File 3311-Derive-ranges-from-matching-of-signed-inte... of Package erlang

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File 3311-Derive-ranges-from-matching-of-signed-integer-segmen.patch of Package erlang (Revision 3663bb9606f23c4ba295a87cfbbd490d)

Currently displaying revision 3663bb9606f23c4ba295a87cfbbd490d , Show latest

From 6ffcc0950307198882b8ac9ebc821a21de3dffeb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= <bjorn@erlang.org>
Date: Wed, 9 Feb 2022 08:33:10 +0100
Subject: [PATCH 1/2] Derive ranges from matching of signed integer segments

Derive ranges from matching of signed integer segments using the
binary syntax.
---
 lib/compiler/src/beam_ssa_type.erl  |  7 ++++---
 lib/compiler/src/beam_validator.erl | 17 ++++++++++++-----
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/lib/compiler/src/beam_ssa_type.erl b/lib/compiler/src/beam_ssa_type.erl
index 00b5f6db1e..487f793151 100644
--- a/lib/compiler/src/beam_ssa_type.erl
+++ b/lib/compiler/src/beam_ssa_type.erl
@@ -2208,12 +2208,13 @@ bs_match_type(integer, Args) ->
          #b_literal{val=Size},
          #b_literal{val=Unit}] when Size * Unit < 64 ->
             NumBits = Size * Unit,
+            Max = (1 bsl NumBits) - 1,
             case member(unsigned, Flags) of
                 true ->
-                    beam_types:make_integer(0, (1 bsl NumBits)-1);
+                    beam_types:make_integer(0, Max);
                 false ->
-                    %% Signed integer. Don't bother.
-                    #t_integer{}
+                    Min = -(Max + 1),
+                    beam_types:make_integer(Min, Max)
             end;
         [_|_] ->
             #t_integer{}
diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl
index 11f328b470..74b057e903 100644
--- a/lib/compiler/src/beam_validator.erl
+++ b/lib/compiler/src/beam_validator.erl
@@ -965,11 +965,18 @@ vi({test,bs_get_integer2=Op,{f,Fail},Live,
     NumBits = Unit * Sz,
     Stride = NumBits,
 
-    Type = case member(unsigned, Flags) of
-               true when 0 =< NumBits, NumBits =< 64 ->
-                   beam_types:make_integer(0, (1 bsl NumBits)-1);
-               _ ->
-                   %% Signed integer, way too large, or negative size.
+    Type = if
+               0 =< NumBits, NumBits =< 64 ->
+                   Max = (1 bsl NumBits) - 1,
+                   case member(unsigned, Flags) of
+                       true ->
+                           beam_types:make_integer(0, Max);
+                       false ->
+                           Min = -(Max + 1),
+                           beam_types:make_integer(Min, Max)
+                   end;
+               true ->
+                   %% Way too large or negative size.
                    #t_integer{}
            end,
 
-- 
2.34.1

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File 3311-Derive-ranges-from-matching-of-signed-integer-segmen.patch of Package erlang (Revision 3663bb9606f23c4ba295a87cfbbd490d)

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