LLVM: Code and speed improvement to dominateAllocs pass.

[ghc-hetmet.git] / compiler / llvmGen / LlvmCodeGen / CodeGen.hs

diff --git a/compiler/llvmGen/LlvmCodeGen/CodeGen.hs b/compiler/llvmGen/LlvmCodeGen/CodeGen.hs
index 3eb873e..076974a 100644 (file)
--- a/compiler/llvmGen/LlvmCodeGen/CodeGen.hs
+++ b/compiler/llvmGen/LlvmCodeGen/CodeGen.hs
@@ -26,10 +26,12 @@ import UniqSupply
 import Unique
 import Util
 
+import Data.List ( partition )
 import Control.Monad ( liftM )
 
 type LlvmStatements = OrdList LlvmStatement
 
+
 -- -----------------------------------------------------------------------------
 -- | Top-level of the LLVM proc Code generator
 --
@@ -62,9 +64,9 @@ basicBlocksCodeGen :: LlvmEnv
 basicBlocksCodeGen env ([]) (blocks, tops)
   = do let (blocks', allocs) = mapAndUnzip dominateAllocs blocks
        let allocs' = concat allocs
-       let ((BasicBlock id fstmts):rblocks) = blocks'
+       let ((BasicBlock id fstmts):rblks) = blocks'
        fplog <- funPrologue
-       let fblocks = (BasicBlock id (fplog ++  allocs' ++ fstmts)):rblocks
+       let fblocks = (BasicBlock id (fplog ++  allocs' ++ fstmts)):rblks
        return (env, fblocks, tops)
 
 basicBlocksCodeGen env (block:blocks) (lblocks', ltops')
@@ -74,6 +76,16 @@ basicBlocksCodeGen env (block:blocks) (lblocks', ltops')
        basicBlocksCodeGen env' blocks (lblocks, ltops)
 
 
+-- | Allocations need to be extracted so they can be moved to the entry
+-- of a function to make sure they dominate all possible paths in the CFG.
+dominateAllocs :: LlvmBasicBlock -> (LlvmBasicBlock, [LlvmStatement])
+dominateAllocs (BasicBlock id stmts)
+  = let (allocs, stmts') = partition isAlloc stmts
+        isAlloc (Assignment _ (Alloca _ _)) = True
+        isAlloc _other                      = False
+    in (BasicBlock id stmts', allocs)
+
+
 -- | Generate code for one block
 basicBlockCodeGen ::  LlvmEnv
                   -> CmmBasicBlock
@@ -83,19 +95,6 @@ basicBlockCodeGen env (BasicBlock id stmts)
        return (env', [BasicBlock id (fromOL instrs)], top)
 
 
--- | Allocations need to be extracted so they can be moved to the entry
--- of a function to make sure they dominate all possible paths in the CFG.
-dominateAllocs :: LlvmBasicBlock -> (LlvmBasicBlock, [LlvmStatement])
-dominateAllocs (BasicBlock id stmts)
-  = (BasicBlock id allstmts, allallocs)
-    where
-        (allstmts, allallocs) = foldl split ([],[]) stmts
-        split (stmts', allocs) s@(Assignment _ (Alloca _ _))
-            = (stmts', allocs ++ [s])
-        split (stmts', allocs) other
-            = (stmts' ++ [other], allocs)
-
-
 -- -----------------------------------------------------------------------------
 -- * CmmStmt code generation
 --