Parse basic blocks and instructions.

Create map entries for ebbs and values as they are defined, but leave ebb and
value operands unresolved on instructions as they are parsed. Instruction
operands can refer to ebbs and values that may not have been defined yet.

Don't infer or check result types yet.

cranelift/src/libcretonne/entities.rs

@@ -105,6 +105,12 @@ pub enum ExpandedValue {
 }
 
 impl Value {
+    pub fn direct_from_number(n: u32) -> Value {
+        let encoding = n * 2;
+        assert!(encoding < u32::MAX);
+        Value(encoding)
+    }
+
     pub fn new_direct(i: Inst) -> Value {
         let encoding = i.index() * 2;
         assert!(encoding < u32::MAX as usize);

cranelift/src/libcretonne/repr.rs

@@ -19,6 +19,9 @@ pub struct Function {
     /// Signature of this function.
     signature: Signature,
 
+    /// The entry block.
+    pub entry_block: Ebb,
+
     /// Stack slots allocated in this function.
     stack_slots: Vec<StackSlotData>,
 
@@ -45,6 +48,7 @@ impl Function {
         Function {
             name: name,
             signature: sig,
+            entry_block: NO_EBB,
             stack_slots: Vec::new(),
             instructions: Vec::new(),
             extended_basic_blocks: Vec::new(),

cranelift/src/libreader/lexer.rs

@@ -36,7 +36,7 @@ pub enum Token<'a> {
     Integer(&'a str), // Integer immediate
     Type(types::Type), // i32, f32, b32x4, ...
     ValueDirect(u32), // v12
-    ValueExtended(u32), // vx7
+    ValueTable(u32), // vx7
     Ebb(u32), // ebb3
     StackSlot(u32), // ss3
     Identifier(&'a str), // Unrecognized identifier (opcode, enumerator, ...)
@@ -290,7 +290,7 @@ impl<'a> Lexer<'a> {
 
         match prefix {
             "v" => Some(Token::ValueDirect(value)),
-            "vx" => Some(Token::ValueExtended(value)),
+            "vx" => Some(Token::ValueTable(value)),
             "ebb" => Some(Token::Ebb(value)),
             "ss" => Some(Token::StackSlot(value)),
             _ => None,
@@ -452,7 +452,7 @@ mod tests {
         assert_eq!(lex.next(), token(Token::Identifier("ebb5234567890"), 1));
         assert_eq!(lex.next(), token(Token::Entry, 1));
         assert_eq!(lex.next(), token(Token::Identifier("v1x"), 1));
-        assert_eq!(lex.next(), token(Token::ValueExtended(1), 1));
+        assert_eq!(lex.next(), token(Token::ValueTable(1), 1));
         assert_eq!(lex.next(), token(Token::Identifier("vxvx4"), 1));
         assert_eq!(lex.next(), token(Token::Identifier("function0"), 1));
         assert_eq!(lex.next(), token(Token::Function, 1));

cranelift/src/libreader/parser.rs

@@ -10,9 +10,10 @@ use std::result;
 use std::fmt::{self, Display, Formatter, Write};
 use std::u32;
 use lexer::{self, Lexer, Token};
-use cretonne::types::{FunctionName, Signature, ArgumentType, ArgumentExtension};
-use cretonne::immediates::Imm64;
-use cretonne::entities::StackSlot;
+use cretonne::types::{Type, VOID, FunctionName, Signature, ArgumentType, ArgumentExtension};
+use cretonne::immediates::{Imm64, Ieee32, Ieee64};
+use cretonne::entities::*;
+use cretonne::instructions::{Opcode, InstructionFormat, InstructionData};
 use cretonne::repr::{Function, StackSlotData};
 
 pub use lexer::Location;
@@ -50,7 +51,10 @@ pub struct Parser<'a> {
 // file by number. We need to map these numbers to real references.
 struct Context {
     function: Function,
-    stack_slots: HashMap<u32, StackSlot>,
+    stack_slots: HashMap<u32, StackSlot>, // ssNN
+    ebbs: HashMap<u32, Ebb>, // ebbNN
+    value_directs: HashMap<u32, Value>, // vNN
+    value_tables: HashMap<u32, Value>, // vxNN
 }
 
 impl Context {
@@ -58,10 +62,14 @@ impl Context {
         Context {
             function: f,
             stack_slots: HashMap::new(),
+            ebbs: HashMap::new(),
+            value_directs: HashMap::new(),
+            value_tables: HashMap::new(),
         }
     }
 
