From 5182befa492f4d1cf7e3c7b278cdeb85170abc9c Mon Sep 17 00:00:00 2001
From: Martin Storsjo <martin@martin.st>
Date: Wed, 19 Mar 2014 16:18:44 +0200
Subject: [PATCH] ads2armasm_ms: Add an ALIGN 4 after ENDP
This makes sure that labels for data symbols directly after
functions get properly 4-byte-aligned (when the source is assembled
in thumb mode).
Previously, if declaring a data symbol directly after a function, the
symbol could end up pointing to the unaligned address (if the total
size of the thumb function didn't end up being a multiple of 4). The
data in the symbol itself ended up aligned, but the symbol pointed to
the preceding unaligned position.
That is, a source file looking like this:
---
...
ENDP
symbol
DCD 0x12345678
---
could end up being assembled into
symbol:
xxxxx2: 0000
xxxxx4: 5678
xxxxx6: 1234
(This doesn't happen if the symbol label is on the same line as the
DCD directive.)
By adding an ALIGN 4 directly after the ENDP we make sure the symbol
itself gets aligned properly.
This isn't an issue with the original, untranslated arm source,
since it only is built in arm mode where all instructions are 4 byte,
and since the gnu assembler automatically adds the padding before the
symbol even in thumb mode.
Change-Id: Iadbeebd656b0197e423e79a12a7d3ef8859cf445
---
build/make/ads2armasm_ms.pl | 1 +
1 file changed, 1 insertion(+)
diff --git a/build/make/ads2armasm_ms.pl b/build/make/ads2armasm_ms.pl
index 95c8084030..61ffe88691 100755
--- a/build/make/ads2armasm_ms.pl
+++ b/build/make/ads2armasm_ms.pl
@@ -32,6 +32,7 @@ while (<STDIN>)
s/ldrneb/ldrbne/i;
s/ldrneh/ldrhne/i;
+ s/(ENDP.*)/$&\n ALIGN 4/;
print;
}
--
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