* [PATCH 0/8] Implement assembly cortex-M PACBTI functionality
@ 2022-07-05 13:58 Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 1/8] newlib: libc: define M-profile PACBTI-enablement macros Victor Do Nascimento
` (7 more replies)
0 siblings, 8 replies; 12+ messages in thread
From: Victor Do Nascimento @ 2022-07-05 13:58 UTC (permalink / raw)
To: newlib
This patch series modifies hand-written assembly files for Arm targets,
conditionally enabling branch target identification as well as address
return signature and verification based on Armv8.1-M Pointer
Authentication [1] using ACLE feature test macros at compile-time [2].
Function prologues/epilogues reflect gcc compilation behaviour when
gcc invoked with the following flags:
"-march=armv8.1-m.main -mbranch-protection=pac-ret+leaf+bti -mthumb
-mfloat-abi=soft -fasynchronous-unwind-tables -g -O2 -S"
Regression tested on arm-none-eabi with and without MVE extension and
for Newlib and Newlib-nano.
[1]
<https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/armv8-1-m-pointer-authentication-and-branch-target-identification-extension>
[2] <https://developer.arm.com/documentation/101028/0012/5--Feature-test-macros>
Victor Do Nascimento (8):
newlib: libc: define M-profile PACBTI-enablement macros
newlib: libc: strcmp M-profile PACBTI-enablement
newlib: libc: strlen M-profile PACBTI-enablement
newlib: libc: memchr M-profile PACBTI-enablement
newlib: libc: memcpy M-profile PACBTI-enablement
newlib: libc: setjmp/longjmp M-profile PACBTI-enablement
newlib: libc: aeabi_memmove M-profile PACBTI-enablement
newlib: libc: aeabi_memset M-profile PACBTI-enablement
.../libc/machine/arm/aeabi_memmove-thumb2.S | 42 ++++++++++-
newlib/libc/machine/arm/aeabi_memset-thumb2.S | 45 +++++++++++-
newlib/libc/machine/arm/memchr.S | 49 +++++++++++--
newlib/libc/machine/arm/memcpy-armv7m.S | 73 +++++++++++++++++--
newlib/libc/machine/arm/pacbti.h | 58 +++++++++++++++
newlib/libc/machine/arm/setjmp.S | 32 +++++++-
newlib/libc/machine/arm/strcmp-arm-tiny.S | 7 +-
newlib/libc/machine/arm/strcmp-armv7.S | 45 +++++++++---
newlib/libc/machine/arm/strcmp-armv7m.S | 36 +++++++--
newlib/libc/machine/arm/strlen-armv7.S | 52 ++++++++++++-
newlib/libc/machine/arm/strlen-stub.c | 9 +++
newlib/libc/machine/arm/strlen-thumb2-Os.S | 13 +++-
12 files changed, 417 insertions(+), 44 deletions(-)
create mode 100644 newlib/libc/machine/arm/pacbti.h
--
2.36.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 1/8] newlib: libc: define M-profile PACBTI-enablement macros
2022-07-05 13:58 [PATCH 0/8] Implement assembly cortex-M PACBTI functionality Victor Do Nascimento
@ 2022-07-05 13:58 ` Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 2/8] newlib: libc: strcmp M-profile PACBTI-enablement Victor Do Nascimento
` (6 subsequent siblings)
7 siblings, 0 replies; 12+ messages in thread
From: Victor Do Nascimento @ 2022-07-05 13:58 UTC (permalink / raw)
To: newlib
Create an assembly header file that conditionally defines fuction
prologues/epilogues depending on the compile-time mbranch-protection
argument values.
* newlib/libc/machine/arm/pacbti.h: New.
---
newlib/libc/machine/arm/pacbti.h | 58 ++++++++++++++++++++++++++++++++
1 file changed, 58 insertions(+)
create mode 100644 newlib/libc/machine/arm/pacbti.h
diff --git a/newlib/libc/machine/arm/pacbti.h b/newlib/libc/machine/arm/pacbti.h
new file mode 100644
index 000000000..9921af7bf
--- /dev/null
+++ b/newlib/libc/machine/arm/pacbti.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2022 Arm Ltd
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the company may not be used to endorse or promote
+ * products derived from this software without specific prior written
+ * permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/* Macro to handle function entry depending on branch-protection
+ schemes */
+ .macro pacbti_prologue
+
+#if __ARM_FEATURE_PAC_DEFAULT
+#if __ARM_FEATURE_BTI_DEFAULT
+ pacbti ip, lr, sp
+#else
+ pac ip, lr, sp
+#endif /* __ARM_FEATURE_BTI_DEFAULT */
+ str ip, [sp, #-4]!
+ .save {ra_auth_code}
+ .cfi_def_cfa_offset 4
+ .cfi_offset 143, -4
+#elif __ARM_FEATURE_BTI_DEFAULT
+ bti
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ .endm
+
+/* Macro to handle different branch exchange cases depending on
+ branch-protection schemes */
+ .macro pacbti_epilogue
+#if __ARM_FEATURE_PAC_DEFAULT
+ ldr ip, [sp], #4
+ .cfi_restore 143
+ .cfi_def_cfa_offset 0
+ aut ip, lr, sp
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ bx lr
+ .endm
--
2.36.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 2/8] newlib: libc: strcmp M-profile PACBTI-enablement
2022-07-05 13:58 [PATCH 0/8] Implement assembly cortex-M PACBTI functionality Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 1/8] newlib: libc: define M-profile PACBTI-enablement macros Victor Do Nascimento
@ 2022-07-05 13:58 ` Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 3/8] newlib: libc: strlen " Victor Do Nascimento
` (5 subsequent siblings)
7 siblings, 0 replies; 12+ messages in thread
From: Victor Do Nascimento @ 2022-07-05 13:58 UTC (permalink / raw)
To: newlib
Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.
This patch enables PACBTI for all relevant variants of strcmp:
* Newlib for armv8.1-m.main+pacbti
* Newlib for armv8.1-m.main+pacbti+mve
* Newlib-nano
---
newlib/libc/machine/arm/strcmp-arm-tiny.S | 7 +++-
newlib/libc/machine/arm/strcmp-armv7.S | 45 +++++++++++++++++------
newlib/libc/machine/arm/strcmp-armv7m.S | 36 +++++++++++++++---
3 files changed, 71 insertions(+), 17 deletions(-)
diff --git a/newlib/libc/machine/arm/strcmp-arm-tiny.S b/newlib/libc/machine/arm/strcmp-arm-tiny.S
index 607a41daf..8085eb4df 100644
--- a/newlib/libc/machine/arm/strcmp-arm-tiny.S
+++ b/newlib/libc/machine/arm/strcmp-arm-tiny.S
@@ -29,10 +29,14 @@
/* Tiny version of strcmp in ARM state. Used only when optimizing
for size. Also supports Thumb-2. */
+#include "pacbti.h"
+
.syntax unified
def_fn strcmp
+ .fnstart
.cfi_sections .debug_frame
.cfi_startproc
+ pacbti_prologue
1:
ldrb r2, [r0], #1
ldrb r3, [r1], #1
@@ -42,6 +46,7 @@ def_fn strcmp
beq 1b
2:
subs r0, r2, r3
- bx lr
+ pacbti_epilogue
.cfi_endproc
+ .fnend
.size strcmp, . - strcmp
diff --git a/newlib/libc/machine/arm/strcmp-armv7.S b/newlib/libc/machine/arm/strcmp-armv7.S
index 2f93bfb73..466db3fc8 100644
--- a/newlib/libc/machine/arm/strcmp-armv7.S
+++ b/newlib/libc/machine/arm/strcmp-armv7.S
@@ -45,6 +45,8 @@
.thumb
.syntax unified
+#include "pacbti.h"
+
/* Parameters and result. */
#define src1 r0
#define src2 r1
@@ -91,8 +93,9 @@
ldrd r4, r5, [sp], #16
.cfi_restore 4
.cfi_restore 5
+ .cfi_adjust_cfa_offset -16
sub result, result, r1, lsr #24
- bx lr
+ pacbti_epilogue
#else
/* To use the big-endian trick we'd have to reverse all three words.
