Make dumping work with the irM.instN tagged InstId format

scripts/lldbinit.py

@@ -44,13 +44,16 @@ def print_usage() -> None:
 Dumps the value of an associated ID, using the C++ Dump() functions.
 
 Usage:
-  dump <CONTEXT> [<EXPR>|-- <EXPR>|<TYPE><ID>|<TYPE> <ID>]
+  dump <CONTEXT> [<EXPR>|-- <EXPR>|[<IR>.]<TYPE><ID>]
 
 Args:
   CONTEXT is the dump context, such a SemIR::Context reference, a SemIR::File,
           a Parse::Context, or a Lex::TokenizeBuffer.
   EXPR is a C++ expression such as a variable name. Use `--` to prevent it from
        being treated as a TYPE and ID.
+  IR is the CheckIRId(N) in the form `irN`. Not all ID types have an `ir`
+       prefix, the ones which do are dumped with that prefix, such as for
+       `inst` as `ir1.inst2`.
   TYPE can be `inst`, `constant`, `generic`, `impl`, `entity_name`, etc. See
        the `Label` string in `IdBase` classes to find possible TYPE names,
        though only Id types that have a matching `Make...Id()` function are
@@ -74,8 +77,13 @@ def print_usage() -> None:
 
     context = args[0]
 
-    # The set of "Make" functions in dump.cpp.
+    # The set of "Make" functions in dump.cpp. These use ADL to find the factory
+    # function in `check/` or in `sem_ir/`.
     id_types = {
+        "inst": "MakeInstId",
+    }
+    # These id types don't have an IdTag embedded in them.
+    untagged_id_types = {
         "class": "SemIR::MakeClassId",
         "constant": "SemIR::MakeConstantId",
         "symbolic_constant": "SemIR::MakeSymbolicConstantId",
@@ -85,7 +93,6 @@ def print_usage() -> None:
         "generic": "SemIR::MakeGenericId",
         "impl": "SemIR::MakeImplId",
         "inst_block": "SemIR::MakeInstBlockId",
-        "inst": "SemIR::MakeInstId",
         "interface": "SemIR::MakeInterfaceId",
         "name": "SemIR::MakeNameId",
         "name_scope": "SemIR::MakeNameScopeId",
@@ -110,27 +117,31 @@ def print_dump(context: str, expr: str) -> None:
 
     # Try to find a type + id from the input args. If not, the id will be passed
     # through directly to C++, as it can be a variable name.
-    id_type = None
+    found_id_type = False
 
-    # Look for <type><id> as a single argument.
-    if m := re.fullmatch("([a-z_]+)(\\d+)", args[1]):
-        if m[1] in id_types:
+    # Look for <irN>.<type><id> as a single argument.
+    if m := re.fullmatch("ir(\\d+)\\.([a-z_]+)(\\d+)", args[1]):
+        if m[2] in id_types:
             if len(args) != 2:
                 print_usage()
                 return
-            id_type = m[1]
-            print_dump(context, f"{id_types[id_type]}({m[2]})")
+            id_type = m[2]
+            print_dump(
+                context, f"{id_types[id_type]}({context}, {m[1]}, {m[3]})"
+            )
+            found_id_type = True
 
-    # Look for <type> <id> as two arguments.
-    if not id_type:
-        if args[1] in id_types:
-            if len(args) != 3:
+    # Look for <type><id> as a single argument.
+    if m := re.fullmatch("([a-z_]+)(\\d+)", args[1]):
+        if m[1] in untagged_id_types:
+            if len(args) != 2:
                 print_usage()
                 return
-            id_type = args[1]
-            print_dump(context, f"{id_types[id_type]}({args[2]})")
+            id_type = m[1]
+            print_dump(context, f"{untagged_id_types[id_type]}({m[2]})")
+            found_id_type = True
 
-    if not id_type:
+    if not found_id_type:
         # Use `--` to escape a variable name like `inst22`.
         if args[1] == "--":
             expr = " ".join(args[2:])

toolchain/check/BUILD

@@ -180,6 +180,7 @@ cc_library(
         "//toolchain/parse:tree",
         "//toolchain/sem_ir:dump",
         "//toolchain/sem_ir:file",
+        "//toolchain/sem_ir:typed_insts",
     ],
     # Always link dump methods.
     alwayslink = 1,

toolchain/check/context.h

@@ -243,6 +243,7 @@ class Context {
   // Directly expose SemIR::File data accessors for brevity in calls.
   // --------------------------------------------------------------------------
 
+  auto check_ir_id() -> SemIR::CheckIRId { return sem_ir().check_ir_id(); }
   auto identifiers() -> SharedValueStores::IdentifierStore& {
     return sem_ir().identifiers();
   }

toolchain/check/dump.cpp

@@ -25,6 +25,7 @@
 #include "toolchain/parse/tree.h"
 #include "toolchain/sem_ir/dump.h"
 #include "toolchain/sem_ir/file.h"
+#include "toolchain/sem_ir/ids.h"
 
 namespace Carbon::Check {
 
@@ -138,6 +139,17 @@ LLVM_DUMP_METHOD static auto Dump(const Context& context, SemIR::TypeId type_id)
   return SemIR::Dump(context.sem_ir(), type_id);
 }
 
+LLVM_DUMP_METHOD static auto MakeInstId(Context& context, int check_ir_id,
+                                        int id) -> SemIR::InstId {
+  if (SemIR::CheckIRId(check_ir_id) == context.check_ir_id()) {
+    return SemIR::MakeInstId(context.sem_ir(), check_ir_id, id);
+  } else {
+    const auto& import_ir = context.import_irs().Get(
+        context.check_ir_map().Get(SemIR::CheckIRId(check_ir_id)));
+    return SemIR::MakeInstId(*import_ir.sem_ir, check_ir_id, id);
+  }
+}
+
 }  // namespace Carbon::Check
 
 #endif  // NDEBUG

toolchain/sem_ir/dump.cpp

@@ -452,7 +452,16 @@ LLVM_DUMP_METHOD static auto MakeImplId(int id) -> ImplId { return ImplId(id); }
 LLVM_DUMP_METHOD static auto MakeInstBlockId(int id) -> InstBlockId {
   return InstBlockId(id);
 }
-LLVM_DUMP_METHOD static auto MakeInstId(int id) -> InstId { return InstId(id); }
+LLVM_DUMP_METHOD auto MakeInstId(const SemIR::File& file, int check_ir_id,
+                                 int id) -> InstId {
+  if (file.check_ir_id() != SemIR::CheckIRId(check_ir_id)) {
+    llvm::errs()
+        << "SemIR::MakeInstId given a CheckIRId for the wrong SemIR::File. "
+           "Maybe you want to dump from a Check::Context.\n";
+    return SemIR::InstId::None;
+  }
+  return InstId(file.insts().GetIdTag().Apply(id));
+}
 LLVM_DUMP_METHOD static auto MakeInterfaceId(int id) -> InterfaceId {
   return InterfaceId(id);
 }

toolchain/sem_ir/dump.h

@@ -42,6 +42,8 @@ auto Dump(const File& file, StructTypeFieldsId struct_type_fields_id)
     -> std::string;
 auto Dump(const File& file, TypeId type_id) -> std::string;
 
+auto MakeInstId(const SemIR::File& file, int check_ir_id, int id) -> InstId;
+
 }  // namespace Carbon::SemIR
 
 #endif  // NDEBUG