[llvm-commits] CVS: llvm/lib/Target/Alpha/AlphaISelLowering.cpp
Andrew Lenharth
alenhar2 at cs.uiuc.edu
Tue May 16 10:42:31 PDT 2006
Changes in directory llvm/lib/Target/Alpha:
AlphaISelLowering.cpp updated: 1.48 -> 1.49
---
Log message:
Move this code to a common place
---
Diffs of the changes: (+4 -148)
AlphaISelLowering.cpp | 152 +-------------------------------------------------
1 files changed, 4 insertions(+), 148 deletions(-)
Index: llvm/lib/Target/Alpha/AlphaISelLowering.cpp
diff -u llvm/lib/Target/Alpha/AlphaISelLowering.cpp:1.48 llvm/lib/Target/Alpha/AlphaISelLowering.cpp:1.49
--- llvm/lib/Target/Alpha/AlphaISelLowering.cpp:1.48 Fri May 12 13:17:25 2006
+++ llvm/lib/Target/Alpha/AlphaISelLowering.cpp Tue May 16 12:42:15 2006
@@ -25,151 +25,6 @@
#include <iostream>
using namespace llvm;
-//Shamelessly adapted from PPC32
-// Structure used to return the necessary information to codegen an SDIV as
-// a multiply.
-struct ms {
- int64_t m; // magic number
- int64_t s; // shift amount
-};
-
-struct mu {
- uint64_t m; // magic number
- int64_t a; // add indicator
- int64_t 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 struct ms magic(int64_t d) {
- int64_t p;
- uint64_t ad, anc, delta, q1, r1, q2, r2, t;
- const uint64_t two63 = 9223372036854775808ULL; // 2^63
- struct ms mag;
-
- ad = llabs(d);
- t = two63 + ((uint64_t)d >> 63);
- anc = t - 1 - t%ad; // absolute value of nc
- p = 63; // initialize p
- q1 = two63/anc; // initialize q1 = 2p/abs(nc)
- r1 = two63 - q1*anc; // initialize r1 = rem(2p,abs(nc))
- q2 = two63/ad; // initialize q2 = 2p/abs(d)
- r2 = two63 - q2*ad; // initialize r2 = rem(2p,abs(d))
- do {
- p = p + 1;
- q1 = 2*q1; // update q1 = 2p/abs(nc)
- r1 = 2*r1; // update r1 = rem(2p/abs(nc))
- if (r1 >= anc) { // must be unsigned comparison
- q1 = q1 + 1;
- r1 = r1 - anc;
- }
- q2 = 2*q2; // update q2 = 2p/abs(d)
- r2 = 2*r2; // update r2 = rem(2p/abs(d))
- if (r2 >= ad) { // must be unsigned comparison
- q2 = q2 + 1;
- r2 = r2 - ad;
- }
- delta = ad - r2;
- } while (q1 < delta || (q1 == delta && r1 == 0));
-
- mag.m = q2 + 1;
- if (d < 0) mag.m = -mag.m; // resulting magic number
- mag.s = p - 64; // resulting shift
- return mag;
-}
-
-/// 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 struct mu magicu(uint64_t d)
-{
- int64_t p;
- uint64_t nc, delta, q1, r1, q2, r2;
- struct mu magu;
- magu.a = 0; // initialize "add" indicator
- nc = - 1 - (-d)%d;
- p = 63; // initialize p
- q1 = 0x8000000000000000ull/nc; // initialize q1 = 2p/nc
- r1 = 0x8000000000000000ull - q1*nc; // initialize r1 = rem(2p,nc)
- q2 = 0x7FFFFFFFFFFFFFFFull/d; // initialize q2 = (2p-1)/d
- r2 = 0x7FFFFFFFFFFFFFFFull - q2*d; // initialize r2 = rem((2p-1),d)
- do {
- p = p + 1;
- if (r1 >= nc - r1 ) {
- q1 = 2*q1 + 1; // update q1
- r1 = 2*r1 - nc; // update r1
- }
- else {
- q1 = 2*q1; // update q1
- r1 = 2*r1; // update r1
- }
- if (r2 + 1 >= d - r2) {
- if (q2 >= 0x7FFFFFFFFFFFFFFFull) magu.a = 1;
- q2 = 2*q2 + 1; // update q2
- r2 = 2*r2 + 1 - d; // update r2
- }
- else {
- if (q2 >= 0x8000000000000000ull) magu.a = 1;
- q2 = 2*q2; // update q2
- r2 = 2*r2 + 1; // update r2
- }
- delta = d - 1 - r2;
- } while (p < 64 && (q1 < delta || (q1 == delta && r1 == 0)));
- magu.m = q2 + 1; // resulting magic number
- magu.s = p - 64; // resulting shift
- return magu;
-}
-
-/// 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:
-/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
-static SDOperand BuildSDIVSequence(SDOperand N, SelectionDAG* ISelDAG) {
- int64_t d = (int64_t)cast<ConstantSDNode>(N.getOperand(1))->getSignExtended();
- ms magics = magic(d);
- // Multiply the numerator (operand 0) by the magic value
- SDOperand Q = ISelDAG->getNode(ISD::MULHS, MVT::i64, N.getOperand(0),
- ISelDAG->getConstant(magics.m, MVT::i64));
- // If d > 0 and m < 0, add the numerator
- if (d > 0 && magics.m < 0)
- Q = ISelDAG->getNode(ISD::ADD, MVT::i64, Q, N.getOperand(0));
- // If d < 0 and m > 0, subtract the numerator.