that's slower than this approach. */
@@ -112,22 +115,28 @@
ldrd r4, r5, [sp], #16
.cfi_restore 4
.cfi_restore 5
+ .cfi_adjust_cfa_offset -16
sub result, result, r1
- bx lr
+ pacbti_epilogue
#endif
.endm
+
.text
.p2align 5
+ .fnstart
+ .cfi_sections .debug_frame
+ .cfi_startproc
.Lstrcmp_start_addr:
#ifndef STRCMP_NO_PRECHECK
.Lfastpath_exit:
sub r0, r2, r3
- bx lr
+ pacbti_epilogue
nop
#endif
def_fn strcmp
+ pacbti_prologue
#ifndef STRCMP_NO_PRECHECK
ldrb r2, [src1]
ldrb r3, [src2]
@@ -136,16 +145,26 @@ def_fn strcmp
cmpcs r2, r3
bne .Lfastpath_exit
#endif
- .cfi_sections .debug_frame
- .cfi_startproc
strd r4, r5, [sp, #-16]!
- .cfi_def_cfa_offset 16
+ .save {r4, r5}
+ .cfi_adjust_cfa_offset 16
+#ifdef __ARM_FEATURE_PAC_DEFAULT
+ .cfi_offset 4, -20
+ .cfi_offset 5, -16
+#else
.cfi_offset 4, -16
.cfi_offset 5, -12
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
orr tmp1, src1, src2
strd r6, r7, [sp, #8]
+ .save {r6, r7}
+#ifdef __ARM_FEATURE_PAC_DEFAULT
+ .cfi_offset 6, -12
+ .cfi_offset 7, -8
+#else
.cfi_offset 6, -8
.cfi_offset 7, -4
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
mvn const_m1, #0
lsl r2, tmp1, #29
cbz r2, .Lloop_aligned8
@@ -270,7 +289,6 @@ def_fn strcmp
ldr data1, [src1], #4
beq .Laligned_m2
bcs .Laligned_m1
-
#ifdef STRCMP_NO_PRECHECK
ldrb data2, [src2, #1]
uxtb tmp1, data1, ror #BYTE1_OFFSET
@@ -314,7 +332,8 @@ def_fn strcmp
mov result, tmp1
ldr r4, [sp], #16
.cfi_restore 4
- bx lr
+ .cfi_adjust_cfa_offset -16
+ pacbti_epilogue
#ifndef STRCMP_NO_PRECHECK
.Laligned_m1:
@@ -364,8 +383,9 @@ def_fn strcmp
/* R6/7 Not used in this sequence. */
.cfi_restore 6
.cfi_restore 7
+ .cfi_adjust_cfa_offset -16
neg result, result
- bx lr
+ pacbti_epilogue
6:
.cfi_restore_state
@@ -441,7 +461,8 @@ def_fn strcmp
/* R6/7 not used in this sequence. */
.cfi_restore 6
.cfi_restore 7
- bx lr
+ .cfi_adjust_cfa_offset -16
+ pacbti_epilogue
.Lstrcmp_tail:
.cfi_restore_state
@@ -463,7 +484,9 @@ def_fn strcmp
/* R6/7 not used in this sequence. */
.cfi_restore 6
.cfi_restore 7
+ .cfi_adjust_cfa_offset -16
sub result, result, data2, lsr #24
- bx lr
+ pacbti_epilogue
.cfi_endproc
+ .fnend
.size strcmp, . - .Lstrcmp_start_addr
diff --git a/newlib/libc/machine/arm/strcmp-armv7m.S b/newlib/libc/machine/arm/strcmp-armv7m.S
index cdb4912df..4bbc63ba8 100644
--- a/newlib/libc/machine/arm/strcmp-armv7m.S
+++ b/newlib/libc/machine/arm/strcmp-armv7m.S
@@ -29,6 +29,8 @@
/* Very similar to the generic code, but uses Thumb2 as implemented
in ARMv7-M. */
+#include "pacbti.h"
+
/* Parameters and result. */
#define src1 r0
#define src2 r1
@@ -44,8 +46,10 @@
.thumb
.syntax unified
def_fn strcmp
+ .fnstart
.cfi_sections .debug_frame
.cfi_startproc
+ pacbti_prologue
eor tmp1, src1, src2
tst tmp1, #3
/* Strings not at same byte offset from a word boundary. */
@@ -106,7 +110,7 @@ def_fn strcmp
lsrs result, result, #24
subs result, result, data2
#endif
- bx lr
+ pacbti_epilogue
#if 0
@@ -214,12 +218,18 @@ def_fn strcmp
cmpcs data1, data2
beq .Lstrcmp_unaligned
sub result, data1, data2
- bx lr
+ pacbti_epilogue
2:
stmfd sp!, {r5}
- .cfi_def_cfa_offset 4
+ .save {r5}
+ .cfi_adjust_cfa_offset 4
+#ifdef __ARM_FEATURE_PAC_DEFAULT
+ .cfi_offset 5, -8 /* Account for ip register already on stack */
+#else
.cfi_offset 5, -4
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+
ldr data1, [src1], #4
and tmp2, src2, #3
@@ -353,10 +363,17 @@ def_fn strcmp
.Lstrcmp_done_equal:
mov result, #0
.cfi_remember_state
+#ifdef __ARM_FEATURE_PAC_DEFAULT
+ pop {r5, ip}
+ .cfi_restore 5
+ .cfi_restore 142
+ aut ip, lr, sp
+#else
ldmfd sp!, {r5}
.cfi_restore 5
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
.cfi_def_cfa_offset 0
- bx lr
+ bx lr
.Lstrcmp_tail:
.cfi_restore_state
@@ -370,9 +387,18 @@ def_fn strcmp
S2LOEQ data2, data2, #8
beq .Lstrcmp_tail
sub result, r2, result
+#ifdef __ARM_FEATURE_PAC_DEFAULT
+ pop {r5, ip}
+ .cfi_restore 5
+ .cfi_restore 142
+ .cfi_def_cfa_offset 0
+ aut ip, lr, sp
+#else
ldmfd sp!, {r5}
.cfi_restore 5
.cfi_def_cfa_offset 0
- bx lr
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ bx lr
.cfi_endproc
+ .fnend
.size strcmp, . - strcmp
--
2.36.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 3/8] newlib: libc: strlen M-profile PACBTI-enablement
2022-07-05 13:58 [PATCH 0/8] Implement assembly cortex-M PACBTI functionality Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 1/8] newlib: libc: define M-profile PACBTI-enablement macros Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 2/8] newlib: libc: strcmp M-profile PACBTI-enablement Victor Do Nascimento
@ 2022-07-05 13:58 ` Victor Do Nascimento
2022-07-05 15:39 ` Richard Earnshaw
2022-07-05 13:58 ` [PATCH 4/8] newlib: libc: memchr " Victor Do Nascimento
` (4 subsequent siblings)
7 siblings, 1 reply; 12+ messages in thread
From: Victor Do Nascimento @ 2022-07-05 13:58 UTC (permalink / raw)
To: newlib
Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.
