Add popCnt# primop

compiler/cmm/CmmMachOp.hs

@@ -448,6 +448,8 @@ data CallishMachOp
   | MO_Memcpy
   | MO_Memset
   | MO_Memmove
+
+  | MO_PopCnt Width
   deriving (Eq, Show)
 
 pprCallishMachOp :: CallishMachOp -> SDoc

compiler/codeGen/CgPrimOp.hs

@@ -374,6 +374,12 @@ emitPrimOp [] CopyByteArrayOp [src,src_off,dst,dst_off,n] live =
 emitPrimOp [] CopyMutableByteArrayOp [src,src_off,dst,dst_off,n] live =
     doCopyMutableByteArrayOp src src_off dst dst_off n live
 
+-- Population count
+emitPrimOp [res] PopCnt8Op [w] live = emitPopCntCall res w W8 live
+emitPrimOp [res] PopCnt16Op [w] live = emitPopCntCall res w W16 live
+emitPrimOp [res] PopCnt32Op [w] live = emitPopCntCall res w W32 live
+emitPrimOp [res] PopCnt64Op [w] live = emitPopCntCall res w W64 live
+emitPrimOp [res] PopCntOp [w] live = emitPopCntCall res w wordWidth live
 
 -- The rest just translate straightforwardly
 emitPrimOp [res] op [arg] _
@@ -908,3 +914,14 @@ emitAllocateCall res cap n live = do
   where
     allocate = CmmLit (CmmLabel (mkForeignLabel (fsLit "allocate") Nothing
                                  ForeignLabelInExternalPackage IsFunction))
+
+emitPopCntCall :: LocalReg -> CmmExpr -> Width -> StgLiveVars -> Code
+emitPopCntCall res x width live = do
+    vols <- getVolatileRegs live
+    emitForeignCall' PlayRisky
+        [CmmHinted res NoHint]
+        (CmmPrim (MO_PopCnt width))
+        [(CmmHinted x NoHint)]
+        (Just vols)
+        NoC_SRT -- No SRT b/c we do PlayRisky
+        CmmMayReturn

compiler/codeGen/StgCmmPrim.hs

@@ -443,6 +443,13 @@ emitPrimOp [] CopyByteArrayOp [src,src_off,dst,dst_off,n] =
 emitPrimOp [] CopyMutableByteArrayOp [src,src_off,dst,dst_off,n] =
     doCopyMutableByteArrayOp src src_off dst dst_off n
 
+-- 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
+
 -- The rest just translate straightforwardly
 emitPrimOp [res] op [arg]
    | nopOp op
@@ -940,3 +947,10 @@ emitAllocateCall res cap n = do
   where
     allocate = CmmLit (CmmLabel (mkForeignLabel (fsLit "allocate") Nothing
                                  ForeignLabelInExternalPackage IsFunction))
+
+emitPopCntCall :: LocalReg -> CmmExpr -> Width -> FCode ()
+emitPopCntCall res x width = do
+    emitPrimCall
+        [ res ]
+        (MO_PopCnt width)
+        [ x ]

compiler/ghc.cabal.in

@@ -497,6 +497,7 @@ Library
             RegClass
             PIC
             Platform
+            CPrim
             X86.Regs
             X86.RegInfo
             X86.Instr

compiler/main/DynFlags.hs

@@ -276,6 +276,7 @@ data DynFlag
    | Opt_SharedImplib
    | Opt_BuildingCabalPackage
    | Opt_SSE2
+   | Opt_SSE4_2
    | Opt_GhciSandbox
    | Opt_HelpfulErrors
 
@@ -1518,6 +1519,7 @@ dynamic_flags = [
   , flagA "monly-3-regs" (NoArg (addWarn "The -monly-3-regs flag does nothing; it will be removed in a future GHC release"))
   , flagA "monly-4-regs" (NoArg (addWarn "The -monly-4-regs flag does nothing; it will be removed in a future GHC release"))
   , flagA "msse2"        (NoArg (setDynFlag Opt_SSE2))
+  , flagA "msse4.2"      (NoArg (setDynFlag Opt_SSE4_2))
 