- if (d < 0 && magics.m > 0)
- Q = ISelDAG->getNode(ISD::SUB, MVT::i64, Q, N.getOperand(0));
- // Shift right algebraic if shift value is nonzero
- if (magics.s > 0)
- Q = ISelDAG->getNode(ISD::SRA, MVT::i64, Q,
- ISelDAG->getConstant(magics.s, MVT::i64));
- // Extract the sign bit and add it to the quotient
- SDOperand T =
- ISelDAG->getNode(ISD::SRL, MVT::i64, Q, ISelDAG->getConstant(63, MVT::i64));
- return ISelDAG->getNode(ISD::ADD, MVT::i64, Q, T);
-}
-
-/// BuildUDIVSequence - Given an ISD::UDIV 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:
-/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
-static SDOperand BuildUDIVSequence(SDOperand N, SelectionDAG* ISelDAG) {
- unsigned d =
- (unsigned)cast<ConstantSDNode>(N.getOperand(1))->getSignExtended();
- mu magics = magicu(d);
- // Multiply the numerator (operand 0) by the magic value
- SDOperand Q = ISelDAG->getNode(ISD::MULHU, MVT::i64, N.getOperand(0),
- ISelDAG->getConstant(magics.m, MVT::i64));
- if (magics.a == 0) {
- Q = ISelDAG->getNode(ISD::SRL, MVT::i64, Q,
- ISelDAG->getConstant(magics.s, MVT::i64));
- } else {
- SDOperand NPQ = ISelDAG->getNode(ISD::SUB, MVT::i64, N.getOperand(0), Q);
- NPQ = ISelDAG->getNode(ISD::SRL, MVT::i64, NPQ,
- ISelDAG->getConstant(1, MVT::i64));
- NPQ = ISelDAG->getNode(ISD::ADD, MVT::i64, NPQ, Q);
- Q = ISelDAG->getNode(ISD::SRL, MVT::i64, NPQ,
- ISelDAG->getConstant(magics.s-1, MVT::i64));
- }
- return Q;
-}
/// AddLiveIn - This helper function adds the specified physical register to the
/// MachineFunction as a live in value. It also creates a corresponding virtual
@@ -593,8 +448,8 @@
MVT::ValueType VT = Op.Val->getValueType(0);
unsigned Opc = Op.Val->getOpcode() == ISD::UREM ? ISD::UDIV : ISD::SDIV;
SDOperand Tmp1 = Op.Val->getOpcode() == ISD::UREM ?
- BuildUDIVSequence(Op, &DAG) :
- BuildSDIVSequence(Op, &DAG);
+ BuildUDIV(Op.Val, DAG, NULL) :
+ BuildSDIV(Op.Val, DAG, NULL);
Tmp1 = DAG.getNode(ISD::MUL, VT, Tmp1, Op.getOperand(1));
Tmp1 = DAG.getNode(ISD::SUB, VT, Op.getOperand(0), Tmp1);
return Tmp1;
@@ -604,7 +459,8 @@
case ISD::UDIV:
if (MVT::isInteger(Op.getValueType())) {
if (Op.getOperand(1).getOpcode() == ISD::Constant)
- return Op.getOpcode() == ISD::SDIV ? BuildSDIVSequence(Op, &DAG) : BuildUDIVSequence(Op, &DAG);
+ return Op.getOpcode() == ISD::SDIV ? BuildSDIV(Op.Val, DAG, NULL)
+ : BuildUDIV(Op.Val, DAG, NULL);
const char* opstr = 0;
switch(Op.getOpcode()) {
case ISD::UREM: opstr = "__remqu"; break;
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