This patch enables PACBTI for all relevant variants of strlen:
* Newlib for armv8.1-m.main+pacbti
* Newlib for armv8.1-m.main+pacbti+mve
* Newlib-nano
---
newlib/libc/machine/arm/strlen-armv7.S | 52 ++++++++++++++++++++--
newlib/libc/machine/arm/strlen-stub.c | 9 ++++
newlib/libc/machine/arm/strlen-thumb2-Os.S | 13 ++++--
3 files changed, 67 insertions(+), 7 deletions(-)
diff --git a/newlib/libc/machine/arm/strlen-armv7.S b/newlib/libc/machine/arm/strlen-armv7.S
index f3dda0d60..18c8226d0 100644
--- a/newlib/libc/machine/arm/strlen-armv7.S
+++ b/newlib/libc/machine/arm/strlen-armv7.S
@@ -59,6 +59,7 @@
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
#include "acle-compat.h"
+#include "pacbti.h"
.macro def_fn f p2align=0
.text
@@ -77,7 +78,9 @@
#endif
/* This code requires Thumb. */
-#if __ARM_ARCH_PROFILE == 'M'
+#if __ARM_ARCH_8M_MAIN__
+ /* keep config inherited from -march= */
+#elif __ARM_ARCH_PROFILE == 'M'
.arch armv7e-m
#else
.arch armv6t2
@@ -100,8 +103,34 @@
#define tmp2 r5
def_fn strlen p2align=6
+ .fnstart
+ .cfi_startproc
+ /* common pacbti_prologue macro from pacbti.h not used.
+ handwritten prologue saves one push instruction. */
+#if __ARM_FEATURE_PAC_DEFAULT
+#if __ARM_FEATURE_BTI_DEFAULT
+ pacbti ip, lr, sp
+#else
+ pac ip, lr, sp
+#endif /* __ARM_FEATURE_BTI_DEFAULT */
+ push {r4, r5, ip}
+ .save {r4, r5, ra_auth_code}
+ .cfi_def_cfa_offset 12
+ .cfi_offset 143, -4
+ .cfi_offset 5, -8
+ .cfi_offset 4, -12
+
+#else
+#if __ARM_FEATURE_BTI_DEFAULT
+ bti
+#endif /* __ARM_FEATURE_BTI_DEFAULT */
+ push {r4, r5}
+ .save {r4, r5}
+ .cfi_def_cfa_offset 8
+ .cfi_offset 5, -4
+ .cfi_offset 4, -8
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
pld [srcin, #0]
- strd r4, r5, [sp, #-8]!
bic src, srcin, #7
mvn const_m1, #0
ands tmp1, srcin, #7 /* (8 - bytes) to alignment. */
@@ -159,9 +188,22 @@ def_fn strlen p2align=6
rev data1a, data1a
#endif
clz data1a, data1a
- ldrd r4, r5, [sp], #8
add result, result, data1a, lsr #3 /* Bits -> Bytes. */
- bx lr
+#if __ARM_FEATURE_PAC_DEFAULT
+ pop {r4, r5, ip}
+ .cfi_restore 4
+ .cfi_restore 5
+ .cfi_restore 143
+ .cfi_def_cfa_offset 0
+ aut ip, lr, sp
+#else
+ ldrd r4, r5, [sp], #8
+ .cfi_restore 4
+ .cfi_restore 5
+ .cfi_def_cfa_offset 0
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ bx lr
+
.Lmisaligned8:
ldrd data1a, data1b, [src]
@@ -177,4 +219,6 @@ def_fn strlen p2align=6
movne data1a, const_m1
mov const_0, #0
b .Lstart_realigned
+ .cfi_endproc
+ .fnend
.size strlen, . - strlen
diff --git a/newlib/libc/machine/arm/strlen-stub.c b/newlib/libc/machine/arm/strlen-stub.c
index fc2daf16f..4a0bb8cbb 100644
--- a/newlib/libc/machine/arm/strlen-stub.c
+++ b/newlib/libc/machine/arm/strlen-stub.c
@@ -58,6 +58,11 @@ strlen (const char* str)
"data .req r3\n\t"
"addr .req r1\n\t"
+#ifdef __ARM_FEATURE_PAC_DEFAULT
+ "pac ip, lr, sp\n\t"
+ "str ip, [sp, #-4]!\n\t"
+#endif
+
#ifdef _ISA_ARM_7
"pld [r0]\n\t"
#endif
@@ -167,6 +172,10 @@ strlen (const char* str)
"it ne\n\t"
"addne len, len, #1\n\t"
# endif
+#endif
+#ifdef __ARM_FEATURE_PAC_DEFAULT
+ "ldr ip, [sp], #4\n\t"
+ "aut ip, lr, sp\n\t"
#endif
"bx lr\n\t");
}
diff --git a/newlib/libc/machine/arm/strlen-thumb2-Os.S b/newlib/libc/machine/arm/strlen-thumb2-Os.S
index 961f41a0a..823b0310e 100644
--- a/newlib/libc/machine/arm/strlen-thumb2-Os.S
+++ b/newlib/libc/machine/arm/strlen-thumb2-Os.S
@@ -25,6 +25,7 @@
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
#include "acle-compat.h"
+#include "pacbti.h"
.macro def_fn f p2align=0
.text
@@ -33,8 +34,9 @@
.type \f, %function
\f:
.endm
-
-#if __ARM_ARCH_ISA_THUMB >= 2 && __ARM_ARCH >= 7
+#if __ARM_ARCH_8M_MAIN__
+ /* keep config inherited from -march= */
+#elif __ARM_ARCH_ISA_THUMB >= 2 && __ARM_ARCH >= 7
.arch armv7
#else
.arch armv6t2
@@ -44,11 +46,16 @@
.syntax unified
def_fn strlen p2align=1
+ .fnstart
+ .cfi_startproc
+ pacbti_prologue
mov r3, r0
1: ldrb.w r2, [r3], #1
cmp r2, #0
bne 1b
subs r0, r3, r0
subs r0, #1
- bx lr
+ pacbti_epilogue
+ .cfi_endproc
+ .fnend
.size strlen, . - strlen
--
2.36.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 4/8] newlib: libc: memchr M-profile PACBTI-enablement
2022-07-05 13:58 [PATCH 0/8] Implement assembly cortex-M PACBTI functionality Victor Do Nascimento
` (2 preceding siblings ...)
