Fix a really subtle and obnoxious memory bug that caused issues with an

llvm-gcc4 boostrap.  Whenever a node is deleted by the dag combiner, it
*must* be returned by the visit function, or the dag combiner will not
know that the node has been processed (and will, e.g., send it to the
target dag combine xforms).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27922 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2006-04-20 23:55:59 +00:00
parent 44fa691873
commit fedced7bc3

View File

@ -1080,7 +1080,7 @@ SDOperand DAGCombiner::visitAND(SDNode *N) {
// zero_extend, to avoid duplicating things. This will later cause this
// AND to be folded.
CombineTo(N0.Val, Zext);
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
}
// fold (and (setcc x), (setcc y)) -> (setcc (and x, y))
@ -1157,7 +1157,7 @@ SDOperand DAGCombiner::visitAND(SDNode *N) {
EVT);
AddToWorkList(N);
CombineTo(N0.Val, ExtLoad, ExtLoad.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
}
// fold (zext_inreg (sextload x)) -> (zextload x) iff load has one use
@ -1172,7 +1172,7 @@ SDOperand DAGCombiner::visitAND(SDNode *N) {
EVT);
AddToWorkList(N);
CombineTo(N0.Val, ExtLoad, ExtLoad.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
}
@ -1212,7 +1212,7 @@ SDOperand DAGCombiner::visitAND(SDNode *N) {
N0.getOperand(2), EVT);
AddToWorkList(N);
CombineTo(N0.Val, Load, Load.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
}
@ -1797,7 +1797,7 @@ SDOperand DAGCombiner::visitSIGN_EXTEND(SDNode *N) {
CombineTo(N, ExtLoad);
CombineTo(N0.Val, DAG.getNode(ISD::TRUNCATE, N0.getValueType(), ExtLoad),
ExtLoad.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
// fold (sext (sextload x)) -> (sext (truncate (sextload x)))
@ -1810,7 +1810,7 @@ SDOperand DAGCombiner::visitSIGN_EXTEND(SDNode *N) {
CombineTo(N, ExtLoad);
CombineTo(N0.Val, DAG.getNode(ISD::TRUNCATE, N0.getValueType(), ExtLoad),
ExtLoad.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
return SDOperand();
@ -1840,7 +1840,7 @@ SDOperand DAGCombiner::visitZERO_EXTEND(SDNode *N) {
CombineTo(N, ExtLoad);
CombineTo(N0.Val, DAG.getNode(ISD::TRUNCATE, N0.getValueType(), ExtLoad),
ExtLoad.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
// fold (zext (zextload x)) -> (zext (truncate (zextload x)))
@ -1853,7 +1853,7 @@ SDOperand DAGCombiner::visitZERO_EXTEND(SDNode *N) {
CombineTo(N, ExtLoad);
CombineTo(N0.Val, DAG.getNode(ISD::TRUNCATE, N0.getValueType(), ExtLoad),
ExtLoad.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
return SDOperand();
}
@ -1915,7 +1915,7 @@ SDOperand DAGCombiner::visitSIGN_EXTEND_INREG(SDNode *N) {
EVT);
CombineTo(N, ExtLoad);
CombineTo(N0.Val, ExtLoad, ExtLoad.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
// fold (sext_inreg (zextload x)) -> (sextload x) iff load has one use
if (N0.getOpcode() == ISD::ZEXTLOAD && N0.hasOneUse() &&
@ -1926,7 +1926,7 @@ SDOperand DAGCombiner::visitSIGN_EXTEND_INREG(SDNode *N) {
EVT);
CombineTo(N, ExtLoad);
CombineTo(N0.Val, ExtLoad, ExtLoad.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
return SDOperand();
}
@ -1975,7 +1975,7 @@ SDOperand DAGCombiner::visitTRUNCATE(SDNode *N) {
SDOperand Load = DAG.getLoad(VT, N0.getOperand(0), NewPtr,N0.getOperand(2));
AddToWorkList(N);
CombineTo(N0.Val, Load, Load.getValue(1));
return SDOperand();
return SDOperand(N, 0); // Return N so it doesn't get rechecked!
}
return SDOperand();
}