diff options
| -rw-r--r-- | erts/emulator/beam/macros.tab | 9 | ||||
| -rwxr-xr-x | erts/emulator/utils/beam_makeops | 54 |
2 files changed, 51 insertions, 12 deletions
diff --git a/erts/emulator/beam/macros.tab b/erts/emulator/beam/macros.tab index e0b5f56b53..494fe8961e 100644 --- a/erts/emulator/beam/macros.tab +++ b/erts/emulator/beam/macros.tab @@ -20,13 +20,12 @@ // // -// Use if there is a garbage collection before storing to a -// general destination (either X or Y register). +// Define a regular expression that will match instructions that +// perform GC. That will allow beam_makeops to check for instructions +// that don't use $REFRESH_GEN_DEST() when they should. // -REFRESH_GEN_DEST() { - dst_ptr = REG_TARGET_PTR(dst); -} +GC_REGEXP=erts_garbage_collect|erts_gc|GcBifFunction; // $Offset is relative to the start of the instruction (not to the // location of the failure label reference). Since combined diff --git a/erts/emulator/utils/beam_makeops b/erts/emulator/utils/beam_makeops index dc4da0cca0..3e1116ef52 100755 --- a/erts/emulator/utils/beam_makeops +++ b/erts/emulator/utils/beam_makeops @@ -19,7 +19,7 @@ # %CopyrightEnd% # use strict; -use vars qw($BEAM_FORMAT_NUMBER); +use vars qw($BEAM_FORMAT_NUMBER $GC_REGEXP); use constant COLD => 0; use constant WARM => 1; use constant HOT => 2; @@ -36,6 +36,7 @@ use constant PACK_CMD_LOOSE => '3'; use constant PACK_CMD_WIDE => '4'; $BEAM_FORMAT_NUMBER = undef; +$GC_REGEXP = undef; my $target = \&emulator_output; my $outdir = "."; # Directory for output files. @@ -310,6 +311,7 @@ my %predef_macros = (IS_PACKED => ['Expr'], OPERAND_POSITION => ['Expr'], IF => ['Expr','IfTrue','IfFalse'], + REFRESH_GEN_DEST => [], ); foreach my $name (keys %predef_macros) { my @args = @{$predef_macros{$name}}; @@ -392,8 +394,10 @@ while (<>) { # if (/^([\w_][\w\d_]+)=(.*)/) { no strict 'refs'; - my($name) = $1; - $$name = $2; + my $name = $1; + my $value = $2; + $value =~ s/;\s*$//; + $$name = $value; next; } @@ -1366,7 +1370,9 @@ sub cg_basic { # sub cg_combined_size { - my %params = (@_, pack_options => \@basic_pack_options); + my %params = (@_, + pack_options => \@basic_pack_options, + size_only => 1); $params{pack_options} = \@extended_pack_options if $params{first}; my($size) = code_gen(%params); @@ -1394,6 +1400,7 @@ sub code_gen { my %params = (extra_comments => '', offset => 0, inc => 0, + size_only => 0, @_); my $name = $params{name}; my $extra_comments = $params{extra_comments}; @@ -1426,6 +1433,7 @@ sub code_gen { my $need_block = 0; my $arg_offset = $offset; + my $has_gen_dest = 0; @args = map { s/[?]$//g; $_ } @args; foreach (@args) { my($this_size) = $arg_size{$_}; @@ -1436,6 +1444,7 @@ sub code_gen { "Eterm* dst_ptr = REG_TARGET_PTR(dst);\n"; push(@f, "*dst_ptr"); $this_size = $1; + $has_gen_dest = 1; last SWITCH; }; /^packed:[a-zA-z]:(\d):(.*)/ and do { @@ -1468,6 +1477,7 @@ sub code_gen { $var_decls .= "Eterm dst = " . arg_offset($arg_offset) . ";\n" . "Eterm* dst_ptr = REG_TARGET_PTR(dst);\n"; push(@f, "*dst_ptr"); + $has_gen_dest = 1; last SWITCH; }; defined $arg_size{$_} and do { @@ -1482,10 +1492,10 @@ sub code_gen { } # - # If the implementation is in beam_emu.c, there is nothing - # more to do. + # If the implementation is in beam_emu.c or if + # the caller only wants the size, we are done. # - unless (defined $c_code_ref) { + if (not defined $c_code_ref or $params{size_only}) { return ($size+1, undef, ''); } @@ -1550,9 +1560,36 @@ sub code_gen { "{", "$var_decls$body", "}", ""); + + # Make sure that $REFRESH_GEN_DEST() is used when a + # general destination ('d') may have been clobbered by + # a GC. + my $gc_error = verify_gc_code($code, $has_gen_dest); + if (defined $gc_error) { + warn $gc_error; + error("... from the body of $name at $where"); + } + + # Done. ($size+1, $code, $pack_spec); } +sub verify_gc_code { + my $code = shift; + my $has_gen_dest = shift; + + return unless $has_gen_dest; + + if ($code =~ /$GC_REGEXP/o) { + my $code_after_gc = substr($code, $+[0]); + unless ($code_after_gc =~ /dst_ptr = REG_TARGET_PTR/) { + return "pointer to destination register is invalid after GC -- " . + "use \$REFRESH_GEN_DEST()\n"; + } + } + return undef; +} + sub arg_offset { my $offset = shift; "I[" . ($offset+1) . "]"; @@ -1668,8 +1705,11 @@ sub expand_macro { } my $part = $bool ? 'IfTrue' : 'IfFalse'; $body = $new_bindings{$part}; + } elsif ($name eq 'REFRESH_GEN_DEST') { + $body = "dst_ptr = REG_TARGET_PTR(dst)"; } + # Wrap body if needed and return result. $body = "do {\n$body\n} while (0)" if needs_do_wrapper($body); |