-    fn add(&mut self, number: u32, data: StackSlotData, loc: &Location) -> Result<()> {
+    // Allocate a new stack slot and add a mapping number -> StackSlot.
+    fn add_ss(&mut self, number: u32, data: StackSlotData, loc: &Location) -> Result<()> {
         if self.stack_slots.insert(number, self.function.make_stack_slot(data)).is_some() {
             Err(Error {
                 location: loc.clone(),
@@ -71,6 +79,43 @@ impl Context {
             Ok(())
         }
     }
+
+    // Allocate a new EBB and add a mapping number -> Ebb.
+    fn add_ebb(&mut self, number: u32, loc: &Location) -> Result<Ebb> {
+        let ebb = self.function.make_ebb();
+        if self.ebbs.insert(number, ebb).is_some() {
+            Err(Error {
+                location: loc.clone(),
+                message: format!("duplicate EBB: ebb{}", number),
+            })
+        } else {
+            Ok(ebb)
+        }
+    }
+
+    // Add a value mapping number -> data for a direct value (vNN).
+    fn add_v(&mut self, number: u32, data: Value, loc: &Location) -> Result<()> {
+        if self.value_directs.insert(number, data).is_some() {
+            Err(Error {
+                location: loc.clone(),
+                message: format!("duplicate value: v{}", number),
+            })
+        } else {
+            Ok(())
+        }
+    }
+
+    // Add a value mapping number -> data for a table value (vxNN).
+    fn add_vx(&mut self, number: u32, data: Value, loc: &Location) -> Result<()> {
+        if self.value_tables.insert(number, data).is_some() {
+            Err(Error {
+                location: loc.clone(),
+                message: format!("duplicate value: vx{}", number),
+            })
+        } else {
+            Ok(())
+        }
+    }
 }
 
 impl<'a> Parser<'a> {
@@ -154,6 +199,16 @@ impl<'a> Parser<'a> {
         }
     }
 
+    // Match and consume a type.
+    fn match_type(&mut self, err_msg: &str) -> Result<Type> {
+        if let Some(Token::Type(t)) = self.token() {
+            self.consume();
+            Ok(t)
+        } else {
+            Err(self.error(err_msg))
+        }
+    }
+
     // Match and consume a stack slot reference.
     fn match_ss(&mut self, err_msg: &str) -> Result<u32> {
         if let Some(Token::StackSlot(ss)) = self.token() {
@@ -164,6 +219,38 @@ impl<'a> Parser<'a> {
         }
     }
 
+    // Match and consume an ebb reference.
+    fn match_ebb(&mut self, err_msg: &str) -> Result<u32> {
+        if let Some(Token::Ebb(ebb)) = self.token() {
+            self.consume();
+            Ok(ebb)
+        } else {
+            Err(self.error(err_msg))
+        }
+    }
+
+    // Match and consume a vx reference.
+    fn match_vx(&mut self, err_msg: &str) -> Result<u32> {
+        if let Some(Token::ValueTable(vx)) = self.token() {
+            self.consume();
+            Ok(vx)
+        } else {
+            Err(self.error(err_msg))
+        }
+    }
+
+    // Match and consume a value reference, direct or vtable.
+    // This does not convert from the source value numbering to our in-memory value numbering.
+    fn match_value(&mut self, err_msg: &str) -> Result<Value> {
+        let val = match self.token() {
+            Some(Token::ValueDirect(v)) => Value::direct_from_number(v),
+            Some(Token::ValueTable(vx)) => Value::new_table(vx as usize),
+            _ => return Err(self.error(err_msg)),
+        };
+        self.consume();
+        Ok(val)
+    }
+
     // Match and consume an Imm64 immediate.
     fn match_imm64(&mut self, err_msg: &str) -> Result<Imm64> {
         if let Some(Token::Integer(text)) = self.token() {
@@ -176,6 +263,30 @@ impl<'a> Parser<'a> {
         }
     }
 
