remove shallowCopy for ARC/ORC (#20070)

* remove shallowCopy for ARC/ORC

* use move

* fix

* more fixes

* typo

* Update lib/system.nim

* follow

* add nodestroy

* move

* copy string

* add a changelog entry

Co-authored-by: xflywind <43030857+xflywind@users.noreply.github.com>
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>

5 files changed, 35 insertions, 9 deletions

diff --git a/compiler/btrees.nim b/compiler/btrees.nim
index 1701f8d7b..c79442249 100644
--- a/compiler/btrees.nim
+++ b/compiler/btrees.nim
@@ -68,7 +68,10 @@ proc copyHalf[Key, Val](h, result: Node[Key, Val]) =
       result.links[j] = h.links[Mhalf + j]
   else:
     for j in 0..<Mhalf:
-      shallowCopy(result.vals[j], h.vals[Mhalf + j])
+      when defined(gcArc) or defined(gcOrc):
+        result.vals[j] = move h.vals[Mhalf + j]
+      else:
+        shallowCopy(result.vals[j], h.vals[Mhalf + j])
 
 proc split[Key, Val](h: Node[Key, Val]): Node[Key, Val] =
   ## split node in half
@@ -88,7 +91,10 @@ proc insert[Key, Val](h: Node[Key, Val], key: Key, val: Val): Node[Key, Val] =
       if less(key, h.keys[j]): break
       inc j
     for i in countdown(h.entries, j+1):
-      shallowCopy(h.vals[i], h.vals[i-1])
+      when defined(gcArc) or defined(gcOrc):
+        h.vals[i] = move h.vals[i-1]
+      else:
+        shallowCopy(h.vals[i], h.vals[i-1])
     h.vals[j] = val
   else:
     var newLink: Node[Key, Val] = nil
diff --git a/compiler/msgs.nim b/compiler/msgs.nim
index 6d770e72f..ed65e0342 100644
--- a/compiler/msgs.nim
+++ b/compiler/msgs.nim
@@ -218,11 +218,18 @@ proc setDirtyFile*(conf: ConfigRef; fileIdx: FileIndex; filename: AbsoluteFile)
 
 proc setHash*(conf: ConfigRef; fileIdx: FileIndex; hash: string) =
   assert fileIdx.int32 >= 0
-  shallowCopy(conf.m.fileInfos[fileIdx.int32].hash, hash)
+  when defined(gcArc) or defined(gcOrc):
+    conf.m.fileInfos[fileIdx.int32].hash = hash
+  else:
+    shallowCopy(conf.m.fileInfos[fileIdx.int32].hash, hash)
+
 
 proc getHash*(conf: ConfigRef; fileIdx: FileIndex): string =
   assert fileIdx.int32 >= 0
-  shallowCopy(result, conf.m.fileInfos[fileIdx.int32].hash)
+  when defined(gcArc) or defined(gcOrc):
+    result = conf.m.fileInfos[fileIdx.int32].hash
+  else:
+    shallowCopy(result, conf.m.fileInfos[fileIdx.int32].hash)
 
 proc toFullPathConsiderDirty*(conf: ConfigRef; fileIdx: FileIndex): AbsoluteFile =
   if fileIdx.int32 < 0:
diff --git a/compiler/nimfix/prettybase.nim b/compiler/nimfix/prettybase.nim
index fbc2e3bd1..78c24bae3 100644
--- a/compiler/nimfix/prettybase.nim
+++ b/compiler/nimfix/prettybase.nim
@@ -22,7 +22,10 @@ proc replaceDeprecated*(conf: ConfigRef; info: TLineInfo; oldSym, newSym: PIdent
   let last = first+identLen(line, first)-1
   if cmpIgnoreStyle(line[first..last], oldSym.s) == 0:
     var x = line.substr(0, first-1) & newSym.s & line.substr(last+1)
-    system.shallowCopy(conf.m.fileInfos[info.fileIndex.int32].lines[info.line.int-1], x)
+    when defined(gcArc) or defined(gcOrc):
+      conf.m.fileInfos[info.fileIndex.int32].lines[info.line.int-1] = move x
+    else:
+      system.shallowCopy(conf.m.fileInfos[info.fileIndex.int32].lines[info.line.int-1], x)
     conf.m.fileInfos[info.fileIndex.int32].dirty = true
     #if newSym.s == "File": writeStackTrace()
 
@@ -35,5 +38,8 @@ proc replaceComment*(conf: ConfigRef; info: TLineInfo) =
   if line[first] != '#': inc first
 
   var x = line.substr(0, first-1) & "discard " & line.substr(first+1).escape
-  system.shallowCopy(conf.m.fileInfos[info.fileIndex.int32].lines[info.line.int-1], x)
+  when defined(gcArc) or defined(gcOrc):
+    conf.m.fileInfos[info.fileIndex.int32].lines[info.line.int-1] = move x
+  else:
+    system.shallowCopy(conf.m.fileInfos[info.fileIndex.int32].lines[info.line.int-1], x)
   conf.m.fileInfos[info.fileIndex.int32].dirty = true
diff --git a/compiler/pragmas.nim b/compiler/pragmas.nim
index 417941cd1..8c7d75024 100644
--- a/compiler/pragmas.nim
+++ b/compiler/pragmas.nim
@@ -511,7 +511,10 @@ proc processCompile(c: PContext, n: PNode) =
     n[i] = c.semConstExpr(c, n[i])
     case n[i].kind
     of nkStrLit, nkRStrLit, nkTripleStrLit:
-      shallowCopy(result, n[i].strVal)
+      when defined(gcArc) or defined(gcOrc):
+        result = n[i].strVal
+      else:
+        shallowCopy(result, n[i].strVal)
     else:
       localError(c.config, n.info, errStringLiteralExpected)
       result = ""
diff --git a/compiler/vm.nim b/compiler/vm.nim
index 3cb699482..28df27ef3 100644
--- a/compiler/vm.nim
+++ b/compiler/vm.nim
@@ -114,8 +114,12 @@ template decodeBx(k: untyped) {.dirty.} =
   let rbx = instr.regBx - wordExcess
   ensureKind(k)
 
-template move(a, b: untyped) {.dirty.} = system.shallowCopy(a, b)
-# XXX fix minor 'shallowCopy' overloading bug in compiler
+template move(a, b: untyped) {.dirty.} =
+  when defined(gcArc) or defined(gcOrc):
+    a = move b
+  else:
+    system.shallowCopy(a, b)
+    # XXX fix minor 'shallowCopy' overloading bug in compiler
 
 proc derefPtrToReg(address: BiggestInt, typ: PType, r: var TFullReg, isAssign: bool): bool =
   # nim bug: `isAssign: static bool` doesn't work, giving odd compiler error