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Fix transformation of yield in inline context (#9135)

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When the loop variables are part of the envP block it is not safe to use
a nkFastAsgn.

Fixes #2656
This commit is contained in:
LemonBoy 2018-10-09 19:43:31 +02:00 • committed by Andreas Rumpf
commit f98a3056c6
2 changed files with 63 additions and 15 deletions
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43
compiler/transf.nim
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@ -110,8 +110,8 @@ proc transformSons(c: PTransf, n: PNode): PTransNode =
for i in countup(0, sonsLen(n)-1):
result[i] = transform(c, n.sons[i])
proc newAsgnStmt(c: PTransf, le: PNode, ri: PTransNode): PTransNode =
result = newTransNode(nkFastAsgn, PNode(ri).info, 2)
proc newAsgnStmt(c: PTransf, kind: TNodeKind, le: PNode, ri: PTransNode): PTransNode =
result = newTransNode(kind, PNode(ri).info, 2)
result[0] = PTransNode(le)
result[1] = ri
@ -299,12 +299,6 @@ proc transformBreak(c: PTransf, n: PNode): PTransNode =
else:
result = n.PTransNode
proc unpackTuple(c: PTransf, n: PNode, father: PTransNode) =
# XXX: BUG: what if `n` is an expression with side-effects?
for i in countup(0, sonsLen(c.transCon.forStmt) - 3):
add(father, newAsgnStmt(c, c.transCon.forStmt.sons[i],
transform(c, newTupleAccess(c.graph, n, i))))
proc introduceNewLocalVars(c: PTransf, n: PNode): PTransNode =
case n.kind
of nkSym:
@ -328,6 +322,18 @@ proc introduceNewLocalVars(c: PTransf, n: PNode): PTransNode =
result[i] = introduceNewLocalVars(c, n.sons[i])
proc transformYield(c: PTransf, n: PNode): PTransNode =
proc asgnTo(lhs: PNode, rhs: PTransNode): PTransNode =
# Choose the right assignment instruction according to the given ``lhs``
# node since it may not be a nkSym (a stack-allocated skForVar) but a
# nkDotExpr (a heap-allocated slot into the envP block)
case lhs.kind:
of nkSym:
internalAssert c.graph.config, lhs.sym.kind == skForVar
result = newAsgnStmt(c, nkFastAsgn, lhs, rhs)
of nkDotExpr:
result = newAsgnStmt(c, nkAsgn, lhs, rhs)
else:
internalAssert c.graph.config, false
result = newTransNode(nkStmtList, n.info, 0)
var e = n.sons[0]
# c.transCon.forStmt.len == 3 means that there is one for loop variable
@ -340,13 +346,20 @@ proc transformYield(c: PTransf, n: PNode): PTransNode =
for i in countup(0, sonsLen(e) - 1):
var v = e.sons[i]
if v.kind == nkExprColonExpr: v = v.sons[1]
add(result, newAsgnStmt(c, c.transCon.forStmt.sons[i],
transform(c, v)))
let lhs = c.transCon.forStmt.sons[i]
let rhs = transform(c, v)
add(result, asgnTo(lhs, rhs))
else:
unpackTuple(c, e, result)
# Unpack the tuple into the loop variables
# XXX: BUG: what if `n` is an expression with side-effects?
for i in countup(0, sonsLen(c.transCon.forStmt) - 3):
let lhs = c.transCon.forStmt.sons[i]
let rhs = transform(c, newTupleAccess(c.graph, e, i))
add(result, asgnTo(lhs, rhs))
else:
var x = transform(c, e)
add(result, newAsgnStmt(c, c.transCon.forStmt.sons[0], x))
let lhs = c.transCon.forStmt.sons[0]
let rhs = transform(c, e)
add(result, asgnTo(lhs, rhs))
inc(c.transCon.yieldStmts)
if c.transCon.yieldStmts <= 1:
@ -584,7 +597,7 @@ proc transformFor(c: PTransf, n: PNode): PTransNode =
# generate a temporary and produce an assignment statement:
var temp = newTemp(c, formal.typ, formal.info)
addVar(v, temp)
add(stmtList, newAsgnStmt(c, temp, arg.PTransNode))
add(stmtList, newAsgnStmt(c, nkFastAsgn, temp, arg.PTransNode))
idNodeTablePut(newC.mapping, formal, temp)
of paVarAsgn:
assert(skipTypes(formal.typ, abstractInst).kind == tyVar)
@ -595,7 +608,7 @@ proc transformFor(c: PTransf, n: PNode): PTransNode =
addSonSkipIntLit(typ, formal.typ.sons[0])
var temp = newTemp(c, typ, formal.info)
addVar(v, temp)
add(stmtList, newAsgnStmt(c, temp, arg.PTransNode))
add(stmtList, newAsgnStmt(c, nkFastAsgn, temp, arg.PTransNode))
idNodeTablePut(newC.mapping, formal, temp)
var body = iter.getBody.copyTree