LiveRegMatrix: Fix some subreg interference checks
Surprisingly, one of the three interference checks in LiveRegMatrix was
using the main live range instead of the apropriate subregister range
resulting in unnecessarily conservative results.
llvm-svn: 296722
diff --git a/llvm/lib/CodeGen/LiveRegMatrix.cpp b/llvm/lib/CodeGen/LiveRegMatrix.cpp
index 596d787..882de1a 100644
--- a/llvm/lib/CodeGen/LiveRegMatrix.cpp
+++ b/llvm/lib/CodeGen/LiveRegMatrix.cpp
@@ -175,10 +175,10 @@
return Result;
}
-LiveIntervalUnion::Query &LiveRegMatrix::query(LiveInterval &VirtReg,
+LiveIntervalUnion::Query &LiveRegMatrix::query(const LiveRange &LR,
unsigned RegUnit) {
LiveIntervalUnion::Query &Q = Queries[RegUnit];
- Q.init(UserTag, VirtReg, Matrix[RegUnit]);
+ Q.init(UserTag, LR, Matrix[RegUnit]);
return Q;
}
@@ -196,9 +196,12 @@
return IK_RegUnit;
// Check the matrix for virtual register interference.
- for (MCRegUnitIterator Units(PhysReg, TRI); Units.isValid(); ++Units)
- if (query(VirtReg, *Units).checkInterference())
- return IK_VirtReg;
+ bool Interference = foreachUnit(TRI, VirtReg, PhysReg,
+ [&](unsigned Unit, const LiveRange &LR) {
+ return query(LR, Unit).checkInterference();
+ });
+ if (Interference)
+ return IK_VirtReg;
return IK_Free;
}