diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Target/X86/X86ISelLowering.cpp | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index c55a1ef..1d72aad 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -3059,6 +3059,50 @@ static unsigned TranslateX86CC(ISD::CondCode SetCCOpcode, bool isFP, RHS = DAG.getConstant(0, RHS.getValueType()); return X86::COND_LE; } + if (SetCCOpcode == ISD::SETULT || SetCCOpcode == ISD::SETUGE) { + unsigned TrailZeros = RHSC->getAPIntValue().countTrailingZeros(); + if (TrailZeros >= 32) { + // The constant doesn't fit in cmp immediate field. Right shift LHS by + // the # of trailing zeros and truncate it to 32-bit. Then compare + // against shifted RHS. + assert(LHS.getValueType() == MVT::i64 && "Expecting a 64-bit cmp!"); + DebugLoc dl = LHS.getDebugLoc(); + LHS = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, + DAG.getNode(ISD::SRL, dl, MVT::i64, LHS, + DAG.getConstant(TrailZeros, MVT::i8))); + uint64_t C = RHSC->getZExtValue() >> TrailZeros; + + if (SetCCOpcode == ISD::SETULT) { + // X < 0x300000000 -> (X >> 32) < 3 + // X < 0x100000000 -> (X >> 32) == 0 + // X < 0x200000000 -> (X >> 33) == 0 + if (C == 1) { + RHS = DAG.getConstant(0, MVT::i32); + return X86::COND_E; + } + RHS = DAG.getConstant(C, MVT::i32); + return X86::COND_B; + } else /* SetCCOpcode == ISD::SETUGE */ { + // X >= 0x100000000 -> (X >> 32) >= 1 + RHS = DAG.getConstant(C, MVT::i32); + return X86::COND_AE; + } + } + } + if (SetCCOpcode == ISD::SETUGT) { + unsigned TrailOnes = RHSC->getAPIntValue().countTrailingOnes(); + if (TrailOnes >= 32 && !RHSC->isAllOnesValue()) { + assert(LHS.getValueType() == MVT::i64 && "Expecting a 64-bit cmp!"); + DebugLoc dl = LHS.getDebugLoc(); + LHS = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, + DAG.getNode(ISD::SRL, dl, MVT::i64, LHS, + DAG.getConstant(TrailOnes, MVT::i8))); + uint64_t C = (RHSC->getZExtValue()+1) >> TrailOnes; + // X > 0x0ffffffff -> (X >> 32) >= 1 + RHS = DAG.getConstant(C, MVT::i32); + return X86::COND_AE; + } + } } switch (SetCCOpcode) { |