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don't require an implementation for procs marked with .error; activate the move optimizer for destructors

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This commit is contained in:
Araq 2018-09-29 16:54:50 +02:00
commit 40e01d8549
5 changed files with 65 additions and 19 deletions
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47
compiler/destroyer.nim
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@ -181,7 +181,7 @@ proc isHarmlessVar*(s: PSym; c: Con): bool =
if c.g[i].sym == s:
if defsite < 0: defsite = i
else: return false
of use:
of use, useWithinCall:
if c.g[i].sym == s:
if defsite < 0: return false
for j in defsite .. i:
@ -190,10 +190,11 @@ proc isHarmlessVar*(s: PSym; c: Con): bool =
# if we want to die after the first 'use':
if usages > 1: return false
inc usages
of useWithinCall:
if c.g[i].sym == s: return false
#of useWithinCall:
# if c.g[i].sym == s: return false
of goto, fork:
discard "we do not perform an abstract interpretation yet"
result = usages <= 1
template interestingSym(s: PSym): bool =
s.owner == c.owner and s.kind in InterestingSyms and hasDestructor(s.typ)
@ -222,26 +223,35 @@ proc patchHead(s: PSym) =
if sfFromGeneric in s.flags:
patchHead(s.ast[bodyPos])
template genOp(opr, opname) =
proc checkForErrorPragma(c: Con; t: PType; ri: PNode; opname: string) =
var m = "'" & opname & "' is not available for type <" & typeToString(t) & ">"
if opname == "=" and ri != nil:
m.add "; requires a copy because it's not the last read of '"
m.add renderTree(ri)
m.add '\''
localError(c.graph.config, ri.info, errGenerated, m)
template genOp(opr, opname, ri) =
let op = opr
if op == nil:
globalError(c.graph.config, dest.info, "internal error: '" & opname & "' operator not found for type " & typeToString(t))
elif op.ast[genericParamsPos].kind != nkEmpty:
globalError(c.graph.config, dest.info, "internal error: '" & opname & "' operator is generic")
patchHead op
if sfError in op.flags: checkForErrorPragma(c, t, ri, opname)
result = newTree(nkCall, newSymNode(op), newTree(nkHiddenAddr, dest))
proc genSink(c: Con; t: PType; dest: PNode): PNode =
proc genSink(c: Con; t: PType; dest, ri: PNode): PNode =
let t = t.skipTypes({tyGenericInst, tyAlias, tySink})
genOp(if t.sink != nil: t.sink else: t.assignment, "=sink")
genOp(if t.sink != nil: t.sink else: t.assignment, "=sink", ri)
proc genCopy(c: Con; t: PType; dest: PNode): PNode =
proc genCopy(c: Con; t: PType; dest, ri: PNode): PNode =
let t = t.skipTypes({tyGenericInst, tyAlias, tySink})
genOp(t.assignment, "=")
genOp(t.assignment, "=", ri)
proc genDestroy(c: Con; t: PType; dest: PNode): PNode =
let t = t.skipTypes({tyGenericInst, tyAlias, tySink})
genOp(t.destructor, "=destroy")
genOp(t.destructor, "=destroy", nil)
proc addTopVar(c: var Con; v: PNode) =
c.topLevelVars.add newTree(nkIdentDefs, v, c.emptyNode, c.emptyNode)
@ -291,33 +301,33 @@ proc genMagicCall(n: PNode; c: var Con; magicname: string; m: TMagic): PNode =
proc moveOrCopy(dest, ri: PNode; c: var Con): PNode =
if ri.kind in constrExprs:
result = genSink(c, dest.typ, dest)
result = genSink(c, dest.typ, dest, ri)
# watch out and no not transform 'ri' twice if it's a call:
let ri2 = copyNode(ri)
recurse(ri, ri2)
result.add ri2
elif ri.kind == nkSym and isHarmlessVar(ri.sym, c):
elif ri.kind == nkSym and ri.sym.kind != skParam and isHarmlessVar(ri.sym, c):
# Rule 3: `=sink`(x, z); wasMoved(z)
var snk = genSink(c, dest.typ, dest)
var snk = genSink(c, dest.typ, dest, ri)
snk.add p(ri, c)
result = newTree(nkStmtList, snk, genMagicCall(ri, c, "wasMoved", mWasMoved))
elif ri.kind == nkSym and isSinkParam(ri.sym):
result = genSink(c, dest.typ, dest)
result = genSink(c, dest.typ, dest, ri)
result.add destructiveMoveSink(ri, c)
else:
result = genCopy(c, dest.typ, dest)
result = genCopy(c, dest.typ, dest, ri)
result.add p(ri, c)
proc passCopyToSink(n: PNode; c: var Con): PNode =
result = newNodeIT(nkStmtListExpr, n.info, n.typ)
let tmp = getTemp(c, n.typ, n.info)
if hasDestructor(n.typ):
var m = genCopy(c, n.typ, tmp)
var m = genCopy(c, n.typ, tmp, n)
m.add p(n, c)
result.add m
message(c.graph.config, n.info, hintPerformance,
"passing '$1' to a sink parameter introduces an implicit copy; " &
"use 'move($1)' to prevent it" % $n)
("passing '$1' to a sink parameter introduces an implicit copy; " &
"use 'move($1)' to prevent it") % $n)
else:
result.add newTree(nkAsgn, tmp, p(n, c))
result.add tmp
@ -331,6 +341,7 @@ proc destructiveMoveVar(n: PNode; c: var Con): PNode =
result = newNodeIT(nkStmtListExpr, n.info, n.typ)
var temp = newSym(skLet, getIdent(c.graph.cache, "blitTmp"), c.owner, n.info)
temp.typ = n.typ
var v = newNodeI(nkLetSection, n.info)
let tempAsNode = newSymNode(temp)
@ -410,7 +421,7 @@ proc p(n: PNode; c: var Con): PNode =
discard "produce temp creation"
result = newNodeIT(nkStmtListExpr, n.info, n.typ)
let tmp = getTemp(c, n.typ, n.info)
var sinkExpr = genSink(c, n.typ, tmp)
var sinkExpr = genSink(c, n.typ, tmp, n)
sinkExpr.add n
result.add sinkExpr
result.add tmp