added system.newSeqOfCap for improved efficiency

1 files changed, 11 insertions, 0 deletions

diff --git a/compiler/ccgexprs.nim b/compiler/ccgexprs.nim
index 5f927ba78..c47478b9c 100644
--- a/compiler/ccgexprs.nim
+++ b/compiler/ccgexprs.nim
@@ -1141,6 +1141,16 @@ proc genNewSeq(p: BProc, e: PNode) =
   genNewSeqAux(p, a, b.rdLoc)
   gcUsage(e)
 
+proc genNewSeqOfCap(p: BProc; e: PNode; d: var TLoc) =
+  let seqtype = skipTypes(e.typ, abstractVarRange)
+  var a: TLoc
+  initLocExpr(p, e.sons[1], a)
+  putIntoDest(p, d, e.typ, ropecg(p.module,
+              "($1)#nimNewSeqOfCap($2, $3)", [
+              getTypeDesc(p.module, seqtype),
+              genTypeInfo(p.module, seqtype), a.rdLoc]))
+  gcUsage(e)
+
 proc genObjConstr(p: BProc, e: PNode, d: var TLoc) =
   var tmp: TLoc
   var t = e.typ.skipTypes(abstractInst)
@@ -1712,6 +1722,7 @@ proc genMagicExpr(p: BProc, e: PNode, d: var TLoc, op: TMagic) =
   of mNew: genNew(p, e)
   of mNewFinalize: genNewFinalize(p, e)
   of mNewSeq: genNewSeq(p, e)
+  of mNewSeqOfCap: genNewSeqOfCap(p, e, d)
   of mSizeOf:
     let t = e.sons[1].typ.skipTypes({tyTypeDesc})
     putIntoDest(p, d, e.typ, "((NI)sizeof($1))" % [getTypeDesc(p.module, t)])