diff options
Diffstat (limited to 'llvm/lib/CodeGen')
| -rw-r--r-- | llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp b/llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp index aef43568b63..31e28f5ed5c 100644 --- a/llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp +++ b/llvm/lib/CodeGen/GlobalISel/GISelKnownBits.cpp @@ -131,6 +131,19 @@ void GISelKnownBits::computeKnownBitsImpl(Register R, KnownBits &Known, Known.Zero.setLowBits(KnownZeroLow); break; } + case TargetOpcode::G_XOR: { + computeKnownBitsImpl(MI.getOperand(2).getReg(), Known, DemandedElts, + Depth + 1); + computeKnownBitsImpl(MI.getOperand(1).getReg(), Known2, DemandedElts, + Depth + 1); + + // Output known-0 bits are known if clear or set in both the LHS & RHS. + APInt KnownZeroOut = (Known.Zero & Known2.Zero) | (Known.One & Known2.One); + // Output known-1 are known to be set if set in only one of the LHS, RHS. + Known.One = (Known.Zero & Known2.One) | (Known.One & Known2.Zero); + Known.Zero = KnownZeroOut; + break; + } // G_GEP is like G_ADD. FIXME: Is this true for all targets? case TargetOpcode::G_GEP: case TargetOpcode::G_ADD: { |