2022-07-05 13:58 ` [PATCH 3/8] newlib: libc: strlen " Victor Do Nascimento
@ 2022-07-05 13:58 ` Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 5/8] newlib: libc: memcpy " Victor Do Nascimento
` (3 subsequent siblings)
7 siblings, 0 replies; 12+ messages in thread
From: Victor Do Nascimento @ 2022-07-05 13:58 UTC (permalink / raw)
To: newlib
Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.
---
newlib/libc/machine/arm/memchr.S | 49 ++++++++++++++++++++++++++++----
1 file changed, 44 insertions(+), 5 deletions(-)
diff --git a/newlib/libc/machine/arm/memchr.S b/newlib/libc/machine/arm/memchr.S
index 1a4c6512c..644cfda3f 100644
--- a/newlib/libc/machine/arm/memchr.S
+++ b/newlib/libc/machine/arm/memchr.S
@@ -76,6 +76,7 @@
.syntax unified
#include "acle-compat.h"
+#include "pacbti.h"
@ NOTE: This ifdef MUST match the one in memchr-stub.c
#if defined (__ARM_NEON__) || defined (__ARM_NEON)
@@ -266,7 +267,9 @@ memchr:
#elif __ARM_ARCH_ISA_THUMB >= 2 && defined (__ARM_FEATURE_DSP)
-#if __ARM_ARCH_PROFILE == 'M'
+#if __ARM_ARCH_8M_MAIN__
+ /* keep config inherited from -march= */
+#elif __ARM_ARCH_PROFILE == 'M'
.arch armv7e-m
#else
.arch armv6t2
@@ -287,11 +290,14 @@ memchr:
.p2align 4,,15
.global memchr
.type memchr,%function
+ .fnstart
+ .cfi_startproc
memchr:
@ r0 = start of memory to scan
@ r1 = character to look for
@ r2 = length
@ returns r0 = pointer to character or NULL if not found
+ pacbti_prologue
and r1,r1,#0xff @ Don't trust the caller to pass a char
cmp r2,#16 @ If short don't bother with anything clever
@@ -313,6 +319,19 @@ memchr:
10:
@ We are aligned, we know we have at least 8 bytes to work with
push {r4,r5,r6,r7}
+ .save {r4-r7}
+ .cfi_adjust_cfa_offset 16
+#ifdef __ARM_FEATURE_PAC_DEFAULT
+ .cfi_offset 4, -20
+ .cfi_offset 5, -16
+ .cfi_offset 6, -12
+ .cfi_offset 7, -8
+#else
+ .cfi_offset 4, -16
+ .cfi_offset 5, -12
+ .cfi_offset 6, -8
+ .cfi_offset 7, -4
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
orr r1, r1, r1, lsl #8 @ expand the match word across all bytes
orr r1, r1, r1, lsl #16
bic r4, r2, #7 @ Number of double words to work with * 8
@@ -334,6 +353,11 @@ memchr:
bne 15b @ (Flags from the subs above)
pop {r4,r5,r6,r7}
+ .cfi_restore 7
+ .cfi_restore 6
+ .cfi_restore 5
+ .cfi_restore 4
+ .cfi_adjust_cfa_offset -16
and r1,r1,#0xff @ r1 back to a single character
and r2,r2,#7 @ Leave the count remaining as the number
@ after the double words have been done
@@ -350,11 +374,11 @@ memchr:
40:
movs r0,#0 @ not found
- bx lr
+ pacbti_epilogue
50:
subs r0,r0,#1 @ found
- bx lr
+ pacbti_epilogue
60: @ We're here because the fast path found a hit
@ now we have to track down exactly which word it was
@@ -378,9 +402,24 @@ memchr:
addeq r0,r0,#1
61:
- pop {r4,r5,r6,r7}
subs r0,r0,#1
- bx lr
+#if __ARM_FEATURE_PAC_DEFAULT
+ pop {r4,r5,r6,r7,ip}
+ .cfi_restore 143
+#else
+ pop {r4,r5,r6,r7}
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ .cfi_restore 7
+ .cfi_restore 6
+ .cfi_restore 5
+ .cfi_restore 4
+ .cfi_def_cfa_offset 0
+#if __ARM_FEATURE_PAC_DEFAULT
+ aut ip, lr, sp
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ bx lr
+ .cfi_endproc
+ .fnend
#else
/* Defined in memchr-stub.c. */
#endif
--
2.36.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 5/8] newlib: libc: memcpy M-profile PACBTI-enablement
2022-07-05 13:58 [PATCH 0/8] Implement assembly cortex-M PACBTI functionality Victor Do Nascimento
` (3 preceding siblings ...)
2022-07-05 13:58 ` [PATCH 4/8] newlib: libc: memchr " Victor Do Nascimento
@ 2022-07-05 13:58 ` Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 6/8] newlib: libc: setjmp/longjmp " Victor Do Nascimento
` (2 subsequent siblings)
7 siblings, 0 replies; 12+ messages in thread
From: Victor Do Nascimento @ 2022-07-05 13:58 UTC (permalink / raw)
To: newlib
Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.
---
newlib/libc/machine/arm/memcpy-armv7m.S | 73 ++++++++++++++++++++++---
1 file changed, 65 insertions(+), 8 deletions(-)
diff --git a/newlib/libc/machine/arm/memcpy-armv7m.S b/newlib/libc/machine/arm/memcpy-armv7m.S
