On Mon, 24 Mar 2014, Janne Grunau wrote:

On 2014-03-24 14:38:11 +0200, Martin Storsjö wrote:
A branch instruction in thumb mode might either be narrow or
wide, depending on the offset to the branch location.

armasm seems to have a bug when calculating the difference
between two symbols, where there's such a branch inbetween.
If the branch immediately seems to require a wide instruction,
the symbol difference is calculated properly, but if the
branch is made wide as a consequence from another branch
being made wide, the symbol difference isn't calculated
properly.
---
 gas-preprocessor.pl | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/gas-preprocessor.pl b/gas-preprocessor.pl
index 42e1c7f..16e91ab 100755
--- a/gas-preprocessor.pl
+++ b/gas-preprocessor.pl
@@ -837,15 +837,18 @@ sub handle_serialized_line {


         # Check branch instructions
-        if ($line =~ /(?:^|\n)\s*((\w+\s*:\s*)?bl?x?(..)?(?:\.w)?)\s+(\w+)/) {
+        if ($line =~ /(?:^|\n)\s*(\w+\s*:\s*)?(bl?x?(..)?(\.w)?)\s+(\w+)/) {
+            my $instr = $2;
             my $cond = $3;
-            my $target = $4;
+            my $width = $4;
+            my $target = $5;
             # Don't interpret e.g. bic as b<cc> with ic as conditional code
             if ($cond !~ /|$arm_cond_codes/) {
                 # Not actually a branch
             } elsif ($target =~ /(\d+)([bf])/) {
                 # The target is a local label
                 $line = handle_local_label($line, $1, $2);
+                $line =~ s/\b$instr\b/$&.w/ if $width eq "";

is there a reason not to add 'and $as_type eq "armasm"' to the if?

All of this is within the large armasm translation if block anyway.

// Martin
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