llvm-mc/AsmMatcher: Move to a slightly more sane matching design.

 - Still not very sane, but a least its not 60k lines on X86. :)

 - In terms of correctness, currently some things are hard wired for X86, and we
   still don't properly resolve ambiguities (this is ignoring the instructions
   we don't even match due to funny .td stuff or other corner cases).

The high level changes:
 1. Represent tokens which are significant for matching explicitly as separate
    operands. This uniformly handles not only the instruction mnemonic, but
    also 'signficiant' syntax like the '*' in "call * ...".

 2. Separate the matching of operands to an instruction from the construction of
    the MCInst. In theory this can be done during matching, but since the number
    of variations is small I think it makes sense to decompose the problems.

 3. Improved a few of the mechanisms to at least successfully flatten / tokenize
    the assembly strings for PowerPC and ARM.

 4. The comment at the top of AsmMatcherEmitter.cpp explains the approach I'm
    moving towards for handling ambiguous instructions. The high-bit is to infer
    a partial ordering of the operand classes (and force the user to specify one
    if we can't) and use that to resolve ambiguities.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78378 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 61 insertions, 139 deletions

diff --git a/lib/Target/X86/AsmParser/X86AsmParser.cpp b/lib/Target/X86/AsmParser/X86AsmParser.cpp
index 4d7358a..9d85f4d 100644
--- a/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -26,10 +26,6 @@ class X86ATTAsmParser : public TargetAsmParser {
   MCAsmParser &Parser;
 
 private:
-  bool MatchInstruction(const StringRef &Name,
-                        SmallVectorImpl<X86Operand> &Operands,
-                        MCInst &Inst);
-
   MCAsmParser &getParser() const { return Parser; }
 
   MCAsmLexer &getLexer() const { return Parser.getLexer(); }
@@ -47,6 +43,9 @@ private:
   /// @name Auto-generated Match Functions
   /// {  
 
+  bool MatchInstruction(SmallVectorImpl<X86Operand> &Operands,
+                        MCInst &Inst);
+
   bool MatchRegisterName(const StringRef &Name, unsigned &RegNo);
 
   /// }
@@ -67,6 +66,7 @@ namespace {
 /// instruction.
 struct X86Operand {
   enum {
+    Token,
     Register,
     Immediate,
     Memory
@@ -74,6 +74,11 @@ struct X86Operand {
 
   union {
     struct {
+      const char *Data;
+      unsigned Length;
+    } Tok;
+
+    struct {
       unsigned RegNo;
     } Reg;
 
@@ -90,6 +95,11 @@ struct X86Operand {
     } Mem;
   };
 
+  StringRef getToken() const {
+    assert(Kind == Token && "Invalid access!");
+    return StringRef(Tok.Data, Tok.Length);
+  }
+
   unsigned getReg() const {
     assert(Kind == Register && "Invalid access!");
     return Reg.RegNo;
@@ -121,18 +131,61 @@ struct X86Operand {
     return Mem.Scale;
   }
 
+  bool isToken(const StringRef &Str) const { 
+    return Kind == Token && Str == getToken(); 
+  }
+
+  bool isImm() const { return Kind == Immediate; }
+  
+  bool isMem() const { return Kind == Memory; }
+
+  bool isReg() const { return Kind == Register; }
+
+  void addRegOperands(MCInst &Inst, unsigned N) {
+    assert(N == 1 && "Invalid number of operands!");
+    Inst.addOperand(MCOperand::CreateReg(getReg()));
+  }
+
+  void addImmOperands(MCInst &Inst, unsigned N) {
+    assert(N == 1 && "Invalid number of operands!");
+    Inst.addOperand(MCOperand::CreateMCValue(getImm()));
+  }
+
+  void addMemOperands(MCInst &Inst, unsigned N) {
+    assert((N == 4 || N == 5) && "Invalid number of operands!");
+
+    Inst.addOperand(MCOperand::CreateReg(getMemBaseReg()));
+    Inst.addOperand(MCOperand::CreateImm(getMemScale()));
+    Inst.addOperand(MCOperand::CreateReg(getMemIndexReg()));
+    Inst.addOperand(MCOperand::CreateMCValue(getMemDisp()));
+
+    // FIXME: What a hack.
+    if (N == 5)
+      Inst.addOperand(MCOperand::CreateReg(getMemSegReg()));
+  }
+
+  static X86Operand CreateToken(StringRef Str) {
+    X86Operand Res;
+    Res.Kind = Token;
+    Res.Tok.Data = Str.data();
+    Res.Tok.Length = Str.size();
+    return Res;
+  }
+
   static X86Operand CreateReg(unsigned RegNo) {
     X86Operand Res;
     Res.Kind = Register;
     Res.Reg.RegNo = RegNo;
     return Res;
   }
+
   static X86Operand CreateImm(MCValue Val) {
     X86Operand Res;
     Res.Kind = Immediate;
     Res.Imm.Val = Val;
     return Res;
   }
+
   static X86Operand CreateMem(unsigned SegReg, MCValue Disp, unsigned BaseReg,
                               unsigned IndexReg, unsigned Scale) {
     // We should never just have a displacement, that would be an immediate.
@@ -326,7 +379,9 @@ bool X86ATTAsmParser::ParseMemOperand(X86Operand &Op) {
 }
 
 bool X86ATTAsmParser::ParseInstruction(const StringRef &Name, MCInst &Inst) {
-  SmallVector<X86Operand, 3> Operands;
+  SmallVector<X86Operand, 4> Operands;
+
+  Operands.push_back(X86Operand::CreateToken(Name));
 
