X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fcmm%2FCmmOpt.hs;h=9a5121541a824a677c9863b5083b4ff66181a72a;hb=8e3b5645e0bab683444c81bbbac87e2df6799959;hp=a23a46f3503b19ef5fbcdbddfdd398546f8d7ed0;hpb=91a9aeebdf06c8c47a3b0eaf48ef297e7d460601;p=ghc-hetmet.git

diff --git a/compiler/cmm/CmmOpt.hs b/compiler/cmm/CmmOpt.hs
index a23a46f..9a51215 100644
--- a/compiler/cmm/CmmOpt.hs
+++ b/compiler/cmm/CmmOpt.hs
@@ -15,22 +15,21 @@ module CmmOpt (
 #include "HsVersions.h"
 
 import Cmm
-import CmmUtils	( hasNoGlobalRegs )
-import CLabel	( entryLblToInfoLbl )
+import CmmUtils
+import CLabel
 import MachOp
-import SMRep	( tablesNextToCode )
+import SMRep
+import StaticFlags
 
 import UniqFM
-import Unique	( Unique )
-import Panic	( panic )
+import Unique
 
 import Outputable
 
-import Bits
-import Word
-import Int
-import GLAEXTS
-
+import Data.Bits
+import Data.Word
+import Data.Int
+import GHC.Exts
 
 -- -----------------------------------------------------------------------------
 -- The mini-inliner
@@ -313,8 +312,12 @@ cmmMachOpFold op [x@(CmmLit _), y]
 -- put arg1 on the left of the rearranged expression, we'll get into a
 -- loop:  (x1+x2)+x3 => x1+(x2+x3)  => (x2+x3)+x1 => x2+(x3+x1) ...
 --
+-- Also don't do it if arg1 is PicBaseReg, so that we don't separate the
+-- PicBaseReg from the corresponding label (or label difference).
+--
 cmmMachOpFold mop1 [CmmMachOp mop2 [arg1,arg2], arg3]
-   | mop1 == mop2 && isAssociativeMachOp mop1 && not (isLit arg1)
+   | mop1 == mop2 && isAssociativeMachOp mop1
+     && not (isLit arg1) && not (isPicReg arg1)
    = cmmMachOpFold mop1 [arg1, cmmMachOpFold mop2 [arg2,arg3]]
 
 -- Make a RegOff if we can
@@ -336,6 +339,38 @@ cmmMachOpFold (MO_Add _) [CmmLit (CmmInt i rep), CmmLit (CmmLabel lbl)]
 cmmMachOpFold (MO_Sub _) [CmmLit (CmmLabel lbl), CmmLit (CmmInt i rep)]
   = CmmLit (CmmLabelOff lbl (fromIntegral (negate (narrowU rep i))))
 
+
+-- Comparison of literal with narrowed/widened operand: perform
+-- the comparison at a different width, as long as the literal is
+-- within range.
+
+#if i386_TARGET_ARCH || x86_64_TARGET_ARCH
+-- powerPC NCG has a TODO for I8/I16 comparisons, so don't try
+
+cmmMachOpFold cmp [CmmMachOp conv [x], CmmLit (CmmInt i _)]
+  | Just (rep, narrow) <- maybe_conversion conv,
+    Just narrow_cmp <- maybe_comparison cmp rep,
+    let narrow_i = narrow rep i,
+    narrow_i == i
+  = cmmMachOpFold narrow_cmp [x, CmmLit (CmmInt narrow_i rep)]
+ where
+    maybe_conversion (MO_U_Conv from _) = Just (from, narrowU)
+    maybe_conversion (MO_S_Conv from _) = Just (from, narrowS)
+    maybe_conversion _ = Nothing
+    
+    maybe_comparison (MO_U_Gt _) rep = Just (MO_U_Gt rep)
+    maybe_comparison (MO_U_Ge _) rep = Just (MO_U_Ge rep)
+    maybe_comparison (MO_U_Lt _) rep = Just (MO_U_Lt rep)
+    maybe_comparison (MO_U_Le _) rep = Just (MO_U_Le rep)
+    maybe_comparison (MO_S_Gt _) rep = Just (MO_S_Gt rep)
+    maybe_comparison (MO_S_Ge _) rep = Just (MO_S_Ge rep)
+    maybe_comparison (MO_S_Lt _) rep = Just (MO_S_Lt rep)
+    maybe_comparison (MO_S_Le _) rep = Just (MO_S_Le rep)
+    maybe_comparison (MO_Eq   _) rep = Just (MO_Eq   rep)
+    maybe_comparison _ _ = Nothing
+
+#endif
+
 -- We can often do something with constants of 0 and 1 ...
 
 cmmMachOpFold mop args@[x, y@(CmmLit (CmmInt 0 _))]
@@ -528,3 +563,6 @@ maybeInvertConditionalExpr :: CmmExpr -> Maybe CmmExpr
 maybeInvertConditionalExpr (CmmMachOp op args) 
   | Just op' <- maybeInvertComparison op = Just (CmmMachOp op' args)
 maybeInvertConditionalExpr _ = Nothing
+
+isPicReg (CmmReg (CmmGlobal PicBaseReg)) = True
+isPicReg _ = False