      ------ Warning opts -------------------------------------------------
   , flagA "W"      (NoArg (mapM_ setWarningFlag minusWOpts))

compiler/nativeGen/CPrim.hs

+-- | Generating C symbol names emitted by the compiler.
+module CPrim (popCntLabel) where
+
+import CmmType
+import Outputable
+
+popCntLabel :: Width -> String
+popCntLabel w = "hs_popcnt" ++ pprWidth w
+  where
+    pprWidth W8  = "8"
+    pprWidth W16 = "16"
+    pprWidth W32 = "32"
+    pprWidth W64 = "64"
+    pprWidth w   = pprPanic "popCntLabel: Unsupported word width " (ppr w)

compiler/nativeGen/PPC/CodeGen.hs

@@ -28,6 +28,7 @@ where
 import PPC.Instr
 import PPC.Cond
 import PPC.Regs
+import CPrim
 import NCGMonad
 import Instruction
 import PIC
@@ -1142,6 +1143,8 @@ genCCall' gcp target dest_regs argsAndHints
                     MO_Memset    -> (fsLit "memset", False)
                     MO_Memmove   -> (fsLit "memmove", False)
 
+                    MO_PopCnt w  -> (fsLit $ popCntLabel w, False)
+
                     other -> pprPanic "genCCall(ppc): unknown callish op"
                                     (pprCallishMachOp other)
 

compiler/nativeGen/SPARC/CodeGen/CCall.hs

@@ -13,6 +13,7 @@ import SPARC.Instr
 import SPARC.Imm
 import SPARC.Regs
 import SPARC.Base
+import CPrim
 import NCGMonad
 import PIC
 import Instruction
@@ -332,5 +333,7 @@ outOfLineMachOp_table mop
         MO_Memset    -> fsLit "memset"
         MO_Memmove   -> fsLit "memmove"
 
+        MO_PopCnt w  -> fsLit $ popCntLabel w
+
 	_ -> pprPanic "outOfLineMachOp(sparc): Unknown callish mach op "
               		(pprCallishMachOp mop)

compiler/nativeGen/X86/CodeGen.hs

@@ -28,6 +28,7 @@ import X86.Instr
 import X86.Cond
 import X86.Regs
 import X86.RegInfo
+import CPrim
 import Instruction
 import PIC
 import NCGMonad
@@ -70,9 +71,14 @@ sse2Enabled = do
                     -- calling convention specifies the use of xmm regs,
                     -- and possibly other places.
                     return True
-      ArchX86    -> return (dopt Opt_SSE2 dflags)
+      ArchX86    -> return (dopt Opt_SSE2 dflags || dopt Opt_SSE4_2 dflags)
       _          -> panic "sse2Enabled: Not an X86* arch"
 
+sse4_2Enabled :: NatM Bool
+sse4_2Enabled = do
+  dflags <- getDynFlagsNat
+  return (dopt Opt_SSE4_2 dflags)
+
 if_sse2 :: NatM a -> NatM a -> NatM a
 if_sse2 sse2 x87 = do
   b <- sse2Enabled
@@ -1574,6 +1580,26 @@ genCCall (CmmPrim MO_WriteBarrier) _ _ = return nilOL
         -- write barrier compiles to no code on x86/x86-64;
         -- we keep it this long in order to prevent earlier optimisations.
 
+genCCall (CmmPrim (MO_PopCnt width)) dest_regs@[CmmHinted dst _]
+         args@[CmmHinted src _] = do
+    sse4_2 <- sse4_2Enabled
+    if sse4_2
+        then do code_src <- getAnyReg src
+                src_r <- getNewRegNat size
+                return $ code_src src_r `appOL`
+                    (if width == W8 then
+                         -- The POPCNT instruction doesn't take a r/m8
+                         unitOL (MOVZxL II8 (OpReg src_r) (OpReg src_r)) `appOL`
+                         unitOL (POPCNT II16 (OpReg src_r)
+                                 (getRegisterReg False (CmmLocal dst)))
+                     else
+                         unitOL (POPCNT size (OpReg src_r)
+                                 (getRegisterReg False (CmmLocal dst))))
+        else genCCall (CmmCallee (fn width) CCallConv) dest_regs args
+  where size = intSize width
+        fn w = CmmLit (CmmLabel (mkForeignLabel (fsLit (popCntLabel w)) Nothing
+                                 ForeignLabelInExternalPackage IsFunction))
+
 genCCall target dest_regs args =
     do dflags <- getDynFlagsNat
        if target32Bit (targetPlatform dflags)
@@ -1990,6 +2016,8 @@ outOfLineCmmOp mop res args
               MO_Memset    -> fsLit "memset"
               MO_Memmove   -> fsLit "memmove"
 
