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This commit is contained in:
Andrii Riabushenko
2018-11-30 09:36:04 +00:00
parent c0b91bc024
commit e90f70af42
1 changed files with 23 additions and 22 deletions
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45
compiler/destroyer.nim
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@@ -411,10 +411,12 @@ proc passCopyToSink(n: PNode; c: var Con): PNode =
result.add tmp
proc pArg(arg: PNode; c: var Con; isSink: bool): PNode =
if arg.typ == nil:
# typ is nil if we are in if/case branch with noreturn
result = copyTree(arg)
elif isSink:
template pArgIfTyped(arg_part: PNode): PNode =
# typ is nil if we are in if/case expr branch with noreturn
if arg_part.typ == nil: copyTree(arg_part)
else: pArg(arg_part, c, isSink)
if isSink:
if arg.kind in nkCallKinds:
# recurse but skip the call expression in order to prevent
# destructor injections: Rule 5.1 is different from rule 5.4!
@@ -446,9 +448,9 @@ proc pArg(arg: PNode; c: var Con; isSink: bool): PNode =
var branch = copyNode(arg[i])
if arg[i].kind in {nkElifBranch, nkElifExpr}:
branch.add p(arg[i][0], c)
branch.add pArg(arg[i][1], c, isSink)
branch.add pArgIfTyped(arg[i][1])
else:
branch.add pArg(arg[i][0], c, isSink)
branch.add pArgIfTyped(arg[i][0])
result.add branch
elif arg.kind == nkCaseStmt:
result = copyNode(arg)
@@ -457,14 +459,14 @@ proc pArg(arg: PNode; c: var Con; isSink: bool): PNode =
var branch: PNode
if arg[i].kind == nkOfbranch:
branch = arg[i] # of branch conditions are constants
branch[^1] = pArg(arg[i][^1], c, isSink)
branch[^1] = pArgIfTyped(arg[i][^1])
elif arg[i].kind in {nkElifBranch, nkElifExpr}:
branch = copyNode(arg[i])
branch.add p(arg[i][0], c)
branch.add pArg(arg[i][1], c, isSink)
branch.add pArgIfTyped(arg[i][1])
else:
branch = copyNode(arg[i])
branch.add pArg(arg[i][0], c, isSink)
branch.add pArgIfTyped(arg[i][0])
result.add branch
else:
# an object that is not temporary but passed to a 'sink' parameter
@@ -474,11 +476,12 @@ proc pArg(arg: PNode; c: var Con; isSink: bool): PNode =
result = p(arg, c)
proc moveOrCopy(dest, ri: PNode; c: var Con): PNode =
if ri.typ == nil:
# typ is nil if we are in if/case branch with noreturn
result = copyTree(ri)
else:
case ri.kind
template moveOrCopyIfTyped(ri_part: PNode): PNode =
# typ is nil if we are in if/case expr branch with noreturn
if ri_part.typ == nil: copyTree(ri_part)
else: moveOrCopy(dest, ri_part, c)
case ri.kind
of nkCallKinds:
result = genSink(c, dest.typ, dest, ri)
# watch out and no not transform 'ri' twice if it's a call:
@@ -505,18 +508,16 @@ proc moveOrCopy(dest, ri: PNode; c: var Con): PNode =
of nkBlockExpr, nkBlockStmt:
result = newNodeI(nkBlockStmt, ri.info)
result.add ri[0] ## add label
for i in 1..ri.len-2:
result.add p(ri[i], c)
result.add moveOrCopy(dest, ri[^1], c)
result.add moveOrCopy(dest, ri[1], c)
of nkIfExpr, nkIfStmt:
result = newNodeI(nkIfStmt, ri.info)
for i in 0..<ri.len:
var branch = copyNode(ri[i])
if ri[i].kind in {nkElifBranch, nkElifExpr}:
branch.add p(ri[i][0], c)
branch.add moveOrCopy(dest, ri[i][1], c)
branch.add moveOrCopyIfTyped(ri[i][1])
else:
branch.add moveOrCopy(dest, ri[i][0], c)
branch.add moveOrCopyIfTyped(ri[i][0])
result.add branch
of nkCaseStmt:
result = newNodeI(nkCaseStmt, ri.info)
@@ -525,14 +526,14 @@ proc moveOrCopy(dest, ri: PNode; c: var Con): PNode =
var branch: PNode
if ri[i].kind == nkOfbranch:
branch = ri[i] # of branch conditions are constants
branch[^1] = moveOrCopy(dest, ri[i][^1], c)
branch[^1] = moveOrCopyIfTyped(ri[i][^1])
elif ri[i].kind in {nkElifBranch, nkElifExpr}:
branch = copyNode(ri[i])
branch.add p(ri[i][0], c)
branch.add moveOrCopy(dest, ri[i][1], c)
branch.add moveOrCopyIfTyped(ri[i][1])
else:
branch = copyNode(ri[i])
branch.add moveOrCopy(dest, ri[i][0], c)
branch.add moveOrCopyIfTyped(ri[i][0])
result.add branch
of nkObjConstr:
result = genSink(c, dest.typ, dest, ri)