perlasm/x86_64-xlate.pl: refine sign extension in ea package.

$1<<32>>32 worked fine with either 32- or 64-bit perl for a good while,
relying on quirk that [pure] 32-bit perl performed it as $1<<0>>0. But
this apparently changed in some version past minimally required 5.10,
and operation result became 0. Yet, it went unnoticed for another while,
because most perl package providers configure their packages with
-Duse64bitint option.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from commit 82e089308bd9a7794a45f0fa3973d7659420fbd8)

diff --git a/crypto/perlasm/x86_64-xlate.pl b/crypto/perlasm/x86_64-xlate.pl
index 7a3dd04b0f9d7f1a0a3c649b917391751f908582..b7ae40b4dbfa98b3c1ef196d302f90dffa3380a2 100755 (executable)
--- a/crypto/perlasm/x86_64-xlate.pl
+++ b/crypto/perlasm/x86_64-xlate.pl
@@ -250,11 +250,18 @@ my %globals;
        $self->{base}  =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
 
        # Solaris /usr/ccs/bin/as can't handle multiplications
-       # in $self->{label}, new gas requires sign extension...
+       # in $self->{label}...
        use integer;
        $self->{label} =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi;
        $self->{label} =~ s/\b([0-9]+\s*[\*\/\%]\s*[0-9]+)\b/eval($1)/eg;
-       $self->{label} =~ s/\b([0-9]+)\b/$1<<32>>32/eg;
+
+       # Some assemblers insist on signed presentation of 32-bit
+       # offsets, but sign extension is a tricky business in perl...
+       if ((1<<31)<<1) {
+           $self->{label} =~ s/\b([0-9]+)\b/$1<<32>>32/eg;
+       } else {
+           $self->{label} =~ s/\b([0-9]+)\b/$1>>0/eg;
+       }
 
        if (!$self->{label} && $self->{index} && $self->{scale}==1 &&
            $self->{base} =~ /(rbp|r13)/) {