index c8bff36f6..cdcca7c9e 100644
--- a/newlib/libc/machine/arm/memcpy-armv7m.S
+++ b/newlib/libc/machine/arm/memcpy-armv7m.S
@@ -46,6 +46,8 @@
__OPT_BIG_BLOCK_SIZE: Size of big block in words. Default to 64.
__OPT_MID_BLOCK_SIZE: Size of big block in words. Default to 16.
*/
+#include "pacbti.h"
+
#ifndef __OPT_BIG_BLOCK_SIZE
#define __OPT_BIG_BLOCK_SIZE (4 * 16)
#endif
@@ -85,6 +87,8 @@
.global memcpy
.thumb
.thumb_func
+ .fnstart
+ .cfi_startproc
.type memcpy, %function
memcpy:
@ r0: dst
@@ -93,10 +97,30 @@ memcpy:
#ifdef __ARM_FEATURE_UNALIGNED
/* In case of UNALIGNED access supported, ip is not used in
function body. */
+ pacbti_prologue
mov ip, r0
#else
+#if __ARM_FEATURE_PAC_DEFAULT
+#if __ARM_FEATURE_BTI_DEFAULT
+ pacbti ip, lr, sp
+#else
+ pac ip, lr, sp
+#endif /* __ARM_FEATURE_BTI_DEFAULT */
+ push {r0, ip}
+ .save {r0, ra_auth_code}
+ .cfi_def_cfa_offset 8
+ .cfi_offset 0, -8
+ .cfi_offset 143, -4
+#else
+#if __ARM_FEATURE_BTI_DEFAULT
+ bti
+#endif /* __ARM_FEATURE_BTI_DEFAULT */
push {r0}
-#endif
+ .save {r0}
+ .cfi_adjust_cfa_offset 4
+ .cfi_offset 0, -4
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+#endif /* __ARM_FEATURE_UNALIGNED */
orr r3, r1, r0
ands r3, r3, #3
bne .Lmisaligned_copy
@@ -135,13 +159,13 @@ memcpy:
ldr r3, [r1], #4
str r3, [r0], #4
END_UNROLL
-#else /* __ARM_ARCH_7M__ */
+#else
ldr r3, [r1, \offset]
str r3, [r0, \offset]
END_UNROLL
adds r0, __OPT_MID_BLOCK_SIZE
adds r1, __OPT_MID_BLOCK_SIZE
-#endif
+#endif /* __ARM_ARCH_7M__ */
subs r2, __OPT_MID_BLOCK_SIZE
bhs .Lmid_block_loop
@@ -180,10 +204,21 @@ memcpy:
.Ldone:
#ifdef __ARM_FEATURE_UNALIGNED
mov r0, ip
+ pacbti_epilogue
+#else
+#if __ARM_FEATURE_PAC_DEFAULT
+ pop {r0, ra_auth_code}
+ .cfi_restore 0
+ .cfi_restore 143
+ .cfi_def_cfa_offset 0
+ aut ip, lr, sp
#else
pop {r0}
-#endif
- bx lr
+ .cfi_restore 0
+ .cfi_def_cfa_offset 0
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ bx lr
+#endif /* __ARM_FEATURE_UNALIGNED */
.align 2
.Lmisaligned_copy:
@@ -247,6 +282,15 @@ memcpy:
/* dst is aligned, but src isn't. Misaligned copy. */
push {r4, r5}
+ .save {r4, r5}
+ .cfi_adjust_cfa_offset 8
+#ifdef __ARM_FEATURE_PAC_DEFAULT /* we pushed just the pac code */
+ .cfi_offset 4, -12
+ .cfi_offset 5, -8
+#else /* we haven't pushed anything to stack */
+ .cfi_offset 4, -8
+ .cfi_offset 5, -4
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
subs r2, #4
/* Backward r1 by misaligned bytes, to make r1 aligned.
@@ -299,6 +343,7 @@ memcpy:
adds r2, #4
subs r1, ip
pop {r4, r5}
+ .cfi_adjust_cfa_offset -8
#endif /* __ARM_FEATURE_UNALIGNED */
@@ -321,9 +366,21 @@ memcpy:
#ifdef __ARM_FEATURE_UNALIGNED
mov r0, ip
+ pacbti_epilogue
+#else
+#if __ARM_FEATURE_PAC_DEFAULT
+ pop {r0, ra_auth_code}
+ .cfi_restore 0
+ .cfi_restore 143
+ .cfi_def_cfa_offset 0
+ aut ip, lr, sp
#else
pop {r0}
-#endif
- bx lr
-
+ .cfi_restore 0
+ .cfi_def_cfa_offset 0
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ bx lr
+#endif /* __ARM_FEATURE_UNALIGNED */
+ .cfi_endproc
+ .fnend
.size memcpy, .-memcpy
--
2.36.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 6/8] newlib: libc: setjmp/longjmp M-profile PACBTI-enablement
2022-07-05 13:58 [PATCH 0/8] Implement assembly cortex-M PACBTI functionality Victor Do Nascimento
` (4 preceding siblings ...)
2022-07-05 13:58 ` [PATCH 5/8] newlib: libc: memcpy " Victor Do Nascimento
@ 2022-07-05 13:58 ` Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 7/8] newlib: libc: aeabi_memmove " Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 8/8] newlib: libc: aeabi_memset " Victor Do Nascimento
7 siblings, 0 replies; 12+ messages in thread
From: Victor Do Nascimento @ 2022-07-05 13:58 UTC (permalink / raw)
To: newlib
Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.
---
newlib/libc/machine/arm/setjmp.S | 32 ++++++++++++++++++++++++++++++--
1 file changed, 30 insertions(+), 2 deletions(-)
diff --git a/newlib/libc/machine/arm/setjmp.S b/newlib/libc/machine/arm/setjmp.S
index 21d6ff9e7..d48e1a69b 100644
--- a/newlib/libc/machine/arm/setjmp.S
+++ b/newlib/libc/machine/arm/setjmp.S
@@ -157,11 +157,15 @@ SYM (.arm_start_of.\name):
.globl SYM (\name)
TYPE (\name)
SYM (\name):
+ .fnstart
+ .cfi_startproc
PROLOGUE \name
.endm
.macro FUNC_END name
RET
+ .cfi_endproc
+ .fnend
SIZE (\name)
.endm
@@ -173,11 +177,25 @@ SYM (\name):
/* Save all the callee-preserved registers into the jump buffer. */
#ifdef __thumb2__
+#if __ARM_FEATURE_PAC_DEFAULT
+#if __ARM_FEATURE_BTI_DEFAULT
+ pacbti ip, lr, sp
+#else
+ pac ip, lr, sp
+#endif /* __ARM_FEATURE_BTI_DEFAULT */
+ mov a4, ip
+ mov ip, sp
+ stmea a1!, { a4, v1-v7, fp, ip, lr }
+#else
+#if __ARM_FEATURE_BTI_DEFAULT
+ bti
+#endif /* __ARM_FEATURE_BTI_DEFAULT */
mov ip, sp
stmea a1!, { v1-v7, fp, ip, lr }
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
#else
stmea a1!, { v1-v7, fp, ip, sp, lr }
-#endif
+#endif /* __thumb2__ */
#if 0 /* Simulator does not cope with FP instructions yet. */
#ifndef __SOFTFP__
@@ -200,11 +218,17 @@ SYM (\name):
/* Restore the registers, retrieving the state when setjmp() was called. */
#ifdef __thumb2__
+#if __ARM_FEATURE_PAC_DEFAULT
+ ldmfd a1!, { a4, v1-v7, fp, ip, lr }
+ mov sp, ip
+ mov ip, a4
+#else
ldmfd a1!, { v1-v7, fp, ip, lr }
mov sp, ip
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
#else
ldmfd a1!, { v1-v7, fp, ip, sp, lr }
-#endif
+#endif /* __thumb2__ */
#if 0 /* Simulator does not cope with FP instructions yet. */
#ifndef __SOFTFP__
@@ -220,5 +244,9 @@ SYM (\name):
#endif
moveq a1, #1
+#if __ARM_FEATURE_PAC_DEFAULT
+ aut ip, lr, sp
+#endif
+
FUNC_END longjmp
#endif
--
2.36.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 7/8] newlib: libc: aeabi_memmove M-profile PACBTI-enablement
2022-07-05 13:58 [PATCH 0/8] Implement assembly cortex-M PACBTI functionality Victor Do Nascimento
` (5 preceding siblings ...)
