From d894f1d274515db527962b6db2d9983827fdcbd6 Mon Sep 17 00:00:00 2001 From: Owen Anderson Date: Mon, 25 Aug 2008 21:32:34 +0000 Subject: [PATCH] Expand bitcast support in fast isel to support bitcasts of non-constant values by emitting reg-reg copies. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55340 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/FastISel.cpp | 30 ++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp index c8c219d39d4..c48a2f2c621 100644 --- a/lib/CodeGen/SelectionDAG/FastISel.cpp +++ b/lib/CodeGen/SelectionDAG/FastISel.cpp @@ -234,8 +234,36 @@ FastISel::SelectInstructions(BasicBlock::iterator Begin, } else // TODO: Support vector and fp constants. return I; + } else if (!isa(I->getOperand(0))) { + // Bitcasts of non-constant values become reg-reg copies. + MVT SrcVT = MVT::getMVT(I->getOperand(0)->getType()); + MVT DstVT = MVT::getMVT(I->getOperand(0)->getType()); + + if (SrcVT == MVT::Other || !SrcVT.isSimple() || + DstVT == MVT::Other || !DstVT.isSimple() || + !TLI.isTypeLegal(SrcVT) || !TLI.isTypeLegal(DstVT)) + // Unhandled type. Halt "fast" selection and bail. + return I; + if (!TLI.isConvertLegal(SrcVT, DstVT)) + // Illegal conversion. Halt "fast" selection and bail. + return I: + + // Otherwise, insert a register-to-register copy. + TargetRegisterClass* SrcClass = TLI.getRegClassFor(SrcVT); + TargetRegisterClass* DstClass = TLI.getRegClassFor(DstVT); + unsigned Op0 = ValueMap[I->getOperand(0)]; + unsigned ResultReg = createResultReg(DstClass); + + if (Op0 == 0) + // Unhandled operand. Halt "fast" selection and bail. + return false; + + TII.copyRegToReg(*MBB, MBB->end(), ResultReg, Op0, DstClass, SrcClass); + ValueMap[I] = ResultReg; + + break; } else - // TODO: Support non-constant bitcasts. + // Casting a non-integral constant? return I; default: