The fix for #4914 was wrong and broke other things (see #5149). We

[ghc-hetmet.git] / compiler / nativeGen / AsmCodeGen.lhs

diff --git a/compiler/nativeGen/AsmCodeGen.lhs b/compiler/nativeGen/AsmCodeGen.lhs
index 06e6d6d..27858dc 100644 (file)
--- a/compiler/nativeGen/AsmCodeGen.lhs
+++ b/compiler/nativeGen/AsmCodeGen.lhs
@@ -372,10 +372,25 @@ cmmNativeGen dflags us cmm count
                        , Nothing
                        , mPprStats)
 
-       ---- generate jump tables
+        ---- x86fp_kludge.  This pass inserts ffree instructions to clear
+        ---- the FPU stack on x86.  The x86 ABI requires that the FPU stack
+        ---- is clear, and library functions can return odd results if it
+        ---- isn't.
+        ----
+        ---- NB. must happen before shortcutBranches, because that
+        ---- generates JXX_GBLs which we can't fix up in x86fp_kludge.
+        let kludged =
+#if i386_TARGET_ARCH
+               {-# SCC "x86fp_kludge" #-}
+                map x86fp_kludge alloced
+#else
+                alloced
+#endif
+
+        ---- generate jump tables
        let tabled      =
                {-# SCC "generateJumpTables" #-}
-               alloced ++ generateJumpTables alloced
+                generateJumpTables kludged
 
        ---- shortcut branches
        let shorted     =
@@ -387,27 +402,18 @@ cmmNativeGen dflags us cmm count
                {-# SCC "sequenceBlocks" #-}
                map sequenceTop shorted
 
-       ---- x86fp_kludge
-       let kludged =
-#if i386_TARGET_ARCH
-               {-# SCC "x86fp_kludge" #-}
-               map x86fp_kludge sequenced
-#else
-               sequenced
-#endif
-
-       ---- expansion of SPARC synthetic instrs
+        ---- expansion of SPARC synthetic instrs
 #if sparc_TARGET_ARCH
        let expanded = 
                {-# SCC "sparc_expand" #-}
-               map expandTop kludged
+                map expandTop sequenced
 
        dumpIfSet_dyn dflags
                Opt_D_dump_asm_expanded "Synthetic instructions expanded"
                (vcat $ map (docToSDoc . pprNatCmmTop) expanded)
 #else
        let expanded = 
-               kludged
+                sequenced
 #endif
 
        return  ( usAlloc
@@ -615,8 +621,8 @@ makeFarBranches = id
 generateJumpTables
        :: [NatCmmTop Instr] -> [NatCmmTop Instr]
 generateJumpTables xs = concatMap f xs
-    where f (CmmProc _ _ (ListGraph xs)) = concatMap g xs
-          f _ = []
+    where f p@(CmmProc _ _ (ListGraph xs)) = p : concatMap g xs
+          f p = [p]
           g (BasicBlock _ xs) = catMaybes (map generateJumpTableForInstr xs)
 
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