Silence ARMv8 deprecated IT instruction warnings.
ARMv8 kindly deprecated most of its IT instructions in Thumb mode.
These files are taken from upstream and are used on both ARMv7 and ARMv8
processors. Accordingly, silence the warnings by marking the file as
targetting ARMv7. In other files, they were accidentally silenced anyway
by way of the existing .arch lines.
This can be reproduced by building with the new NDK and passing
-DCMAKE_ASM_FLAGS=-march=armv8-a. Some of our downstream code ends up
passing that to the assembly.
Note this change does not attempt to arrange for ARMv8-A/T32 to get
code which honors the constraints. It only silences the warnings and
continues to give it the same ARMv7-A/Thumb-2 code that backwards
compatibility dictates it continue to run.
Bug: chromium:575886, b/63131949
Change-Id: I24ce0b695942eaac799347922b243353b43ad7df
Reviewed-on: https://boringssl-review.googlesource.com/24166
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/chacha/asm/chacha-armv4.pl b/crypto/chacha/asm/chacha-armv4.pl
index a173939..2a9a7d7 100755
--- a/crypto/chacha/asm/chacha-armv4.pl
+++ b/crypto/chacha/asm/chacha-armv4.pl
@@ -171,6 +171,10 @@
$code.=<<___;
#include <openssl/arm_arch.h>
+@ Silence ARMv8 deprecated IT instruction warnings. This file is used by both
+@ ARMv7 and ARMv8 processors and does not use ARMv8 instructions.
+.arch armv7-a
+
.text
#if defined(__thumb2__) || defined(__clang__)
.syntax unified
diff --git a/crypto/fipsmodule/aes/asm/aes-armv4.pl b/crypto/fipsmodule/aes/asm/aes-armv4.pl
index c34d3dc..466a4ba 100644
--- a/crypto/fipsmodule/aes/asm/aes-armv4.pl
+++ b/crypto/fipsmodule/aes/asm/aes-armv4.pl
@@ -76,6 +76,11 @@
# define __ARM_ARCH__ __LINUX_ARM_ARCH__
#endif
+@ Silence ARMv8 deprecated IT instruction warnings. This file is used by both
+@ ARMv7 and ARMv8 processors and does not use ARMv8 instructions. (ARMv8 AES
+@ instructions are in aesv8-armx.pl.)
+.arch armv7-a
+
.text
#if defined(__thumb2__) && !defined(__APPLE__)
.syntax unified
diff --git a/crypto/fipsmodule/bn/asm/armv4-mont.pl b/crypto/fipsmodule/bn/asm/armv4-mont.pl
index c2020cc..094e3b6 100644
--- a/crypto/fipsmodule/bn/asm/armv4-mont.pl
+++ b/crypto/fipsmodule/bn/asm/armv4-mont.pl
@@ -97,6 +97,10 @@
$code=<<___;
#include <openssl/arm_arch.h>
+@ Silence ARMv8 deprecated IT instruction warnings. This file is used by both
+@ ARMv7 and ARMv8 processors and does not use ARMv8 instructions.
+.arch armv7-a
+
.text
#if defined(__thumb2__)
.syntax unified
diff --git a/crypto/fipsmodule/modes/asm/ghash-armv4.pl b/crypto/fipsmodule/modes/asm/ghash-armv4.pl
index e0b4ee0..e93e5b3 100644
--- a/crypto/fipsmodule/modes/asm/ghash-armv4.pl
+++ b/crypto/fipsmodule/modes/asm/ghash-armv4.pl
@@ -142,6 +142,11 @@
$code=<<___;
#include <openssl/arm_arch.h>
+@ Silence ARMv8 deprecated IT instruction warnings. This file is used by both
+@ ARMv7 and ARMv8 processors and does not use ARMv8 instructions. (ARMv8 PMULL
+@ instructions are in aesv8-armx.pl.)
+.arch armv7-a
+
.text
#if defined(__thumb2__) || defined(__clang__)
.syntax unified
diff --git a/crypto/fipsmodule/sha/asm/sha256-armv4.pl b/crypto/fipsmodule/sha/asm/sha256-armv4.pl
index 3eea080..e5ecdfd 100644
--- a/crypto/fipsmodule/sha/asm/sha256-armv4.pl
+++ b/crypto/fipsmodule/sha/asm/sha256-armv4.pl
@@ -181,6 +181,11 @@
# define __ARM_MAX_ARCH__ 7
#endif
+@ Silence ARMv8 deprecated IT instruction warnings. This file is used by both
+@ ARMv7 and ARMv8 processors. It does have ARMv8-only code, but those
+@ instructions are manually-encoded. (See unsha256.)
+.arch armv7-a
+
.text
#if defined(__thumb2__)
.syntax unified
diff --git a/crypto/fipsmodule/sha/asm/sha512-armv4.pl b/crypto/fipsmodule/sha/asm/sha512-armv4.pl
index 85f403e..cc247a4 100644
--- a/crypto/fipsmodule/sha/asm/sha512-armv4.pl
+++ b/crypto/fipsmodule/sha/asm/sha512-armv4.pl
@@ -208,6 +208,10 @@
# define VFP_ABI_POP
#endif
+@ Silence ARMv8 deprecated IT instruction warnings. This file is used by both
+@ ARMv7 and ARMv8 processors and does not use ARMv8 instructions.
+.arch armv7-a
+
#ifdef __ARMEL__
# define LO 0
# define HI 4
