[project @ 2005-02-01 15:33:14 by simonmar]

hack upon the hack: confine the hack to -fasm, because gcc is too
stupid to optimise away the extra temporary.

diff --git a/ghc/compiler/codeGen/CgInfoTbls.hs b/ghc/compiler/codeGen/CgInfoTbls.hs
index 981b4b0..0111a2a 100644 (file)
--- a/ghc/compiler/codeGen/CgInfoTbls.hs
+++ b/ghc/compiler/codeGen/CgInfoTbls.hs
@@ -57,7 +57,7 @@ import StgSyn         ( SRT(..) )
 import Name            ( Name )
 import DataCon         ( DataCon, dataConTag, fIRST_TAG )
 import Unique          ( Uniquable(..) )
-import CmdLineOpts     ( opt_SccProfilingOn )
+import CmdLineOpts     ( opt_SccProfilingOn, DynFlags(..), HscTarget(..) )
 import ListSetOps      ( assocDefault )
 import Maybes          ( isJust )
 import Constants       ( wORD_SIZE, sIZEOF_StgFunInfoExtraRev )
@@ -351,9 +351,17 @@ emitVectoredReturnInstr zero_indexed_tag
   = do { info_amode <- getSequelAmode
                -- HACK! assign info_amode to a temp, because retVec
                -- uses it twice and the NCG doesn't have any CSE yet.
-       ; x <- newTemp wordRep
-       ; stmtC (CmmAssign x info_amode)
-       ; let target = retVec (CmmReg x) zero_indexed_tag
+               -- Only do this for the NCG, because gcc is too stupid
+               -- to optimise away the extra tmp (grrr).
+       ; dflags <- getDynFlags
+       ; x <- if hscTarget dflags == HscAsm
+                  then do z <- newTemp wordRep
+                          stmtC (CmmAssign z info_amode)
+                          return (CmmReg z)
+                  else
+
+                       return info_amode
+       ; let target = retVec x zero_indexed_tag
        ; stmtC (CmmJump target []) }