From ab20565a8298094a938ca11e13d64bed6443f90f Mon Sep 17 00:00:00 2001
From: Dan Gohman <dan433584@gmail.com>
Date: Sat, 11 Feb 2017 00:02:23 +0000
Subject: [PATCH] [WebAssembly] Remove old experimental disassemler code.

Remove support for disassembling an old experimental wasm binary format, which
is no longer in use anywhere.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294809 91177308-0d34-0410-b5e6-96231b3b80d8
---
 .../Disassembler/WebAssemblyDisassembler.cpp  | 86 +------------------
 1 file changed, 2 insertions(+), 84 deletions(-)

diff --git a/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp b/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp
index d5444b2a1d2..b5f53114d3e 100644
--- a/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp
+++ b/lib/Target/WebAssembly/Disassembler/WebAssemblyDisassembler.cpp
@@ -63,90 +63,8 @@ extern "C" void LLVMInitializeWebAssemblyDisassembler() {
 MCDisassembler::DecodeStatus WebAssemblyDisassembler::getInstruction(
     MCInst &MI, uint64_t &Size, ArrayRef<uint8_t> Bytes, uint64_t /*Address*/,
     raw_ostream &OS, raw_ostream &CS) const {
-  Size = 0;
-  uint64_t Pos = 0;
 
-  // Read the opcode.
-  if (Pos + sizeof(uint64_t) > Bytes.size())
-    return MCDisassembler::Fail;
-  uint64_t Opcode = support::endian::read64le(Bytes.data() + Pos);
-  Pos += sizeof(uint64_t);
+  // TODO: Implement disassembly.
 
-  if (Opcode >= WebAssembly::INSTRUCTION_LIST_END)
-    return MCDisassembler::Fail;
-
-  MI.setOpcode(Opcode);
-  const MCInstrDesc &Desc = MCII->get(Opcode);
-  unsigned NumFixedOperands = Desc.NumOperands;
-
-  // If it's variadic, read the number of extra operands.
-  unsigned NumExtraOperands = 0;
-  if (Desc.isVariadic()) {
-    if (Pos + sizeof(uint64_t) > Bytes.size())
-      return MCDisassembler::Fail;
-    NumExtraOperands = support::endian::read64le(Bytes.data() + Pos);
-    Pos += sizeof(uint64_t);
-  }
-
-  // Read the fixed operands. These are described by the MCInstrDesc.
-  for (unsigned i = 0; i < NumFixedOperands; ++i) {
-    const MCOperandInfo &Info = Desc.OpInfo[i];
-    switch (Info.OperandType) {
-    case MCOI::OPERAND_IMMEDIATE:
-    case WebAssembly::OPERAND_LOCAL:
-    case WebAssembly::OPERAND_GLOBAL:
-    case WebAssembly::OPERAND_P2ALIGN:
-    case WebAssembly::OPERAND_BASIC_BLOCK: {
-      if (Pos + sizeof(uint64_t) > Bytes.size())
-        return MCDisassembler::Fail;
-      uint64_t Imm = support::endian::read64le(Bytes.data() + Pos);
-      Pos += sizeof(uint64_t);
-      MI.addOperand(MCOperand::createImm(Imm));
-      break;
-    }
-    case MCOI::OPERAND_REGISTER: {
-      if (Pos + sizeof(uint64_t) > Bytes.size())
-        return MCDisassembler::Fail;
-      uint64_t Reg = support::endian::read64le(Bytes.data() + Pos);
-      Pos += sizeof(uint64_t);
-      MI.addOperand(MCOperand::createReg(Reg));
-      break;
-    }
-    case WebAssembly::OPERAND_F32IMM:
-    case WebAssembly::OPERAND_F64IMM: {
-      // TODO: MC converts all floating point immediate operands to double.
-      // This is fine for numeric values, but may cause NaNs to change bits.
-      if (Pos + sizeof(uint64_t) > Bytes.size())
-        return MCDisassembler::Fail;
-      uint64_t Bits = support::endian::read64le(Bytes.data() + Pos);
-      Pos += sizeof(uint64_t);
-      double Imm;
-      memcpy(&Imm, &Bits, sizeof(Imm));
-      MI.addOperand(MCOperand::createFPImm(Imm));
-      break;
-    }
-    default:
-      llvm_unreachable("unimplemented operand kind");
-    }
-  }
-
-  // Read the extra operands.
-  assert(NumExtraOperands == 0 || Desc.isVariadic());
-  for (unsigned i = 0; i < NumExtraOperands; ++i) {
-    if (Pos + sizeof(uint64_t) > Bytes.size())
-      return MCDisassembler::Fail;
-    if (Desc.TSFlags & WebAssemblyII::VariableOpIsImmediate) {
-      // Decode extra immediate operands.
-      uint64_t Imm = support::endian::read64le(Bytes.data() + Pos);
-      MI.addOperand(MCOperand::createImm(Imm));
-    } else {
-      // Decode extra register operands.
-      uint64_t Reg = support::endian::read64le(Bytes.data() + Pos);
-      MI.addOperand(MCOperand::createReg(Reg));
-    }
-    Pos += sizeof(uint64_t);
-  }
-
-  Size = Pos;
-  return MCDisassembler::Success;
+  return MCDisassembler::Fail;
 }
-- 
2.50.1