2022-07-05 13:58 ` [PATCH 6/8] newlib: libc: setjmp/longjmp " Victor Do Nascimento
@ 2022-07-05 13:58 ` Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 8/8] newlib: libc: aeabi_memset " Victor Do Nascimento
7 siblings, 0 replies; 12+ messages in thread
From: Victor Do Nascimento @ 2022-07-05 13:58 UTC (permalink / raw)
To: newlib
Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.
---
.../libc/machine/arm/aeabi_memmove-thumb2.S | 42 +++++++++++++++++--
1 file changed, 38 insertions(+), 4 deletions(-)
diff --git a/newlib/libc/machine/arm/aeabi_memmove-thumb2.S b/newlib/libc/machine/arm/aeabi_memmove-thumb2.S
index e9504437b..237e63cc0 100644
--- a/newlib/libc/machine/arm/aeabi_memmove-thumb2.S
+++ b/newlib/libc/machine/arm/aeabi_memmove-thumb2.S
@@ -26,6 +26,8 @@
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
+ #include "pacbti.h"
+
.thumb
.syntax unified
.global __aeabi_memmove
@@ -33,8 +35,18 @@
ASM_ALIAS __aeabi_memmove4 __aeabi_memmove
ASM_ALIAS __aeabi_memmove8 __aeabi_memmove
__aeabi_memmove:
+ .fnstart
+ .cfi_startproc
+ pacbti_prologue
cmp r0, r1
push {r4}
+ .save {r4}
+ .cfi_adjust_cfa_offset 4
+#if __ARM_FEATURE_PAC_DEFAULT
+ .cfi_offset 4, -8
+#else
+ .cfi_offset 4, -4
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
bls 3f
adds r3, r1, r2
cmp r0, r3
@@ -48,8 +60,18 @@ __aeabi_memmove:
strb r4, [r1, #-1]!
bne 1b
2:
- pop {r4}
- bx lr
+#if __ARM_FEATURE_PAC_DEFAULT
+ pop {r4, ip}
+ .cfi_restore 4
+ .cfi_restore 143
+ .cfi_def_cfa_offset 0
+ aut ip, lr, sp
+#else
+ pop {r4}
+ .cfi_restore 4
+ .cfi_def_cfa_offset 0
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ bx lr
3:
cmp r2, #0
beq 2b
@@ -60,6 +82,18 @@ __aeabi_memmove:
cmp r2, r1
strb r4, [r3, #1]!
bne 4b
- pop {r4}
- bx lr
+#if __ARM_FEATURE_PAC_DEFAULT
+ pop {r4, ip}
+ .cfi_restore 4
+ .cfi_restore 143
+ .cfi_def_cfa_offset 0
+ aut ip, lr, sp
+#else
+ pop {r4}
+ .cfi_restore 4
+ .cfi_def_cfa_offset 0
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+ bx lr
+ .cfi_endproc
+ .fnend
.size __aeabi_memmove, . - __aeabi_memmove
--
2.36.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 8/8] newlib: libc: aeabi_memset M-profile PACBTI-enablement
2022-07-05 13:58 [PATCH 0/8] Implement assembly cortex-M PACBTI functionality Victor Do Nascimento
` (6 preceding siblings ...)
2022-07-05 13:58 ` [PATCH 7/8] newlib: libc: aeabi_memmove " Victor Do Nascimento
@ 2022-07-05 13:58 ` Victor Do Nascimento
7 siblings, 0 replies; 12+ messages in thread
From: Victor Do Nascimento @ 2022-07-05 13:58 UTC (permalink / raw)
To: newlib
Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.
---
newlib/libc/machine/arm/aeabi_memset-thumb2.S | 45 ++++++++++++++++++-
1 file changed, 44 insertions(+), 1 deletion(-)
diff --git a/newlib/libc/machine/arm/aeabi_memset-thumb2.S b/newlib/libc/machine/arm/aeabi_memset-thumb2.S
index eaca1d8d7..a22d4314a 100644
--- a/newlib/libc/machine/arm/aeabi_memset-thumb2.S
+++ b/newlib/libc/machine/arm/aeabi_memset-thumb2.S
@@ -26,14 +26,42 @@
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
+#include "pacbti.h"
+
.thumb
.syntax unified
.global __aeabi_memset
.type __aeabi_memset, %function
+ .fnstart
+ .cfi_startproc
ASM_ALIAS __aeabi_memset4 __aeabi_memset
ASM_ALIAS __aeabi_memset8 __aeabi_memset
__aeabi_memset:
+#if __ARM_FEATURE_PAC_DEFAULT
+#if __ARM_FEATURE_BTI_DEFAULT
+ pacbti ip, lr, sp
+#else
+ pac ip, lr, sp
+#endif /* __ARM_FEATURE_BTI_DEFAULT */
+ push {r4, r5, r6, ip}
+ .save {r4, r5, r6, ra_auth_code}
+ .cfi_def_cfa_offset 16
+ .cfi_offset 4, -16
+ .cfi_offset 5, -12
+ .cfi_offset 6, -8
+ .cfi_offset 143, -4
+#else
+#if __ARM_FEATURE_BTI_DEFAULT
+ bti
+#endif /* __ARM_FEATURE_BTI_DEFAULT */
push {r4, r5, r6}
+ .save {r4, r5, r6}
+ .cfi_def_cfa_offset 12
+ .cfi_offset 4, -12
+ .cfi_offset 5, -8
+ .cfi_offset 6, -4
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
+
lsls r4, r0, #30
beq 10f
subs r4, r1, #1
@@ -98,10 +126,25 @@ __aeabi_memset:
cmp r3, r4
bne 8b
9:
+#if __ARM_FEATURE_PAC_DEFAULT
+ pop {r4, r5, r6, ip}
+ .cfi_restore 143
+ .cfi_restore 6
+ .cfi_restore 5
+ .cfi_restore 4
+ .cfi_def_cfa_offset 0
+ aut ip, lr, sp
+#else
pop {r4, r5, r6}
- bx lr
+ .cfi_restore 6
+ .cfi_restore 5
+ .cfi_restore 4
+ .cfi_def_cfa_offset 0
+#endif /* __ARM_FEATURE_PAC_DEFAULT */
10:
mov r4, r1
mov r3, r0
b 3b
+ .cfi_endproc
+ .fnend
.size __aeabi_memset, . - __aeabi_memset
--
2.36.1
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 3/8] newlib: libc: strlen M-profile PACBTI-enablement
2022-07-05 13:58 ` [PATCH 3/8] newlib: libc: strlen " Victor Do Nascimento
@ 2022-07-05 15:39 ` Richard Earnshaw
2022-07-05 16:30 ` Victor L. Do Nascimento
0 siblings, 1 reply; 12+ messages in thread
From: Richard Earnshaw @ 2022-07-05 15:39 UTC (permalink / raw)
To: Victor Do Nascimento, newlib
On 05/07/2022 14:58, Victor Do Nascimento wrote:
> Add function prologue/epilogue to conditionally add BTI landing pads
> and/or PAC code generation & authentication instructions depending on
> compilation flags.
