IC: backend: remember produced type information (#17440)

compiler/ic/cbackend.nim

@@ -18,7 +18,7 @@
 ## also doing cross-module dependency tracking and DCE that we don't need
 ## anymore. DCE is now done as prepass over the entire packed module graph.
 
-import std/[packedsets, algorithm]
+import std/[packedsets, algorithm, tables]
   # std/intsets would give `UnusedImport`, pending https://github.com/nim-lang/Nim/issues/14246
 import ".."/[ast, options, lineinfos, modulegraphs, cgendata, cgen,
   pathutils, extccomp, msgs]
@@ -45,6 +45,10 @@ proc generateCodeForModule(g: ModuleGraph; m: var LoadedModule; alive: var Alive
 
   finalCodegenActions(g, bmod, newNodeI(nkStmtList, m.module.info))
 
+proc replayTypeInfo(g: ModuleGraph; m: var LoadedModule; origin: FileIndex) =
+  for x in mitems(m.fromDisk.emittedTypeInfo):
+    g.emittedTypeInfo[x] = origin
+
 proc addFileToLink(config: ConfigRef; m: PSym) =
   let filename = AbsoluteFile toFullPath(config, m.position.FileIndex)
   let ext =
@@ -59,11 +63,28 @@ proc addFileToLink(config: ConfigRef; m: PSym) =
                    flags: {CfileFlag.Cached})
     addFileToCompile(config, cf)
 
-proc aliveSymsChanged(config: ConfigRef; position: int; alive: AliveSyms): bool =
+when defined(debugDce):
+  import std / [os, packedsets]
+
+proc storeAliveSymsImpl(asymFile: AbsoluteFile; s: seq[int32]) =
+  var f = rodfiles.create(asymFile.string)
+  f.storeHeader()
+  f.storeSection aliveSymsSection
+  f.storeSeq(s)
+  close f
+
+template prepare {.dirty.} =
   let asymFile = toRodFile(config, AbsoluteFile toFullPath(config, position.FileIndex), ".alivesyms")
   var s = newSeqOfCap[int32](alive[position].len)
   for a in items(alive[position]): s.add int32(a)
   sort(s)
+
+proc storeAliveSyms(config: ConfigRef; position: int; alive: AliveSyms) =
+  prepare()
+  storeAliveSymsImpl(asymFile, s)
+
+proc aliveSymsChanged(config: ConfigRef; position: int; alive: AliveSyms): bool =
+  prepare()
   var f2 = rodfiles.open(asymFile.string)
   f2.loadHeader()
   f2.loadSection aliveSymsSection
@@ -73,12 +94,17 @@ proc aliveSymsChanged(config: ConfigRef; position: int; alive: AliveSyms): bool
   if f2.err == ok and oldData == s:
     result = false
   else:
+    when defined(debugDce):
+      let oldAsSet = toPackedSet[int32](oldData)
+      let newAsSet = toPackedSet[int32](s)
+      echo "set of live symbols changed ", asymFile.changeFileExt("rod"), " ", position, " ", f2.err
+      echo "in old but not in new ", oldAsSet.difference(newAsSet)
+      echo "in new but not in old ", newAsSet.difference(oldAsSet)
+
+      if execShellCmd(getAppFilename() & " rod " & quoteShell(asymFile.changeFileExt("rod"))) != 0:
+        echo "command failed"
     result = true
-    var f = rodfiles.create(asymFile.string)
-    f.storeHeader()
-    f.storeSection aliveSymsSection
-    f.storeSeq(s)
-    close f
+    storeAliveSymsImpl(asymFile, s)
 
 proc generateCode*(g: ModuleGraph) =
   ## The single entry point, generate C(++) code for the entire
@@ -95,6 +121,8 @@ proc generateCode*(g: ModuleGraph) =
       assert false
     of storing, outdated:
       generateCodeForModule(g, g.packed[i], alive)
+      closeRodFile(g, g.packed[i].module)
+      storeAliveSyms(g.config, g.packed[i].module.position, alive)
     of loaded:
       # Even though this module didn't change, DCE might trigger a change.
       # Consider this case: Module A uses symbol S from B and B does not use
@@ -104,3 +132,4 @@ proc generateCode*(g: ModuleGraph) =
         generateCodeForModule(g, g.packed[i], alive)
       else:
         addFileToLink(g.config, g.packed[i].module)
+        replayTypeInfo(g, g.packed[i], FileIndex(i))

compiler/ic/ic.nim

@@ -42,6 +42,8 @@ type
     methodsPerType*: seq[(PackedItemId, int, PackedItemId)]
     enumToStringProcs*: seq[(PackedItemId, PackedItemId)]
 
+    emittedTypeInfo*: seq[string]
+
     sh*: Shared
     cfg: PackedConfig
 
@@ -58,7 +60,7 @@ type
     config*: ConfigRef
 
 proc isActive*(e: PackedEncoder): bool = e.config != nil
-proc disable*(e: var PackedEncoder) = e.config = nil
+proc disable(e: var PackedEncoder) = e.config = nil
 
 template primConfigFields(fn: untyped) {.dirty.} =
   fn backend
@@ -552,6 +554,7 @@ proc loadRodFile*(filename: AbsoluteFile; m: var PackedModule; config: ConfigRef
   loadSeqSection attachedOpsSection, m.attachedOps
   loadSeqSection methodsPerTypeSection, m.methodsPerType
   loadSeqSection enumToStringProcsSection, m.enumToStringProcs
+  loadSeqSection typeInfoSection, m.emittedTypeInfo
 
   close(f)
   result = f.err
@@ -614,6 +617,7 @@ proc saveRodFile*(filename: AbsoluteFile; encoder: var PackedEncoder; m: var Pac
   storeSeqSection attachedOpsSection, m.attachedOps
   storeSeqSection methodsPerTypeSection, m.methodsPerType
   storeSeqSection enumToStringProcsSection, m.enumToStringProcs
+  storeSeqSection typeInfoSection, m.emittedTypeInfo
 
   close(f)
   encoder.disable()
@@ -1139,7 +1143,10 @@ proc rodViewer*(rodfile: AbsoluteFile; config: ConfigRef, cache: IdentCache) =
 
   echo "all symbols"
   for i in 0..high(m.sh.syms):
-    echo "  ", m.sh.strings[m.sh.syms[i].name], " local ID: ", i
+    if m.sh.syms[i].name != LitId(0):
+      echo "  ", m.sh.strings[m.sh.syms[i].name], " local ID: ", i, " kind ", m.sh.syms[i].kind
+    else:
+      echo "  <anon symbol?> local ID: ", i, " kind ", m.sh.syms[i].kind
 
   echo "symbols: ", m.sh.syms.len, " types: ", m.sh.types.len,
     " top level nodes: ", m.topLevel.nodes.len, " other nodes: ", m.bodies.nodes.len,

compiler/ic/rodfiles.nim

@@ -36,6 +36,7 @@ type
     attachedOpsSection
     methodsPerTypeSection
     enumToStringProcsSection
+    typeInfoSection  # required by the backend
     aliveSymsSection # beware, this is stored in a `.alivesyms` file.
 
   RodFileError* = enum