+    // Match and consume an Ieee32 immediate.
+    fn match_ieee32(&mut self, err_msg: &str) -> Result<Ieee32> {
+        if let Some(Token::Float(text)) = self.token() {
+            self.consume();
+            // Lexer just gives us raw text that looks like a float.
+            // Parse it as an Ieee32 to check for the right number of digits and other issues.
+            text.parse().map_err(|e| self.error(e))
+        } else {
+            Err(self.error(err_msg))
+        }
+    }
+
+    // Match and consume an Ieee64 immediate.
+    fn match_ieee64(&mut self, err_msg: &str) -> Result<Ieee64> {
+        if let Some(Token::Float(text)) = self.token() {
+            self.consume();
+            // Lexer just gives us raw text that looks like a float.
+            // Parse it as an Ieee64 to check for the right number of digits and other issues.
+            text.parse().map_err(|e| self.error(e))
+        } else {
+            Err(self.error(err_msg))
+        }
+    }
+
     /// Parse a list of function definitions.
     ///
     /// This is the top-level parse function matching the whole contents of a file.
@@ -199,6 +310,8 @@ impl<'a> Parser<'a> {
         try!(self.match_token(Token::LBrace, "expected '{' before function body"));
         // function ::= function-spec "{" * preample function-body "}"
         try!(self.parse_preamble(&mut ctx));
+        // function ::= function-spec "{"  preample * function-body "}"
+        try!(self.parse_function_body(&mut ctx));
         // function ::= function-spec "{" preample function-body * "}"
         try!(self.match_token(Token::RBrace, "expected '}' after function body"));
 
@@ -279,12 +392,7 @@ impl<'a> Parser<'a> {
     // Parse a single argument type with flags.
     fn parse_argument_type(&mut self) -> Result<ArgumentType> {
         // arg ::= * type { flag }
-        let mut arg = if let Some(Token::Type(t)) = self.token() {
-            ArgumentType::new(t)
-        } else {
-            return Err(self.error("expected argument type"));
-        };
-        self.consume();
+        let mut arg = ArgumentType::new(try!(self.match_type("expected argument type")));
 