+              MO_PopCnt _  -> fsLit "popcnt"
+
               other -> panic $ "outOfLineCmmOp: unmatched op! (" ++ show other ++ ")"
 
 

compiler/nativeGen/X86/Instr.hs

@@ -310,6 +310,8 @@ data Instr
                           	 --       call 1f
                           	 -- 1:    popl %reg
 	
+    -- SSE4.2
+    | POPCNT      Size Operand Reg -- src, dst
 
 data Operand
 	= OpReg  Reg	        -- register
@@ -403,6 +405,8 @@ x86_regUsageOfInstr instr
     COMMENT _		-> noUsage
     DELTA   _           -> noUsage
 
+    POPCNT _ src dst -> mkRU (use_R src) [dst]
+
     _other		-> panic "regUsage: unrecognised instr"
 
  where
@@ -539,6 +543,8 @@ x86_patchRegsOfInstr instr env
     JXX_GBL _ _		-> instr
     CLTD _		-> instr
 
+    POPCNT sz src dst -> POPCNT sz (patchOp src) (env dst)
+
     _other		-> panic "patchRegs: unrecognised instr"
 
   where

compiler/nativeGen/X86/Ppr.hs

@@ -574,6 +574,8 @@ pprInstr platform (XOR FF32 src dst) = pprOpOp platform (sLit "xorps") FF32 src
 pprInstr platform (XOR FF64 src dst) = pprOpOp platform (sLit "xorpd") FF64 src dst
 pprInstr platform (XOR size src dst) = pprSizeOpOp platform (sLit "xor")  size src dst
 
+pprInstr platform (POPCNT size src dst) = pprOpOp platform (sLit "popcnt") size src (OpReg dst)
+
 pprInstr platform (NOT size op) = pprSizeOp platform (sLit "not") size op
 pprInstr platform (NEGI size op) = pprSizeOp platform (sLit "neg") size op
 

compiler/prelude/primops.txt.pp

@@ -302,6 +302,22 @@ primop   WordNeOp   "neWord#"   Compare   Word# -> Word# -> Bool
 primop   WordLtOp   "ltWord#"   Compare   Word# -> Word# -> Bool
 primop   WordLeOp   "leWord#"   Compare   Word# -> Word# -> Bool
 
+primop   PopCnt8Op   "popCnt8#"   Monadic   Word# -> Word#
+    {Count the number of set bits in the lower 8 bits of a word.}
+primop   PopCnt16Op   "popCnt16#"   Monadic   Word# -> Word#
+    {Count the number of set bits in the lower 16 bits of a word.}
+primop   PopCnt32Op   "popCnt32#"   Monadic   Word# -> Word#
+    {Count the number of set bits in the lower 32 bits of a word.}
+#if WORD_SIZE_IN_BITS < 64
+primop   PopCnt64Op   "popCnt64#"   Monadic   Word64# -> Word#
+    {Count the number of set bits in a 64-bit word.}
+#else
+primop   PopCnt64Op   "popCnt64#"   Monadic   Word# -> Word#
+    {Count the number of set bits in a 64-bit word.}
+#endif
+primop   PopCntOp   "popCnt#"   Monadic   Word# -> Word#
+    {Count the number of set bits in a word.}
+
 ------------------------------------------------------------------------
 section "Narrowings" 
 	{Explicit narrowing of native-sized ints or words.}
@@ -1926,6 +1942,3 @@ primop  TraceEventOp "traceEvent#" GenPrimOp
 ------------------------------------------------------------------------
 
 thats_all_folks
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