
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}
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/// add - This function adds the integer array x[] by integer array
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/// y[] and returns the carry.
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uint64_t APInt::add(uint64_t dest[], uint64_t x[],
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uint64_t y[], unsigned len) {
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unsigned carry = 0;
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for (unsigned i = 0; i< len; ++i) {
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carry += x[i];
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dest[i] = carry + y[i];
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carry = carry < x[i] ? 1 : (dest[i] < carry ? 1 : 0);
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}
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return carry;
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}
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/// sub_1 - This function subtracts the integer array x[] by
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/// integer y and returns the borrow-out carry.
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uint64_t APInt::sub_1(uint64_t x[], unsigned len, uint64_t y) {
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uint64_t cy = y;
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for (unsigned i = 0; i < len; ++i) {
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uint64_t X = x[i];
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x[i] -= cy;
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if (cy > X)
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cy = 1;
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else {
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cy = 0;
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break;
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}
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}
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return cy;
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}
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/// sub - This function subtracts the integer array x[] by
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/// integer array y[], and returns the borrow-out carry.
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uint64_t APInt::sub(uint64_t dest[], uint64_t x[],
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uint64_t y[], unsigned len) {
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// Carry indicator.
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uint64_t cy = 0;
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for (unsigned i = 0; i < len; ++i) {
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uint64_t Y = y[i], X = x[i];
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Y += cy;
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cy = Y < cy ? 1 : 0;
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Y = X - Y;
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cy += Y > X ? 1 : 0;
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dest[i] = Y;
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}
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return cy;
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}
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/// UnitDiv - This function divides N by D,
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/// and returns (remainder << 32) | quotient.
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/// Assumes (N >> 32) < D.
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uint64_t APInt::unitDiv(uint64_t N, unsigned D) {
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uint64_t q, r; // q: quotient, r: remainder.
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uint64_t a1 = N >> 32; // a1: high 32-bit part of N.
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uint64_t a0 = N & 0xffffffffL; // a0: low 32-bit part of N
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if (a1 < ((D - a1 - (a0 >> 31)) & 0xffffffffL)) {
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q = N / D;
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r = N % D;
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}
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else {
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// Compute c1*2^32 + c0 = a1*2^32 + a0 - 2^31*d
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uint64_t c = N - ((uint64_t) D << 31);
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// Divide (c1*2^32 + c0) by d
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q = c / D;
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r = c % D;
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// Add 2^31 to quotient
|
||||
q += 1 << 31;
|
||||
}
|
||||
|
||||
return (r << 32) | (q & 0xFFFFFFFFl);
|
||||
}
|
||||
|
||||
/// subMul - This function substracts x[len-1:0] * y from
|
||||
/// dest[offset+len-1:offset], and returns the most significant
|
||||
/// word of the product, minus the borrow-out from the subtraction.
|
||||
unsigned APInt::subMul(unsigned dest[], unsigned offset,
|
||||
unsigned x[], unsigned len, unsigned y) {
|
||||
uint64_t yl = (uint64_t) y & 0xffffffffL;
|
||||
unsigned carry = 0;
|
||||
unsigned j = 0;
|
||||
do {
|
||||
uint64_t prod = ((uint64_t) x[j] & 0xffffffffL) * yl;
|
||||
unsigned prod_low = (unsigned) prod;
|
||||
unsigned prod_high = (unsigned) (prod >> 32);
|
||||
prod_low += carry;
|
||||
carry = (prod_low < carry ? 1 : 0) + prod_high;
|
||||
unsigned x_j = dest[offset+j];
|
||||
prod_low = x_j - prod_low;
|
||||
if (prod_low > x_j) ++carry;
|
||||
dest[offset+j] = prod_low;
|
||||
} while (++j < len);
|
||||
return carry;
|
||||
}
|
||||
|
||||
/// div - This is basically Knuth's formulation of the classical algorithm.
|
||||
/// Correspondance with Knuth's notation:
|
||||
/// Knuth's u[0:m+n] == zds[nx:0].
|
||||
/// Knuth's v[1:n] == y[ny-1:0]
|
||||
/// Knuth's n == ny.
|
||||
/// Knuth's m == nx-ny.
|
||||
/// Our nx == Knuth's m+n.
|
||||
/// Could be re-implemented using gmp's mpn_divrem:
|
||||
/// zds[nx] = mpn_divrem (&zds[ny], 0, zds, nx, y, ny).
|
||||
void APInt::div(unsigned zds[], unsigned nx, unsigned y[], unsigned ny) {
|
||||
unsigned j = nx;
|
||||
do { // loop over digits of quotient
|
||||
// Knuth's j == our nx-j.
|
||||
// Knuth's u[j:j+n] == our zds[j:j-ny].
|
||||
unsigned qhat; // treated as unsigned
|
||||
if (zds[j] == y[ny-1]) qhat = -1U; // 0xffffffff
|
||||
else {
|
||||
uint64_t w = (((uint64_t)(zds[j])) << 32) +
|
||||
((uint64_t)zds[j-1] & 0xffffffffL);
|
||||
qhat = (unsigned) unitDiv(w, y[ny-1]);
|
||||
}
|
||||
if (qhat) {
|
||||
unsigned borrow = subMul(zds, j - ny, y, ny, qhat);
|
||||
unsigned save = zds[j];
|
||||
uint64_t num = ((uint64_t)save&0xffffffffL) -
|
||||
((uint64_t)borrow&0xffffffffL);
|
||||
while (num) {
|
||||
qhat--;
|
||||
uint64_t carry = 0;
|
||||
for (unsigned i = 0; i < ny; i++) {
|
||||
carry += ((uint64_t) zds[j-ny+i] & 0xffffffffL)
|
||||
+ ((uint64_t) y[i] & 0xffffffffL);
|
||||
zds[j-ny+i] = (unsigned) carry;
|
||||
carry >>= 32;
|
||||
}
|
||||
zds[j] += carry;
|
||||
num = carry - 1;
|
||||
}
|
||||
}
|
||||
zds[j] = qhat;
|
||||
} while (--j >= ny);
|
||||
}
|
||||
|
||||
/// lshift - This function shift x[0:len-1] left by shiftAmt bits, and
|
||||
/// store the len least significant words of the result in
|
||||
/// dest[d_offset:d_offset+len-1]. It returns the bits shifted out from
|
||||
/// the most significant digit.
|
||||
uint64_t APInt::lshift(uint64_t dest[], unsigned d_offset,
|
||||
uint64_t x[], unsigned len, unsigned shiftAmt) {
|
||||
unsigned count = 64 - shiftAmt;
|
||||
int i = len - 1;
|
||||
uint64_t high_word = x[i], retVal = high_word >> count;
|
||||
++d_offset;
|
||||
while (--i >= 0) {
|
||||
uint64_t low_word = x[i];
|
||||
dest[d_offset+i] = (high_word << shiftAmt) | (low_word >> count);
|
||||
high_word = low_word;
|
||||
}
|
||||
dest[d_offset+i] = high_word << shiftAmt;
|
||||
return retVal;
|
||||
}
|
||||
|
||||
/// @brief Copy assignment operator. Create a new object from the given
|
||||
/// APInt one by initialization.
|
||||
APInt& APInt::operator=(const APInt& RHS) {
|
||||
|
||||
Loading…
Reference in New Issue
Block a user