         // arg ::= type * { flag }
         while let Some(Token::Identifier(s)) = self.token() {
@@ -313,7 +421,7 @@ impl<'a> Parser<'a> {
             try!(match self.token() {
                 Some(Token::StackSlot(..)) => {
                     self.parse_stack_slot_decl()
-                        .and_then(|(num, dat)| ctx.add(num, dat, &self.location))
+                        .and_then(|(num, dat)| ctx.add_ss(num, dat, &self.location))
                 }
                 // More to come..
                 _ => return Ok(()),
@@ -339,6 +447,221 @@ impl<'a> Parser<'a> {
         // TBD: stack-slot-decl ::= StackSlot(ss) "=" "stack_slot" Bytes * {"," stack-slot-flag}
         Ok((number, data))
     }
+
+    // Parse a function body, add contents to `ctx`.
+    //
+    // function-body ::= * { extended-basic-block }
+    //
+    fn parse_function_body(&mut self, ctx: &mut Context) -> Result<()> {
+        while self.token() != Some(Token::RBrace) {
+            try!(self.parse_extended_basic_block(ctx));
+        }
+        Ok(())
+    }
+
+    // Parse an extended basic block, add contents to `ctx`.
+    //
+    // extended-basic-block ::= * ebb-header { instruction }
+    // ebb-header           ::= ["entry"] Ebb(ebb) [ebb-args] ":"
+    //
+    fn parse_extended_basic_block(&mut self, ctx: &mut Context) -> Result<()> {
+        let is_entry = self.optional(Token::Entry);
+        let ebb_num = try!(self.match_ebb("expected EBB header"));
+        let ebb = try!(ctx.add_ebb(ebb_num, &self.location));
+
+        if is_entry {
+            if ctx.function.entry_block != NO_EBB {
+                return Err(self.error("multiple entry blocks in function"));
+            }
+            ctx.function.entry_block = ebb;
+        }
+
+        if !self.optional(Token::Colon) {
+            // ebb-header ::= ["entry"] Ebb(ebb) [ * ebb-args ] ":"
+            try!(self.parse_ebb_args(ctx, ebb));
+            try!(self.match_token(Token::Colon, "expected ':' after EBB arguments"));
+        }
+
+        // extended-basic-block ::= ebb-header * { instruction }
+        while match self.token() {
+            Some(Token::ValueDirect(_)) => true,
+            Some(Token::Identifier(_)) => true,
+            _ => false,
+        } {
+            try!(self.parse_instruction(ctx, ebb));
+        }
+
+        Ok(())
+    }
+
+    // Parse parenthesized list of EBB arguments. Returns a vector of (u32, Type) pairs with the
+    // source vx numbers of the defined values and the defined types.
+    //
+    // ebb-args ::= * "(" ebb-arg { "," ebb-arg } ")"
+    fn parse_ebb_args(&mut self, ctx: &mut Context, ebb: Ebb) -> Result<()> {
+        // ebb-args ::= * "(" ebb-arg { "," ebb-arg } ")"
+        try!(self.match_token(Token::LPar, "expected '(' before EBB arguments"));
+
+        // ebb-args ::= "(" * ebb-arg { "," ebb-arg } ")"
+        try!(self.parse_ebb_arg(ctx, ebb));
+
+        // ebb-args ::= "(" ebb-arg * { "," ebb-arg } ")"
+        while self.optional(Token::Comma) {
+            // ebb-args ::= "(" ebb-arg { "," * ebb-arg } ")"
+            try!(self.parse_ebb_arg(ctx, ebb));
+        }
+
+        // ebb-args ::= "(" ebb-arg { "," ebb-arg } * ")"
+        try!(self.match_token(Token::RPar, "expected ')' after EBB arguments"));
+
+        Ok(())
+    }
+
+    // Parse a single EBB argument declaration, and append it to `ebb`.
+    //
+    // ebb-arg ::= * ValueTable(vx) ":" Type(t)
+    //
+    fn parse_ebb_arg(&mut self, ctx: &mut Context, ebb: Ebb) -> Result<()> {
+        // ebb-arg ::= * ValueTable(vx) ":" Type(t)
+        let vx = try!(self.match_vx("EBB argument must be a vx value"));
+        let vx_location = self.location;
+        // ebb-arg ::= ValueTable(vx) * ":" Type(t)
+        try!(self.match_token(Token::Colon, "expected ':' after EBB argument"));
+        // ebb-arg ::= ValueTable(vx) ":" * Type(t)
+        let t = try!(self.match_type("expected EBB argument type"));
+        // Allocate the EBB argument and add the mapping.
+        let value = ctx.function.append_ebb_arg(ebb, t);
+        ctx.add_vx(vx, value, &vx_location)
+    }
+
+    // Parse an instruction, append it to `ebb`.
+    //
+    // instruction ::= [inst-results "="] Opcode(opc) ...
+    // inst-results ::= ValueDirect(v) { "," ValueTable(vx) }
+    //
+    fn parse_instruction(&mut self, ctx: &mut Context, ebb: Ebb) -> Result<()> {
+        // Result value numbers. First is a ValueDirect, remaining are ValueTable.
+        let mut results = Vec::new();
+
+        // instruction ::=  * [inst-results "="] Opcode(opc) ...
+        if let Some(Token::ValueDirect(v)) = self.token() {
+            self.consume();
+            results.push(v);
+
+            // inst-results ::= ValueDirect(v) * { "," ValueTable(vx) }
+            while self.optional(Token::Comma) {
+                // inst-results ::= ValueDirect(v) { "," * ValueTable(vx) }
+                results.push(try!(self.match_vx("expected vx result value")));
+            }
+
+            try!(self.match_token(Token::Equal, "expected '=' before opcode"));
+        }
+
+        // instruction ::=  [inst-results "="] * Opcode(opc) ...
+        let opcode = if let Some(Token::Identifier(text)) = self.token() {
+            match text.parse() {
+                Ok(opc) => opc,
+                Err(msg) => return Err(self.error(msg)),
+            }
+        } else {
+            return Err(self.error("expected instruction opcode"));
+        };
+
+        // instruction ::=  [inst-results "="] Opcode(opc) * ...
+        let inst_data = try!(self.parse_inst_operands(opcode));
+        let inst = ctx.function.make_inst(inst_data);
+
+        // TODO: Check that results.len() matches the opcode.
+        // TODO: Multiple results.
+        if !results.is_empty() {
+            assert!(results.len() == 1, "Multiple results not implemented");
+            let result = ctx.function.first_result(inst);
+            try!(ctx.add_v(results[0], result, &self.location));
+        }
+
+        ctx.function.append_inst(ebb, inst);
+
+        Ok(())
+    }
+
+    // Parse the operands following the instruction opcode.
+    // This depends on the format of the opcode.
+    fn parse_inst_operands(&mut self, opcode: Opcode) -> Result<InstructionData> {
+        Ok(match opcode.format().unwrap() {
+            InstructionFormat::Nullary => {
+                InstructionData::Nullary {
+                    opcode: opcode,
+                    ty: VOID,
+                }
+            }
+            InstructionFormat::Unary => {
+                InstructionData::Unary {
+                    opcode: opcode,
+                    ty: VOID,
+                    arg: try!(self.match_value("expected SSA value operand")),
+                }
+            }
+            InstructionFormat::UnaryImm => {
+                InstructionData::UnaryImm {
+                    opcode: opcode,
+                    ty: VOID,
+                    imm: try!(self.match_imm64("expected immediate integer operand")),
+                }
+            }
+            InstructionFormat::UnaryIeee32 => {
+                InstructionData::UnaryIeee32 {
+                    opcode: opcode,
+                    ty: VOID,
+                    imm: try!(self.match_ieee32("expected immediate 32-bit float operand")),
+                }
+            }
+            InstructionFormat::UnaryIeee64 => {
+                InstructionData::UnaryIeee64 {
+                    opcode: opcode,
+                    ty: VOID,
+                    imm: try!(self.match_ieee64("expected immediate 64-bit float operand")),
+                }
+            }
+            InstructionFormat::UnaryImmVector => {
+                unimplemented!();
+            }
+            InstructionFormat::Binary => {
+                let lhs = try!(self.match_value("expected SSA value first operand"));
+                try!(self.match_token(Token::Comma, "expected ',' between operands"));
+                let rhs = try!(self.match_value("expected SSA value second operand"));
+                InstructionData::Binary {
+                    opcode: opcode,
+                    ty: VOID,
+                    args: [lhs, rhs],
+                }
+            }
+            InstructionFormat::BinaryImm => {
+                let lhs = try!(self.match_value("expected SSA value first operand"));
+                try!(self.match_token(Token::Comma, "expected ',' between operands"));
+                let rhs = try!(self.match_imm64("expected immediate integer second operand"));
+                InstructionData::BinaryImm {
+                    opcode: opcode,
+                    ty: VOID,
+                    lhs: lhs,
+                    rhs: rhs,
+                }
+            }
+            InstructionFormat::BinaryImmRev => {
+                let lhs = try!(self.match_imm64("expected immediate integer first operand"));
+                try!(self.match_token(Token::Comma, "expected ',' between operands"));
+                let rhs = try!(self.match_value("expected SSA value second operand"));
+                InstructionData::BinaryImmRev {
+                    opcode: opcode,
+                    ty: VOID,
+                    lhs: lhs,
+                    rhs: rhs,
+                }
+            }
+            InstructionFormat::Call => {
+                unimplemented!();
+            }
+        })
+    }
 }
 
