From 3822ff5c71478c7c90a50ca57045fb676fcb5005 Mon Sep 17 00:00:00 2001 From: Reid Spencer Date: Wed, 8 Nov 2006 06:47:33 +0000 Subject: For PR950: This patch converts the old SHR instruction into two instructions, AShr (Arithmetic) and LShr (Logical). The Shr instructions now are not dependent on the sign of their operands. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31542 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Bytecode/Reader/Reader.cpp | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'lib/Bytecode/Reader/Reader.cpp') diff --git a/lib/Bytecode/Reader/Reader.cpp b/lib/Bytecode/Reader/Reader.cpp index c20eeddcbf..ec74f78e7a 100644 --- a/lib/Bytecode/Reader/Reader.cpp +++ b/lib/Bytecode/Reader/Reader.cpp @@ -719,7 +719,15 @@ BytecodeReader::handleObsoleteOpcodes( Opcode = Instruction::Shl; break; case 31: // Shr - Opcode = Instruction::Shr; + // The type of the instruction is based on the operands. We need to + // select ashr or lshr based on that type. The iType values are hardcoded + // to the values used in bytecode version 5 (and prior) because it is + // likely these codes will change in future versions of LLVM. This if + // statement says "if (integer type and signed)" + if (iType >= 2 && iType <= 9 && iType % 2 != 0) + Opcode = Instruction::AShr; + else + Opcode = Instruction::LShr; break; case 32: { //VANext_old ( <= llvm 1.5 ) const Type* ArgTy = getValue(iType, Oprnds[0])->getType(); @@ -987,7 +995,8 @@ void BytecodeReader::ParseInstruction(std::vector &Oprnds, } case Instruction::Shl: - case Instruction::Shr: + case Instruction::LShr: + case Instruction::AShr: Result = new ShiftInst(Instruction::OtherOps(Opcode), getValue(iType, Oprnds[0]), getValue(Type::UByteTyID, Oprnds[1])); @@ -1707,7 +1716,10 @@ inline unsigned fixCEOpcodes( Opcode = Instruction::Shl; break; case 31: // Shr - Opcode = Instruction::Shr; + if (ArgVec[0]->getType()->isSigned()) + Opcode = Instruction::AShr; + else + Opcode = Instruction::LShr; break; case 34: // Select Opcode = Instruction::Select; -- cgit v1.2.3-18-g5258