From 6eae520de934f6e3aa60e976e3efa37fa7a39a72 Mon Sep 17 00:00:00 2001 From: Bob Wilson Date: Fri, 11 Jun 2010 21:34:50 +0000 Subject: Add instruction encoding for the Neon VMOV immediate instruction. This changes the machine instruction representation of the immediate value to be encoded into an integer with similar fields as the actual VMOV instruction. This makes things easier for the disassembler, since it can just stuff the bits into the immediate operand, but harder for the asm printer since it has to decode the value to be printed. Testcase for the encoding will follow later when MC has more support for ARM. llvm-svn: 105836 --- llvm/lib/Target/ARM/AsmPrinter/ARMInstPrinter.cpp | 50 +++++++++++++++-------- 1 file changed, 32 insertions(+), 18 deletions(-) (limited to 'llvm/lib/Target/ARM/AsmPrinter/ARMInstPrinter.cpp') diff --git a/llvm/lib/Target/ARM/AsmPrinter/ARMInstPrinter.cpp b/llvm/lib/Target/ARM/AsmPrinter/ARMInstPrinter.cpp index 2b94b76087e..b59852ebfcb 100644 --- a/llvm/lib/Target/ARM/AsmPrinter/ARMInstPrinter.cpp +++ b/llvm/lib/Target/ARM/AsmPrinter/ARMInstPrinter.cpp @@ -779,22 +779,36 @@ void ARMInstPrinter::printVFPf64ImmOperand(const MCInst *MI, unsigned OpNum, O << '#' << MI->getOperand(OpNum).getImm(); } -void ARMInstPrinter::printHex8ImmOperand(const MCInst *MI, unsigned OpNum, - raw_ostream &O) { - O << "#0x" << utohexstr(MI->getOperand(OpNum).getImm() & 0xff); -} - -void ARMInstPrinter::printHex16ImmOperand(const MCInst *MI, unsigned OpNum, - raw_ostream &O) { - O << "#0x" << utohexstr(MI->getOperand(OpNum).getImm() & 0xffff); -} - -void ARMInstPrinter::printHex32ImmOperand(const MCInst *MI, unsigned OpNum, - raw_ostream &O) { - O << "#0x" << utohexstr(MI->getOperand(OpNum).getImm() & 0xffffffff); -} - -void ARMInstPrinter::printHex64ImmOperand(const MCInst *MI, unsigned OpNum, - raw_ostream &O) { - O << "#0x" << utohexstr(MI->getOperand(OpNum).getImm()); +void ARMInstPrinter::printNEONModImmOperand(const MCInst *MI, unsigned OpNum, + raw_ostream &O) { + unsigned Imm = MI->getOperand(OpNum).getImm(); + unsigned OpCmode = (Imm >> 8) & 0x1f; + unsigned Imm8 = Imm & 0xff; + uint64_t Val = 0; + + if (OpCmode == 0xe) { + // 8-bit vector elements + Val = Imm8; + } else if ((OpCmode & 0xc) == 0x8) { + // 16-bit vector elements + unsigned ByteNum = (OpCmode & 0x6) >> 1; + Val = Imm8 << (8 * ByteNum); + } else if ((OpCmode & 0x8) == 0) { + // 32-bit vector elements, zero with one byte set + unsigned ByteNum = (OpCmode & 0x6) >> 1; + Val = Imm8 << (8 * ByteNum); + } else if ((OpCmode & 0xe) == 0xc) { + // 32-bit vector elements, one byte with low bits set + unsigned ByteNum = (OpCmode & 0x1); + Val = (Imm8 << (8 * ByteNum)) | (0xffff >> (8 * (1 - ByteNum))); + } else if (OpCmode == 0x1e) { + // 64-bit vector elements + for (unsigned ByteNum = 0; ByteNum < 8; ++ByteNum) { + if ((Imm >> ByteNum) & 1) + Val |= (uint64_t)0xff << (8 * ByteNum); + } + } else { + assert(false && "Unsupported NEON immediate"); + } + O << "#0x" << utohexstr(Val); } -- cgit v1.2.3