>
> This patch enables PACBTI for all relevant variants of strlen:
> * Newlib for armv8.1-m.main+pacbti
> * Newlib for armv8.1-m.main+pacbti+mve
> * Newlib-nano
> ---
> newlib/libc/machine/arm/strlen-armv7.S | 52 ++++++++++++++++++++--
> newlib/libc/machine/arm/strlen-stub.c | 9 ++++
> newlib/libc/machine/arm/strlen-thumb2-Os.S | 13 ++++--
> 3 files changed, 67 insertions(+), 7 deletions(-)
>
> diff --git a/newlib/libc/machine/arm/strlen-armv7.S b/newlib/libc/machine/arm/strlen-armv7.S
> index f3dda0d60..18c8226d0 100644
> --- a/newlib/libc/machine/arm/strlen-armv7.S
> +++ b/newlib/libc/machine/arm/strlen-armv7.S
> @@ -59,6 +59,7 @@
> OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
>
> #include "acle-compat.h"
> +#include "pacbti.h"
>
> .macro def_fn f p2align=0
> .text
> @@ -77,7 +78,9 @@
> #endif
>
> /* This code requires Thumb. */
> -#if __ARM_ARCH_PROFILE == 'M'
> +#if __ARM_ARCH_8M_MAIN__
These GCC architecture macros (those that end with '__') aren't portable
and are essentially deprecated. What exactly are you trying to achieve
here?
> + /* keep config inherited from -march= */
> +#elif __ARM_ARCH_PROFILE == 'M'
> .arch armv7e-m
> #else
> .arch armv6t2
> @@ -100,8 +103,34 @@
> #define tmp2 r5
>
> def_fn strlen p2align=6
> + .fnstart
> + .cfi_startproc
> + /* common pacbti_prologue macro from pacbti.h not used.
> + handwritten prologue saves one push instruction. */
> +#if __ARM_FEATURE_PAC_DEFAULT
> +#if __ARM_FEATURE_BTI_DEFAULT
> + pacbti ip, lr, sp
> +#else
> + pac ip, lr, sp
> +#endif /* __ARM_FEATURE_BTI_DEFAULT */
> + push {r4, r5, ip}
> + .save {r4, r5, ra_auth_code}
> + .cfi_def_cfa_offset 12
> + .cfi_offset 143, -4
> + .cfi_offset 5, -8
> + .cfi_offset 4, -12
> +
> +#else
> +#if __ARM_FEATURE_BTI_DEFAULT
> + bti
> +#endif /* __ARM_FEATURE_BTI_DEFAULT */
> + push {r4, r5}
> + .save {r4, r5}
> + .cfi_def_cfa_offset 8
> + .cfi_offset 5, -4
> + .cfi_offset 4, -8
> +#endif /* __ARM_FEATURE_PAC_DEFAULT */
> pld [srcin, #0]
> - strd r4, r5, [sp, #-8]!
> bic src, srcin, #7
> mvn const_m1, #0
> ands tmp1, srcin, #7 /* (8 - bytes) to alignment. */
> @@ -159,9 +188,22 @@ def_fn strlen p2align=6
> rev data1a, data1a
> #endif
> clz data1a, data1a
> - ldrd r4, r5, [sp], #8
> add result, result, data1a, lsr #3 /* Bits -> Bytes. */
> - bx lr
> +#if __ARM_FEATURE_PAC_DEFAULT
> + pop {r4, r5, ip}
> + .cfi_restore 4
> + .cfi_restore 5
> + .cfi_restore 143
> + .cfi_def_cfa_offset 0
> + aut ip, lr, sp
> +#else
> + ldrd r4, r5, [sp], #8
> + .cfi_restore 4
> + .cfi_restore 5
> + .cfi_def_cfa_offset 0
> +#endif /* __ARM_FEATURE_PAC_DEFAULT */
> + bx lr
> +
>
> .Lmisaligned8:
> ldrd data1a, data1b, [src]
> @@ -177,4 +219,6 @@ def_fn strlen p2align=6
> movne data1a, const_m1
> mov const_0, #0
> b .Lstart_realigned
> + .cfi_endproc
> + .fnend
> .size strlen, . - strlen
> diff --git a/newlib/libc/machine/arm/strlen-stub.c b/newlib/libc/machine/arm/strlen-stub.c
> index fc2daf16f..4a0bb8cbb 100644
> --- a/newlib/libc/machine/arm/strlen-stub.c
> +++ b/newlib/libc/machine/arm/strlen-stub.c
> @@ -58,6 +58,11 @@ strlen (const char* str)
> "data .req r3\n\t"
> "addr .req r1\n\t"
>
> +#ifdef __ARM_FEATURE_PAC_DEFAULT
> + "pac ip, lr, sp\n\t"
> + "str ip, [sp, #-4]!\n\t"
> +#endif
> +
> #ifdef _ISA_ARM_7
> "pld [r0]\n\t"
> #endif
> @@ -167,6 +172,10 @@ strlen (const char* str)
> "it ne\n\t"
> "addne len, len, #1\n\t"
> # endif
> +#endif
> +#ifdef __ARM_FEATURE_PAC_DEFAULT
> + "ldr ip, [sp], #4\n\t"
> + "aut ip, lr, sp\n\t"
> #endif
> "bx lr\n\t");
> }
> diff --git a/newlib/libc/machine/arm/strlen-thumb2-Os.S b/newlib/libc/machine/arm/strlen-thumb2-Os.S
> index 961f41a0a..823b0310e 100644
> --- a/newlib/libc/machine/arm/strlen-thumb2-Os.S
> +++ b/newlib/libc/machine/arm/strlen-thumb2-Os.S
> @@ -25,6 +25,7 @@
> OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
>
> #include "acle-compat.h"
> +#include "pacbti.h"
>
> .macro def_fn f p2align=0
> .text
> @@ -33,8 +34,9 @@
> .type \f, %function
> \f:
> .endm
> -
> -#if __ARM_ARCH_ISA_THUMB >= 2 && __ARM_ARCH >= 7
> +#if __ARM_ARCH_8M_MAIN__
> + /* keep config inherited from -march= */
> +#elif __ARM_ARCH_ISA_THUMB >= 2 && __ARM_ARCH >= 7
> .arch armv7
> #else
> .arch armv6t2
> @@ -44,11 +46,16 @@
> .syntax unified
>
> def_fn strlen p2align=1
> + .fnstart
> + .cfi_startproc
> + pacbti_prologue
> mov r3, r0
> 1: ldrb.w r2, [r3], #1
> cmp r2, #0
> bne 1b
> subs r0, r3, r0
> subs r0, #1
> - bx lr
> + pacbti_epilogue
> + .cfi_endproc
> + .fnend
> .size strlen, . - strlen
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 3/8] newlib: libc: strlen M-profile PACBTI-enablement
2022-07-05 15:39 ` Richard Earnshaw
@ 2022-07-05 16:30 ` Victor L. Do Nascimento
2022-07-06 9:07 ` Richard Earnshaw
0 siblings, 1 reply; 12+ messages in thread
From: Victor L. Do Nascimento @ 2022-07-05 16:30 UTC (permalink / raw)
To: Richard Earnshaw; +Cc: newlib
Richard Earnshaw <Richard.Earnshaw@foss.arm.com> writes:
> On 05/07/2022 14:58, Victor Do Nascimento wrote:
>> Add function prologue/epilogue to conditionally add BTI landing pads
>> and/or PAC code generation & authentication instructions depending on
>> compilation flags.