 #[cfg(test)]
@@ -400,7 +723,7 @@ mod tests {
         assert_eq!(func[ss1].size, 1);
         assert_eq!(iter.next(), None);
 
-        // Catch suplicate definitions.
+        // Catch duplicate definitions.
         assert_eq!(Parser::new("function bar() {
                                     ss1  = stack_slot 13
                                     ss1  = stack_slot 1
@@ -410,4 +733,26 @@ mod tests {
                        .to_string(),
                    "3: duplicate stack slot: ss1");
     }
+
+    #[test]
+    fn ebb_header() {
+        let func = Parser::new("function ebbs() {
+                                ebb0:
+                                ebb4(vx3: i32):
+                                }")
+                       .parse_function()
+                       .unwrap();
+        assert_eq!(func.name, "ebbs");
+
+        let mut ebbs = func.ebbs_numerically();
+
+        let ebb0 = ebbs.next().unwrap();
+        assert_eq!(func.ebb_args(ebb0).next(), None);
+
+        let ebb4 = ebbs.next().unwrap();
+        let mut ebb4_args = func.ebb_args(ebb4);
+        let arg0 = ebb4_args.next().unwrap();
+        assert_eq!(func.value_type(arg0), types::I32);
+        assert_eq!(ebb4_args.next(), None);
+    }
 }