[commit: ghc] master: Narrow the args of the popCnt# primitives (new codegen) (e641139)

[Simon Marlow]

Repository : ssh://darcs.haskell.org//srv/darcs/ghc

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/e6411395563c3d425bc78a78b189b33eb3d3cc07

>---------------------------------------------------------------

commit e6411395563c3d425bc78a78b189b33eb3d3cc07
Author: Simon Marlow <marlowsd at gmail.com>
Date:   Mon Sep 3 12:28:35 2012 +0100

    Narrow the args of the popCnt# primitives (new codegen)
    
    (this change was previously done in the old codegen only)

>---------------------------------------------------------------

 compiler/codeGen/StgCmmPrim.hs |   15 ++++++++++-----
 1 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/compiler/codeGen/StgCmmPrim.hs b/compiler/codeGen/StgCmmPrim.hs
index 3a7a456..6c6005e 100644
--- a/compiler/codeGen/StgCmmPrim.hs
+++ b/compiler/codeGen/StgCmmPrim.hs
@@ -498,11 +498,16 @@ emitPrimOp [] SetByteArrayOp [ba,off,len,c] =
     doSetByteArrayOp ba off len c
 
 -- Population count
-emitPrimOp [res] PopCnt8Op [w] = emitPopCntCall res w W8
-emitPrimOp [res] PopCnt16Op [w] = emitPopCntCall res w W16
-emitPrimOp [res] PopCnt32Op [w] = emitPopCntCall res w W32
-emitPrimOp [res] PopCnt64Op [w] = emitPopCntCall res w W64
-emitPrimOp [res] PopCntOp [w] = emitPopCntCall res w wordWidth
+emitPrimOp [res] PopCnt8Op [w] =
+  emitPopCntCall res (CmmMachOp mo_WordTo8 [w]) W8
+emitPrimOp [res] PopCnt16Op [w] =
+  emitPopCntCall res (CmmMachOp mo_WordTo16 [w]) W16
+emitPrimOp [res] PopCnt32Op [w] =
+  emitPopCntCall res (CmmMachOp mo_WordTo32 [w]) W32
+emitPrimOp [res] PopCnt64Op [w] =
+  emitPopCntCall res w W64 -- arg always has type W64, no need to narrow
+emitPrimOp [res] PopCntOp [w] =
+  emitPopCntCall res w wordWidth
 
 -- The rest just translate straightforwardly
 emitPrimOp [res] op [arg]