X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fcmm%2FCmmOpt.hs;h=aa5a788d5e4872007e9e37c1e28588777865c703;hb=bd3a364da7956c269d31645995d0d775c52f6a84;hp=eba96531f3253131c153ee468b0c8baa7324f14f;hpb=d5c5c4eb1d9f6d382d3ef1a12be284a411451788;p=ghc-hetmet.git

diff --git a/compiler/cmm/CmmOpt.hs b/compiler/cmm/CmmOpt.hs
index eba9653..aa5a788 100644
--- a/compiler/cmm/CmmOpt.hs
+++ b/compiler/cmm/CmmOpt.hs
@@ -140,7 +140,7 @@ lookForInline u expr (stmt:stmts)
 getStmtUses :: CmmStmt -> UniqFM Int
 getStmtUses (CmmAssign _ e) = getExprUses e
 getStmtUses (CmmStore e1 e2) = plusUFM_C (+) (getExprUses e1) (getExprUses e2)
-getStmtUses (CmmCall target _ es _)
+getStmtUses (CmmCall target _ es)
    = plusUFM_C (+) (uses target) (getExprsUses (map fst es))
    where uses (CmmForeignCall e _) = getExprUses e
 	 uses _ = emptyUFM
@@ -161,8 +161,8 @@ getExprsUses es = foldr (plusUFM_C (+)) emptyUFM (map getExprUses es)
 inlineStmt :: Unique -> CmmExpr -> CmmStmt -> CmmStmt
 inlineStmt u a (CmmAssign r e) = CmmAssign r (inlineExpr u a e)
 inlineStmt u a (CmmStore e1 e2) = CmmStore (inlineExpr u a e1) (inlineExpr u a e2)
-inlineStmt u a (CmmCall target regs es vols)
-   = CmmCall (infn target) regs es' vols
+inlineStmt u a (CmmCall target regs es)
+   = CmmCall (infn target) regs es'
    where infn (CmmForeignCall fn cconv) = CmmForeignCall fn cconv
 	 infn (CmmPrim p) = CmmPrim p
 	 es' = [ (inlineExpr u a e, hint) | (e,hint) <- es ]
@@ -339,6 +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 _))]