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Differential D38122

[DAGCombiner] Remove duplicate code from visitZERO_EXTEND
ClosedPublic

Authored by craig.topper on Sep 21 2017, 12:07 AM.

Details

Reviewers
RKSimon
spatel
arsenm
Commits
rG280f1337736b: [DAGCombiner] Remove duplicate code from visitZERO_EXTEND
rL313891: [DAGCombiner] Remove duplicate code from visitZERO_EXTEND
Summary

This exact block of code exists right below.

Diff Detail

Repository
rL LLVM

Event Timeline

craig.topper created this revision.Sep 21 2017, 12:07 AM
Herald added a subscriber: wdng. · View Herald TranscriptSep 21 2017, 12:07 AM
RKSimon accepted this revision.Sep 21 2017, 1:50 AM

LGTM

This revision is now accepted and ready to land.Sep 21 2017, 1:50 AM
Closed by commit rL313891: [DAGCombiner] Remove duplicate code from visitZERO_EXTEND (authored by ctopper). · Explain WhySep 21 2017, 10:31 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
llvm/
trunk/
lib/
CodeGen/
SelectionDAG/
14 lines

Diff 116217

llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

  • This file is larger than 256 KB, so syntax highlighting is disabled by default.
Show First 20 Lines • Show All 7,552 Lines • ▼ Show 20 Lines APInt TruncatedBits =
APInt::getBitsSet(Op.getValueSizeInBits(), APInt::getBitsSet(Op.getValueSizeInBits(),
N0.getValueSizeInBits(), N0.getValueSizeInBits(),
std::min(Op.getValueSizeInBits(), std::min(Op.getValueSizeInBits(),
VT.getSizeInBits())); VT.getSizeInBits()));
if (TruncatedBits.isSubsetOf(Known.Zero)) if (TruncatedBits.isSubsetOf(Known.Zero))
return DAG.getZExtOrTrunc(Op, SDLoc(N), VT); return DAG.getZExtOrTrunc(Op, SDLoc(N), VT);
} }
// fold (zext (truncate (load x))) -> (zext (smaller load x))
// fold (zext (truncate (srl (load x), c))) -> (zext (small load (x+c/n)))
if (N0.getOpcode() == ISD::TRUNCATE) {
if (SDValue NarrowLoad = ReduceLoadWidth(N0.getNode())) {
SDNode *oye = N0.getOperand(0).getNode();
if (NarrowLoad.getNode() != N0.getNode()) {
CombineTo(N0.getNode(), NarrowLoad);
// CombineTo deleted the truncate, if needed, but not what's under it.
AddToWorklist(oye);
}
return SDValue(N, 0); // Return N so it doesn't get rechecked!
}
}
// fold (zext (truncate x)) -> (and x, mask) // fold (zext (truncate x)) -> (and x, mask)
if (N0.getOpcode() == ISD::TRUNCATE) { if (N0.getOpcode() == ISD::TRUNCATE) {
// fold (zext (truncate (load x))) -> (zext (smaller load x)) // fold (zext (truncate (load x))) -> (zext (smaller load x))
// fold (zext (truncate (srl (load x), c))) -> (zext (smaller load (x+c/n))) // fold (zext (truncate (srl (load x), c))) -> (zext (smaller load (x+c/n)))
if (SDValue NarrowLoad = ReduceLoadWidth(N0.getNode())) { if (SDValue NarrowLoad = ReduceLoadWidth(N0.getNode())) {
SDNode *oye = N0.getOperand(0).getNode(); SDNode *oye = N0.getOperand(0).getNode();
if (NarrowLoad.getNode() != N0.getNode()) { if (NarrowLoad.getNode() != N0.getNode()) {
CombineTo(N0.getNode(), NarrowLoad); CombineTo(N0.getNode(), NarrowLoad);
▲ Show 20 Lines • Show All 9,915 Lines • Show Last 20 Lines