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[APInt] Use Lo_32/Hi_32/Make_64 in a few more places in the divide code. NFCI 

llvm-svn: 302983
This commit is contained in:
Craig Topper 2017-05-13 07:14:17 +00:00
parent 935f7b050f
commit 2c9a70661c
1 changed files with 6 additions and 6 deletions
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12
llvm/lib/Support/APInt.cpp
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@ -1306,7 +1306,7 @@ static void KnuthDiv(uint32_t *u, uint32_t *v, uint32_t *q, uint32_t* r,
// on v[n-2] determines at high speed most of the cases in which the trial // on v[n-2] determines at high speed most of the cases in which the trial
// value qp is one too large, and it eliminates all cases where qp is two // value qp is one too large, and it eliminates all cases where qp is two
// too large. // too large.
uint64_t dividend = ((uint64_t(u[j+n]) << 32) + u[j+n-1]); uint64_t dividend = Make_64(u[j+n], u[j+n-1]);
DEBUG(dbgs() << "KnuthDiv: dividend == " << dividend << '\n'); DEBUG(dbgs() << "KnuthDiv: dividend == " << dividend << '\n');
uint64_t qp = dividend / v[n-1]; uint64_t qp = dividend / v[n-1];
uint64_t rp = dividend % v[n-1]; uint64_t rp = dividend % v[n-1];
@ -1329,14 +1329,14 @@ static void KnuthDiv(uint32_t *u, uint32_t *v, uint32_t *q, uint32_t* r,
int64_t borrow = 0; int64_t borrow = 0;
for (unsigned i = 0; i < n; ++i) { for (unsigned i = 0; i < n; ++i) {
uint64_t p = uint64_t(qp) * uint64_t(v[i]); uint64_t p = uint64_t(qp) * uint64_t(v[i]);
int64_t subres = int64_t(u[j+i]) - borrow - (unsigned)p; int64_t subres = int64_t(u[j+i]) - borrow - Lo_32(p);
u[j+i] = (unsigned)subres; u[j+i] = Lo_32(subres);
borrow = (p >> 32) - (subres >> 32); borrow = Hi_32(p) - Hi_32(subres);
DEBUG(dbgs() << "KnuthDiv: u[j+i] = " << u[j+i] DEBUG(dbgs() << "KnuthDiv: u[j+i] = " << u[j+i]
<< ", borrow = " << borrow << '\n'); << ", borrow = " << borrow << '\n');
} }
bool isNeg = u[j+n] < borrow; bool isNeg = u[j+n] < borrow;
u[j+n] -= (unsigned)borrow; u[j+n] -= Lo_32(borrow);
DEBUG(dbgs() << "KnuthDiv: after subtraction:"); DEBUG(dbgs() << "KnuthDiv: after subtraction:");
DEBUG(for (int i = m+n; i >=0; i--) dbgs() << " " << u[i]); DEBUG(for (int i = m+n; i >=0; i--) dbgs() << " " << u[i]);
@ -1344,7 +1344,7 @@ static void KnuthDiv(uint32_t *u, uint32_t *v, uint32_t *q, uint32_t* r,
// D5. [Test remainder.] Set q[j] = qp. If the result of step D4 was // D5. [Test remainder.] Set q[j] = qp. If the result of step D4 was
// negative, go to step D6; otherwise go on to step D7. // negative, go to step D6; otherwise go on to step D7.
q[j] = (unsigned)qp; q[j] = Lo_32(qp);
if (isNeg) { if (isNeg) {
// D6. [Add back]. The probability that this step is necessary is very // D6. [Add back]. The probability that this step is necessary is very
// small, on the order of only 2/b. Make sure that test data accounts for // small, on the order of only 2/b. Make sure that test data accounts for