Selection: CFG pipeline (ocaml-flambda#3073)

ccasin · Oct 23, 2024 · 43b57ce · 43b57ce
1 parent b066005
commit 43b57ce
Show file tree

Hide file tree

Showing 9 changed files with 1,304 additions and 43 deletions.
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
@@ -110,6 +110,13 @@ jobs:
             ocamlparam: '_,w=-46,regalloc=gi,regalloc-param=SPLIT_LIVE_RANGES:on,regalloc-param=GI_PRIORITY_HEURISTICS:interval-length,regalloc-param=GI_SELECTION_HEURISTICS:first-available,regalloc-param=GI_SPILLING_HEURISTICS:flat-uses,regalloc-validate=1,cfg-cse-optimize=1'
             check_arch: true
 
+          - name: cfg-selection
+            config: --enable-middle-end=flambda2
+            os: ubuntu-latest
+            build_ocamlparam: '_,w=-46,regalloc=cfg,cfg-cse-optimize=1,cfg-selection=1,cfg-zero-alloc-checker=1'
+            ocamlparam: '_,w=-46,regalloc=cfg,cfg-cse-optimize=1,cfg-selection=1,cfg-zero-alloc-checker=1'
+            check_arch: true
+
     env:
       J: "3"
       # On macOS, the testsuite is slow, so run only on push to main (#507)

diff --git a/backend/amd64/cfg_selection.ml b/backend/amd64/cfg_selection.ml
@@ -20,7 +20,9 @@
 open Arch
 open Selection_utils
 
-let specific x = Cfg_selectgen.Basic (Op (Specific x))
+let specific x =
+  assert (not (Arch.operation_can_raise x));
+  Cfg_selectgen.Basic (Op (Specific x))
 
 let pseudoregs_for_operation op arg res =
   match (op : Cfg.operation) with
@@ -318,4 +320,5 @@ class selector =
   end
 
 let fundecl ~future_funcnames f =
+  Cfg_selectgen.reset_next_instr_id ();
   (new selector)#emit_fundecl ~future_funcnames f
diff --git a/backend/arm64/cfg_selection.ml b/backend/arm64/cfg_selection.ml
@@ -23,7 +23,12 @@ open Arch
 open Cmm
 open Selection_utils
 
-let specific x = Cfg_selectgen.Basic Cfg.(Op (Specific x))
+let specific x =
+  if Arch.operation_can_raise x
+  then
+    Cfg_selectgen.With_next_label
+      (fun label_after -> Cfg.Specific_can_raise { Cfg.op = x; label_after })
+  else Cfg_selectgen.Basic Cfg.(Op (Specific x))
 
 class selector =
   object (self)
@@ -167,4 +172,5 @@ class selector =
   end
 
 let fundecl ~future_funcnames f =
+  Cfg_selectgen.reset_next_instr_id ();
   (new selector)#emit_fundecl ~future_funcnames f
diff --git a/backend/cfg/cfg.ml b/backend/cfg/cfg.ml
@@ -33,7 +33,7 @@ module DLL = Flambda_backend_utils.Doubly_linked_list
 type basic_instruction_list = basic instruction DLL.t
 
 type basic_block =
-  { start : Label.t;
+  { mutable start : Label.t;
     body : basic_instruction_list;
     mutable terminator : terminator instruction;
     mutable predecessors : Label.Set.t;

diff --git a/backend/cfg/cfg.mli b/backend/cfg/cfg.mli
@@ -35,7 +35,7 @@ type basic_instruction_list =
   basic instruction Flambda_backend_utils.Doubly_linked_list.t
 
 type basic_block =
-  { start : Label.t;
+  { mutable start : Label.t;
     body : basic_instruction_list;
     mutable terminator : terminator instruction;
     mutable predecessors : Label.Set.t;

diff --git a/backend/cfg/cfgize.ml b/backend/cfg/cfgize.ml
@@ -592,9 +592,10 @@ module Stack_offset_and_exn = struct
     match term.desc with
     | Tailcall_self _
       when stack_offset <> 0 || List.compare_length_with traps 0 <> 0 ->
-      Misc.fatal_error
+      Misc.fatal_errorf
         "Cfgize.Stack_offset_and_exn.process_terminator: unexpected handler on \
-         self tailcall"
+         self tailcall (id=%d)"
+        term.id
     | Never | Always _ | Parity_test _ | Truth_test _ | Float_test _
     | Int_test _ | Switch _ | Return | Raise _ | Tailcall_self _
     | Tailcall_func _ | Call_no_return _ | Call _ | Prim _
@@ -616,9 +617,10 @@ module Stack_offset_and_exn = struct
     | Poptrap -> (
       match traps with
       | [] ->
-        Misc.fatal_error
+        Misc.fatal_errorf
           "Cfgize.Stack_offset_and_exn.process_basic: trying to pop from an \
-           empty stack"
+           empty stack (id=%d)"
+          instr.id
       | _ :: traps -> stack_offset, traps)
     | Op (Stackoffset n) -> stack_offset + n, traps
     | Op

diff --git a/backend/cfg/cfgize.mli b/backend/cfg/cfgize.mli
@@ -1,3 +1,10 @@
+val terminator_of_test :
+  Mach.test -> label_false:Label.t -> label_true:Label.t -> Cfg.terminator
+
+module Stack_offset_and_exn : sig
+  val update_cfg : Cfg.t -> unit
+end
+
 val fundecl :
   Mach.fundecl ->
   before_register_allocation:bool ->