Changed C-- parser to allow multiple return values

[ghc-hetmet.git] / compiler / cmm / CmmParse.y

diff --git a/compiler/cmm/CmmParse.y b/compiler/cmm/CmmParse.y
index b3f68a9..4690f69 100644 (file)
--- a/compiler/cmm/CmmParse.y
+++ b/compiler/cmm/CmmParse.y
@@ -104,6 +104,7 @@ import System.Exit
        'jump'          { L _ (CmmT_jump) }
        'foreign'       { L _ (CmmT_foreign) }
        'prim'          { L _ (CmmT_prim) }
+       'return'        { L _ (CmmT_return) }
        'import'        { L _ (CmmT_import) }
        'switch'        { L _ (CmmT_switch) }
        'case'          { L _ (CmmT_case) }
@@ -253,24 +254,16 @@ stmt      :: { ExtCode }
        | NAME ':'
                { do l <- newLabel $1; code (labelC l) }
 
-       | lreg '=' expr ';'                     
-               { do reg <- $1; e <- $3; stmtEC (CmmAssign reg e) }
+-- HACK: this should just be lregs but that causes a shift/reduce conflict
+-- with foreign calls
+       | hint_lregs '=' expr ';'
+               { do reg <- head $1; e <- $3; stmtEC (CmmAssign (fst reg) e) }
        | type '[' expr ']' '=' expr ';'
                { doStore $1 $3 $6 }
-       | 'foreign' STRING expr '(' hint_exprs0 ')' vols ';'
-               {% foreignCall $2 [] $3 $5 $7 }
-       | lreg '=' 'foreign' STRING expr '(' hint_exprs0 ')' vols ';'
-               {% let result = do r <- $1; return (r,NoHint) in
-                  foreignCall $4 [result] $5 $7 $9 }
-       | 'prim' '%' NAME '(' hint_exprs0 ')' vols ';'
-               {% primCall [] $3 $5 $7 }
-       | lreg '=' 'prim' '%' NAME '(' hint_exprs0 ')' vols ';'
-               {% let result = do r <- $1; return (r,NoHint) in
-                  primCall [result] $5 $7 $9 }
-       | STRING lreg '=' 'foreign' STRING expr '(' hint_exprs0 ')' vols ';'
-               {% do h <- parseHint $1;
-                     let result = do r <- $2; return (r,h) in
-                     foreignCall $5 [result] $6 $8 $10 }
+       | maybe_results 'foreign' STRING expr '(' hint_exprs0 ')' vols ';'
+               {% foreignCall $3 $1 $4 $6 $8 }
+       | maybe_results 'prim' '%' NAME '(' hint_exprs0 ')' vols ';'
+               {% primCall $1 $4 $6 $8 }
        -- stmt-level macros, stealing syntax from ordinary C-- function calls.
        -- Perhaps we ought to use the %%-form?
        | NAME '(' exprs0 ')' ';'
@@ -279,8 +272,10 @@ stmt       :: { ExtCode }
                { doSwitch $2 $3 $5 $6 }
        | 'goto' NAME ';'
                { do l <- lookupLabel $2; stmtEC (CmmBranch l) }
-       | 'jump' expr {-maybe_actuals-} ';'
-               { do e <- $2; stmtEC (CmmJump e []) }
+       | 'jump' expr maybe_actuals ';'
+               { do e1 <- $2; e2 <- sequence $3; stmtEC (CmmJump e1 e2) }
+        | 'return' maybe_actuals ';'
+               { do e <- sequence $2; stmtEC (CmmReturn e) }
        | 'if' bool_expr '{' body '}' else      
                { ifThenElse $2 $4 $6 }
 
@@ -372,6 +367,10 @@ maybe_ty :: { MachRep }
        : {- empty -}                   { wordRep }
        | '::' type                     { $2 }
 
+maybe_actuals :: { [ExtFCode (CmmExpr, MachHint)] }
+       : {- empty -}           { [] }
+       | '(' hint_exprs0 ')'   { $2 }
+
 hint_exprs0 :: { [ExtFCode (CmmExpr, MachHint)] }
        : {- empty -}                   { [] }
        | hint_exprs                    { $1 }
@@ -398,6 +397,21 @@ reg        :: { ExtFCode CmmExpr }
        : NAME                  { lookupName $1 }
        | GLOBALREG             { return (CmmReg (CmmGlobal $1)) }
 
+maybe_results :: { [ExtFCode (CmmReg, MachHint)] }
+       : {- empty -}           { [] }
+       | hint_lregs '='        { $1 }
+
+hint_lregs :: { [ExtFCode (CmmReg, MachHint)] }
+       : hint_lreg ','                 { [$1] }
+       | hint_lreg                     { [$1] }
+       | hint_lreg ',' hint_lregs      { $1 : $3 }
+
+hint_lreg :: { ExtFCode (CmmReg, MachHint) }
+       : lreg                          { do e <- $1; return (e, inferHint (CmmReg e)) }
+       | STRING lreg                   {% do h <- parseHint $1;
+                                             return $ do
+                                               e <- $2; return (e,h) }
+
 lreg   :: { ExtFCode CmmReg }
        : NAME                  { do e <- lookupName $1;
                                     return $
@@ -760,15 +774,17 @@ foreignCall
        -> ExtFCode CmmExpr
        -> [ExtFCode (CmmExpr,MachHint)]
        -> Maybe [GlobalReg] -> P ExtCode
-foreignCall "C" results_code expr_code args_code vols
-  = return $ do
-       results <- sequence results_code
-       expr <- expr_code
-       args <- sequence args_code
-        code (emitForeignCall' PlayRisky results 
-                 (CmmForeignCall expr CCallConv) args vols)
-foreignCall conv _ _ _ _
-  = fail ("unknown calling convention: " ++ conv)
+foreignCall conv_string results_code expr_code args_code vols
+  = do  convention <- case conv_string of
+          "C" -> return CCallConv
+          "C--" -> return CmmCallConv
+          _ -> fail ("unknown calling convention: " ++ conv_string)
+       return $ do
+         results <- sequence results_code
+         expr <- expr_code
+         args <- sequence args_code
+          code (emitForeignCall' PlayRisky results 
+                 (CmmForeignCall expr convention) args vols) where
 
 primCall
        :: [ExtFCode (CmmReg,MachHint)]