diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/TargetLowering.cpp')
-rw-r--r-- | lib/CodeGen/SelectionDAG/TargetLowering.cpp | 103 |
1 files changed, 2 insertions, 101 deletions
diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp index 4de6e35b2e..6974dde6f6 100644 --- a/lib/CodeGen/SelectionDAG/TargetLowering.cpp +++ b/lib/CodeGen/SelectionDAG/TargetLowering.cpp @@ -2434,105 +2434,6 @@ bool TargetLowering::isLegalAddressingMode(const AddrMode &AM, return true; } -struct mu { - APInt m; // magic number - bool a; // add indicator - unsigned s; // shift amount -}; - -/// magicu - calculate the magic numbers required to codegen an integer udiv as -/// a sequence of multiply, add and shifts. Requires that the divisor not be 0. -static mu magicu(const APInt& d) { - unsigned p; - APInt nc, delta, q1, r1, q2, r2; - struct mu magu; - magu.a = 0; // initialize "add" indicator - APInt allOnes = APInt::getAllOnesValue(d.getBitWidth()); - APInt signedMin = APInt::getSignedMinValue(d.getBitWidth()); - APInt signedMax = APInt::getSignedMaxValue(d.getBitWidth()); - - nc = allOnes - (-d).urem(d); - p = d.getBitWidth() - 1; // initialize p - q1 = signedMin.udiv(nc); // initialize q1 = 2p/nc - r1 = signedMin - q1*nc; // initialize r1 = rem(2p,nc) - q2 = signedMax.udiv(d); // initialize q2 = (2p-1)/d - r2 = signedMax - q2*d; // initialize r2 = rem((2p-1),d) - do { - p = p + 1; - if (r1.uge(nc - r1)) { - q1 = q1 + q1 + 1; // update q1 - r1 = r1 + r1 - nc; // update r1 - } - else { - q1 = q1+q1; // update q1 - r1 = r1+r1; // update r1 - } - if ((r2 + 1).uge(d - r2)) { - if (q2.uge(signedMax)) magu.a = 1; - q2 = q2+q2 + 1; // update q2 - r2 = r2+r2 + 1 - d; // update r2 - } - else { - if (q2.uge(signedMin)) magu.a = 1; - q2 = q2+q2; // update q2 - r2 = r2+r2 + 1; // update r2 - } - delta = d - 1 - r2; - } while (p < d.getBitWidth()*2 && - (q1.ult(delta) || (q1 == delta && r1 == 0))); - magu.m = q2 + 1; // resulting magic number - magu.s = p - d.getBitWidth(); // resulting shift - return magu; -} - -// Magic for divide replacement -struct ms { - APInt m; // magic number - unsigned s; // shift amount -}; - -/// magic - calculate the magic numbers required to codegen an integer sdiv as -/// a sequence of multiply and shifts. Requires that the divisor not be 0, 1, -/// or -1. -static ms magic(const APInt& d) { - unsigned p; - APInt ad, anc, delta, q1, r1, q2, r2, t; - APInt allOnes = APInt::getAllOnesValue(d.getBitWidth()); - APInt signedMin = APInt::getSignedMinValue(d.getBitWidth()); - APInt signedMax = APInt::getSignedMaxValue(d.getBitWidth()); - struct ms mag; - - ad = d.abs(); - t = signedMin + (d.lshr(d.getBitWidth() - 1)); - anc = t - 1 - t.urem(ad); // absolute value of nc - p = d.getBitWidth() - 1; // initialize p - q1 = signedMin.udiv(anc); // initialize q1 = 2p/abs(nc) - r1 = signedMin - q1*anc; // initialize r1 = rem(2p,abs(nc)) - q2 = signedMin.udiv(ad); // initialize q2 = 2p/abs(d) - r2 = signedMin - q2*ad; // initialize r2 = rem(2p,abs(d)) - do { - p = p + 1; - q1 = q1<<1; // update q1 = 2p/abs(nc) - r1 = r1<<1; // update r1 = rem(2p/abs(nc)) - if (r1.uge(anc)) { // must be unsigned comparison - q1 = q1 + 1; - r1 = r1 - anc; - } - q2 = q2<<1; // update q2 = 2p/abs(d) - r2 = r2<<1; // update r2 = rem(2p/abs(d)) - if (r2.uge(ad)) { // must be unsigned comparison - q2 = q2 + 1; - r2 = r2 - ad; - } - delta = ad - r2; - } while (q1.ule(delta) || (q1 == delta && r1 == 0)); - - mag.m = q2 + 1; - if (d.isNegative()) mag.m = -mag.m; // resulting magic number - mag.s = p - d.getBitWidth(); // resulting shift - return mag; -} - /// BuildSDIVSequence - Given an ISD::SDIV node expressing a divide by constant, /// return a DAG expression to select that will generate the same value by /// multiplying by a magic number. See: @@ -2548,7 +2449,7 @@ SDValue TargetLowering::BuildSDIV(SDNode *N, SelectionDAG &DAG, return SDValue(); APInt d = cast<ConstantSDNode>(N->getOperand(1))->getAPIntValue(); - ms magics = magic(d); + APInt::ms magics = d.magic(); // Multiply the numerator (operand 0) by the magic value // FIXME: We should support doing a MUL in a wider type @@ -2607,7 +2508,7 @@ SDValue TargetLowering::BuildUDIV(SDNode *N, SelectionDAG &DAG, // FIXME: We should use a narrower constant when the upper // bits are known to be zero. ConstantSDNode *N1C = cast<ConstantSDNode>(N->getOperand(1)); - mu magics = magicu(N1C->getAPIntValue()); + APInt::mu magics = N1C->getAPIntValue().magicu(); // Multiply the numerator (operand 0) by the magic value // FIXME: We should support doing a MUL in a wider type |