Always use adr with __thumb2__.

Thumb2 addresses are a bit a mess, depending on whether a label is
interpreted as a function pointer value (for use with BX and BLX) or as
a program counter value (for use with PC-relative addressing). Clang's
integrated assembler mis-assembles this code. See
https://crbug.com/124610#c54 for details.

Instead, use the ADR pseudo-instruction which has clear semantics and
should be supported by every assembler that handles the OpenSSL Thumb2
code. (In other files, the ADR vs SUB conditionals are based on
__thumb2__ already. For some reason, this one is based on __APPLE__, I'm
guessing to deal with an older version of clang assembler.)

It's unclear to me which of clang or binutils is "correct" or if this is
even a well-defined notion beyond "whatever binutils does". But I will
note that https://github.com/openssl/openssl/pull/4669 suggests binutils
has also changed behavior around this before.

Reviewed-by: Andy Polyakov <appro@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5431)

diff --git a/crypto/aes/asm/aes-armv4.pl b/crypto/aes/asm/aes-armv4.pl
index c6474b8aadcd46b35a9dade3e0cedd8feb48774b..2fa075514a79ada7752eac42b68160006c5e050c 100644 (file)
--- a/crypto/aes/asm/aes-armv4.pl
+++ b/crypto/aes/asm/aes-armv4.pl
@@ -203,7 +203,7 @@ AES_encrypt:
        adr     r3,.
 #endif
        stmdb   sp!,{r1,r4-r12,lr}
-#ifdef __APPLE__
+#if defined(__thumb2__) || defined(__APPLE__)
        adr     $tbl,AES_Te
 #else
        sub     $tbl,r3,#AES_encrypt-AES_Te     @ Te
@@ -481,7 +481,7 @@ _armv4_AES_set_encrypt_key:
        mov     lr,r1                   @ bits
        mov     $key,r2                 @ key
 
-#ifdef __APPLE__
+#if defined(__thumb2__) || defined(__APPLE__)
        adr     $tbl,AES_Te+1024                                @ Te4
 #else
        sub     $tbl,r3,#_armv4_AES_set_encrypt_key-AES_Te-1024 @ Te4
@@ -979,7 +979,7 @@ AES_decrypt:
        adr     r3,.
 #endif
        stmdb   sp!,{r1,r4-r12,lr}
-#ifdef __APPLE__
+#if defined(__thumb2__) || defined(__APPLE__)
        adr     $tbl,AES_Td
 #else
        sub     $tbl,r3,#AES_decrypt-AES_Td     @ Td

diff --git a/crypto/aes/asm/bsaes-armv7.pl b/crypto/aes/asm/bsaes-armv7.pl
index 0c5e762ac2228cfbf7d000400915d0efe128ec7a..8a5f3f1bed14e6fd5aa918532c76b36bb53bde5d 100644 (file)
--- a/crypto/aes/asm/bsaes-armv7.pl
+++ b/crypto/aes/asm/bsaes-armv7.pl
@@ -742,7 +742,7 @@ $code.=<<___;
 _bsaes_decrypt8:
        adr     $const,.
        vldmia  $key!, {@XMM[9]}                @ round 0 key
-#ifdef __APPLE__
+#if defined(__thumb2__) || defined(__APPLE__)
        adr     $const,.LM0ISR
 #else
        add     $const,$const,#.LM0ISR-_bsaes_decrypt8
@@ -841,7 +841,7 @@ _bsaes_const:
 _bsaes_encrypt8:
        adr     $const,.
        vldmia  $key!, {@XMM[9]}                @ round 0 key
-#ifdef __APPLE__
+#if defined(__thumb2__) || defined(__APPLE__)
        adr     $const,.LM0SR
 #else
        sub     $const,$const,#_bsaes_encrypt8-.LM0SR
@@ -949,7 +949,7 @@ $code.=<<___;
 _bsaes_key_convert:
        adr     $const,.
        vld1.8  {@XMM[7]},  [$inp]!             @ load round 0 key
-#ifdef __APPLE__
+#if defined(__thumb2__) || defined(__APPLE__)
        adr     $const,.LM0
 #else
        sub     $const,$const,#_bsaes_key_convert-.LM0