Remove OldCmm, convert backends to consume new Cmm

This removes the OldCmm data type and the CmmCvt pass that converts
new Cmm to OldCmm.  The backends (NCGs, LLVM and C) have all been
converted to consume new Cmm.

The main difference between the two data types is that conditional
branches in new Cmm have both true/false successors, whereas in OldCmm
the false case was a fallthrough.  To generate slightly better code we
occasionally need to invert a conditional to ensure that the
branch-not-taken becomes a fallthrough; this was previously done in
CmmCvt, and it is now done in CmmContFlowOpt.

We could go further and use the Hoopl Block representation for native
code, which would mean that we could use Hoopl's postorderDfs and
analyses for native code, but for now I've left it as is, using the
old ListGraph representation for native code.

1 files changed, 38 insertions, 1 deletions

diff --git a/compiler/cmm/Cmm.hs b/compiler/cmm/Cmm.hs
index e1701bd4c5..0b3040d597 100644
--- a/compiler/cmm/Cmm.hs
+++ b/compiler/cmm/Cmm.hs
@@ -8,8 +8,13 @@ module Cmm (
      CmmDecl, GenCmmDecl(..),
      CmmGraph, GenCmmGraph(..),
      CmmBlock,
+     RawCmmDecl, RawCmmGroup,
      Section(..), CmmStatics(..), CmmStatic(..),
 
+     -- ** Blocks containing lists
+     GenBasicBlock(..), blockId,
+     ListGraph(..), pprBBlock,
+
      -- * Cmm graphs
      CmmReplGraph, GenCmmReplGraph, CmmFwdRewrite, CmmBwdRewrite,
    
@@ -31,6 +36,7 @@ import SMRep
 import CmmExpr
 import UniqSupply
 import Compiler.Hoopl
+import Outputable
 
 import Data.Word        ( Word8 )
 
@@ -50,6 +56,7 @@ type CmmProgram = [CmmGroup]
 
 type GenCmmGroup d h g = [GenCmmDecl d h g]
 type CmmGroup = GenCmmGroup CmmStatics CmmTopInfo CmmGraph
+type RawCmmGroup = GenCmmGroup CmmStatics (BlockEnv CmmStatics) CmmGraph
 
 -----------------------------------------------------------------------------
 --  CmmDecl, GenCmmDecl
@@ -62,7 +69,6 @@ type CmmGroup = GenCmmGroup CmmStatics CmmTopInfo CmmGraph
 --
 -- We expect there to be two main instances of this type:
 --   (a) C--, i.e. populated with various C-- constructs
---       (Cmm and RawCmm in OldCmm.hs)
 --   (b) Native code, populated with data/instructions
 
 -- | A top-level chunk, abstracted over the type of the contents of
@@ -87,6 +93,12 @@ data GenCmmDecl d h g
 
 type CmmDecl = GenCmmDecl CmmStatics CmmTopInfo CmmGraph
 
+type RawCmmDecl
+   = GenCmmDecl
+        CmmStatics
+        (BlockEnv CmmStatics)
+        CmmGraph
+
 -----------------------------------------------------------------------------
 --     Graphs
 -----------------------------------------------------------------------------
@@ -177,3 +189,28 @@ data CmmStatics
        CLabel      -- Label of statics
        [CmmStatic] -- The static data itself
 
+-- -----------------------------------------------------------------------------
+-- Basic blocks consisting of lists
+
+-- These are used by the LLVM and NCG backends, when populating Cmm
+-- with lists of instructions.
+
+data GenBasicBlock i = BasicBlock BlockId [i]
+
+-- | The branch block id is that of the first block in
+-- the branch, which is that branch's entry point
+blockId :: GenBasicBlock i -> BlockId
+blockId (BasicBlock blk_id _ ) = blk_id
+
+newtype ListGraph i = ListGraph [GenBasicBlock i]
+
+instance Outputable instr => Outputable (ListGraph instr) where
+    ppr (ListGraph blocks) = vcat (map ppr blocks)
+
+instance Outputable instr => Outputable (GenBasicBlock instr) where
+    ppr = pprBBlock
+
+pprBBlock :: Outputable stmt => GenBasicBlock stmt -> SDoc
+pprBBlock (BasicBlock ident stmts) =
+    hang (ppr ident <> colon) 4 (vcat (map ppr stmts))
+