File 0157-Eliminate-internal-error-in-sub-pass-ssa_o... of Package erlang

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File 0157-Eliminate-internal-error-in-sub-pass-ssa_opt_ranges.patch of Package erlang

From 0cff4a3636f80c6b2ec037f80f8fe78ea163e2c5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= <bjorn@erlang.org>
Date: Fri, 4 Nov 2022 07:06:40 +0100
Subject: [PATCH] Eliminate internal error in sub pass ssa_opt_ranges

Closes #6427
---
 lib/compiler/src/beam_ssa_type.erl    | 14 ++++++++++-
 lib/compiler/test/beam_type_SUITE.erl | 34 +++++++++++++++++++++++++++
 2 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/lib/compiler/src/beam_ssa_type.erl b/lib/compiler/src/beam_ssa_type.erl
index dc38c23256..01120a6e10 100644
--- a/lib/compiler/src/beam_ssa_type.erl
+++ b/lib/compiler/src/beam_ssa_type.erl
@@ -920,8 +920,20 @@ update_anno_types_1([#b_var{}=V|As], Ts, Index, ArgTypes) ->
     case beam_types:meet(T0, T1) of
         any ->
             update_anno_types_1(As, Ts, Index + 1, ArgTypes);
+        none ->
+            %% This instruction will never be reached. This happens when
+            %% compiling code such as the following:
+            %%
+            %%   f(X) when is_integer(X), 0 =< X, X < 64 ->
+            %%        (X = bnot X) + 1.
+            %%
+            %% The main type optimization sub pass will not find out
+            %% that `(X = bnot X)` will never succeed and that the `+`
+            %% operator is never executed, but this sub pass will.
+            %% This happens very rarely; therefore, don't bother removing
+            %% the unreachable instruction.
+            update_anno_types_1(As, Ts, Index + 1, ArgTypes);
         T ->
-            true = T =/= none,                  %Assertion.
             update_anno_types_1(As, Ts, Index + 1, ArgTypes#{Index => T})
     end;
 update_anno_types_1([_|As], Ts, Index, ArgTypes) ->
diff --git a/lib/compiler/test/beam_type_SUITE.erl b/lib/compiler/test/beam_type_SUITE.erl
index 8e0e964185..35ecdaa4a7 100644
--- a/lib/compiler/test/beam_type_SUITE.erl
+++ b/lib/compiler/test/beam_type_SUITE.erl
@@ -119,6 +119,11 @@ integers(_Config) ->
 
     -693 = do_integers_9(id(7), id(1)),
 
+    {'EXIT',{{badmatch,42},_}} = catch do_integers_13(-43),
+    {'EXIT',{{badmatch,0},_}} = catch do_integers_13(-1),
+    {'EXIT',{{badmatch,-1},_}} = catch do_integers_13(0),
+    {'EXIT',{{badmatch,-18},_}} = catch do_integers_13(17),
+
     ok.
 
 do_integers_1(B0) ->
@@ -202,6 +207,35 @@ do_integers_11(V) ->
 do_integers_9(X, Y) ->
     X * (-100 bor (Y band 1)).
 
+%% GH-6427.
+do_integers_13(X) ->
+    try do_integers_13_1(<<X>>) of
+        _ -> error(should_fail)
+    catch
+        C:R:_ ->
+            try do_integers_13_2(X) of
+                _ -> error(should_fail)
+            catch
+                C:R:_ ->
+                    try do_integers_13_3(X) of
+                        _ -> error(should_fail)
+                    catch
+                        C:R:Stk ->
+                            erlang:raise(C, R, Stk)
+                    end
+            end
+    end.
+
+do_integers_13_1(<<X>>) ->
+    <<(X = bnot X)>>.
+
+do_integers_13_2(X) when is_integer(X), -64 < X, X < 64 ->
+    (X = bnot X) + 1.
+
+do_integers_13_3(X) when is_integer(X), -64 < X, X < 64 ->
+    X = bnot X,
+    X + 1.
+
 numbers(_Config) ->
     Int = id(42),
     true = is_integer(Int),
-- 
2.35.3

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File 0157-Eliminate-internal-error-in-sub-pass-ssa_opt_ranges.patch of Package erlang

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