   SMLoc Loc = getLexer().getTok().getLoc();
   if (getLexer().isNot(AsmToken::EndOfStatement)) {
@@ -345,7 +400,7 @@ bool X86ATTAsmParser::ParseInstruction(const StringRef &Name, MCInst &Inst) {
     }
   }
 
-  if (!MatchInstruction(Name, Operands, Inst))
+  if (!MatchInstruction(Operands, Inst))
     return false;
 
   // FIXME: We should give nicer diagnostics about the exact failure.
@@ -362,137 +417,4 @@ extern "C" void LLVMInitializeX86AsmParser() {
   RegisterAsmParser<X86ATTAsmParser> Y(TheX86_64Target);
 }
 
-// FIXME: These should come from tblgen?
-
-static bool 
-Match_X86_Op_REG(const X86Operand &Op, MCOperand *MCOps, unsigned NumOps) {
-  assert(NumOps == 1 && "Invalid number of ops!");
-
-  // FIXME: Match correct registers.
-  if (Op.Kind != X86Operand::Register)
-    return true;
-
-  MCOps[0] = MCOperand::CreateReg(Op.getReg());
-  return false;
-}
-
-static bool 
-Match_X86_Op_IMM(const X86Operand &Op, MCOperand *MCOps, unsigned NumOps) {
-  assert(NumOps == 1 && "Invalid number of ops!");
-
-  // FIXME: We need to check widths.
-  if (Op.Kind != X86Operand::Immediate)
-    return true;
-
-  MCOps[0] = MCOperand::CreateMCValue(Op.getImm());
-  return false;
-}
-
-static bool Match_X86_Op_LMEM(const X86Operand &Op,
-                             MCOperand *MCOps,
-                             unsigned NumMCOps) {
-  assert(NumMCOps == 4 && "Invalid number of ops!");
-
-  if (Op.Kind != X86Operand::Memory)
-    return true;
-
-  MCOps[0] = MCOperand::CreateReg(Op.getMemBaseReg());
-  MCOps[1] = MCOperand::CreateImm(Op.getMemScale());
-  MCOps[2] = MCOperand::CreateReg(Op.getMemIndexReg());
-  MCOps[3] = MCOperand::CreateMCValue(Op.getMemDisp());
-
-  return false;  
-}
-
-static bool Match_X86_Op_MEM(const X86Operand &Op,
-                             MCOperand *MCOps,
-                             unsigned NumMCOps) {
-  assert(NumMCOps == 5 && "Invalid number of ops!");
-
-  if (Match_X86_Op_LMEM(Op, MCOps, 4))
-    return true;
-
-  MCOps[4] = MCOperand::CreateReg(Op.getMemSegReg());
-
-  return false;  
-}
-
-#define REG(name) \
-  static bool Match_X86_Op_##name(const X86Operand &Op, \
-                                  MCOperand *MCOps,     \
-                                  unsigned NumMCOps) {  \
-    return Match_X86_Op_REG(Op, MCOps, NumMCOps);       \
-  }
-
-REG(GR64)
-REG(GR32)
-REG(GR16)
-REG(GR8)
-
-#define IMM(name) \
-  static bool Match_X86_Op_##name(const X86Operand &Op, \
-                                  MCOperand *MCOps,     \
-                                  unsigned NumMCOps) {  \
-    return Match_X86_Op_IMM(Op, MCOps, NumMCOps);       \
-  }
-
-IMM(brtarget)
-IMM(brtarget8)
-IMM(i16i8imm)
-IMM(i16imm)
-IMM(i32i8imm)
-IMM(i32imm)
-IMM(i32imm_pcrel)
-IMM(i64i32imm)
-IMM(i64i32imm_pcrel)
-IMM(i64i8imm)
-IMM(i64imm)
-IMM(i8imm)
-
-#define LMEM(name) \
-  static bool Match_X86_Op_##name(const X86Operand &Op, \
-                                  MCOperand *MCOps,     \
-                                  unsigned NumMCOps) {  \
-    return Match_X86_Op_LMEM(Op, MCOps, NumMCOps);       \
-  }
-
-LMEM(lea32mem)
-LMEM(lea64_32mem)
-LMEM(lea64mem)
-
-#define MEM(name) \
-  static bool Match_X86_Op_##name(const X86Operand &Op, \
-                                  MCOperand *MCOps,     \
-                                  unsigned NumMCOps) {  \
-    return Match_X86_Op_MEM(Op, MCOps, NumMCOps);       \
-  }
-
-MEM(f128mem)
-MEM(f32mem)
-MEM(f64mem)
-MEM(f80mem)
-MEM(i128mem)
-MEM(i16mem)
-MEM(i32mem)
-MEM(i64mem)
-MEM(i8mem)
-MEM(sdmem)
-MEM(ssmem)
-
-#define DUMMY(name) \
-  static bool Match_X86_Op_##name(const X86Operand &Op, \
-                                  MCOperand *MCOps,     \
-                                  unsigned NumMCOps) {  \
-    return true;                                        \
-  }
-
-DUMMY(FR32)
-DUMMY(FR64)
-DUMMY(GR32_NOREX)
-DUMMY(GR8_NOREX)
-DUMMY(RST)
-DUMMY(VR128)
-DUMMY(VR64)
-DUMMY(i8mem_NOREX)
-
 #include "X86GenAsmMatcher.inc"