>> This patch enables PACBTI for all relevant variants of strlen:
>> * Newlib for armv8.1-m.main+pacbti
>> * Newlib for armv8.1-m.main+pacbti+mve
>> * Newlib-nano
>> ---
>> newlib/libc/machine/arm/strlen-armv7.S | 52 ++++++++++++++++++++--
>> newlib/libc/machine/arm/strlen-stub.c | 9 ++++
>> newlib/libc/machine/arm/strlen-thumb2-Os.S | 13 ++++--
>> 3 files changed, 67 insertions(+), 7 deletions(-)
>> diff --git a/newlib/libc/machine/arm/strlen-armv7.S
>> b/newlib/libc/machine/arm/strlen-armv7.S
>> index f3dda0d60..18c8226d0 100644
>> --- a/newlib/libc/machine/arm/strlen-armv7.S
>> +++ b/newlib/libc/machine/arm/strlen-armv7.S
>> @@ -59,6 +59,7 @@
>> OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
>> #include "acle-compat.h"
>> +#include "pacbti.h"
>> .macro def_fn f p2align=0
>> .text
>> @@ -77,7 +78,9 @@
>> #endif
>> /* This code requires Thumb. */
>> -#if __ARM_ARCH_PROFILE == 'M'
>> +#if __ARM_ARCH_8M_MAIN__
>
> These GCC architecture macros (those that end with '__') aren't portable and are
> essentially deprecated. What exactly are you trying to achieve here?
It was my attempt at circumventing the .arch directives below.
As these older architecture lack the support for PACBTI instructions, if
we don't prevent the selection of the wrong target architecture, when
said instructions are encountered they cause Newlib compilation to fail.
In particular, I needed to distinguish between armv7e-m and
armv8.1-m.main and chose the __ARM_ARCH_8M_MAIN__ macro out of the
output from using the -dM GCC preprocessor flag.
Will fix.
>> + /* keep config inherited from -march= */
>> +#elif __ARM_ARCH_PROFILE == 'M'
>> .arch armv7e-m
>> #else
>> .arch armv6t2
>> @@ -100,8 +103,34 @@
>> #define tmp2 r5
>> def_fn strlen p2align=6
>> + .fnstart
>> + .cfi_startproc
>> + /* common pacbti_prologue macro from pacbti.h not used.
>> + handwritten prologue saves one push instruction. */
>> +#if __ARM_FEATURE_PAC_DEFAULT
>> +#if __ARM_FEATURE_BTI_DEFAULT
>> + pacbti ip, lr, sp
>> +#else
>> + pac ip, lr, sp
>> +#endif /* __ARM_FEATURE_BTI_DEFAULT */
>> + push {r4, r5, ip}
>> + .save {r4, r5, ra_auth_code}
>> + .cfi_def_cfa_offset 12
>> + .cfi_offset 143, -4
>> + .cfi_offset 5, -8
>> + .cfi_offset 4, -12
>> +
>> +#else
>> +#if __ARM_FEATURE_BTI_DEFAULT
>> + bti
>> +#endif /* __ARM_FEATURE_BTI_DEFAULT */
>> + push {r4, r5}
>> + .save {r4, r5}
>> + .cfi_def_cfa_offset 8
>> + .cfi_offset 5, -4
>> + .cfi_offset 4, -8
>> +#endif /* __ARM_FEATURE_PAC_DEFAULT */
>> pld [srcin, #0]
>> - strd r4, r5, [sp, #-8]!
>> bic src, srcin, #7
>> mvn const_m1, #0
>> ands tmp1, srcin, #7 /* (8 - bytes) to alignment. */
>> @@ -159,9 +188,22 @@ def_fn strlen p2align=6
>> rev data1a, data1a
>> #endif
>> clz data1a, data1a
>> - ldrd r4, r5, [sp], #8
>> add result, result, data1a, lsr #3 /* Bits -> Bytes. */
>> - bx lr
>> +#if __ARM_FEATURE_PAC_DEFAULT
>> + pop {r4, r5, ip}
>> + .cfi_restore 4
>> + .cfi_restore 5
>> + .cfi_restore 143
>> + .cfi_def_cfa_offset 0
>> + aut ip, lr, sp
>> +#else
>> + ldrd r4, r5, [sp], #8
>> + .cfi_restore 4
>> + .cfi_restore 5
>> + .cfi_def_cfa_offset 0
>> +#endif /* __ARM_FEATURE_PAC_DEFAULT */
>> + bx lr
>> +
>> .Lmisaligned8:
>> ldrd data1a, data1b, [src]
>> @@ -177,4 +219,6 @@ def_fn strlen p2align=6
>> movne data1a, const_m1
>> mov const_0, #0
>> b .Lstart_realigned
>> + .cfi_endproc
>> + .fnend
>> .size strlen, . - strlen
>> diff --git a/newlib/libc/machine/arm/strlen-stub.c b/newlib/libc/machine/arm/strlen-stub.c
>> index fc2daf16f..4a0bb8cbb 100644
>> --- a/newlib/libc/machine/arm/strlen-stub.c
>> +++ b/newlib/libc/machine/arm/strlen-stub.c
>> @@ -58,6 +58,11 @@ strlen (const char* str)
>> "data .req r3\n\t"
>> "addr .req r1\n\t"
>> +#ifdef __ARM_FEATURE_PAC_DEFAULT
>> + "pac ip, lr, sp\n\t"
>> + "str ip, [sp, #-4]!\n\t"
>> +#endif
>> +
>> #ifdef _ISA_ARM_7
>> "pld [r0]\n\t"
>> #endif
>> @@ -167,6 +172,10 @@ strlen (const char* str)
>> "it ne\n\t"
>> "addne len, len, #1\n\t"
>> # endif
>> +#endif
>> +#ifdef __ARM_FEATURE_PAC_DEFAULT
>> + "ldr ip, [sp], #4\n\t"
>> + "aut ip, lr, sp\n\t"
>> #endif
>> "bx lr\n\t");
>> }
>> diff --git a/newlib/libc/machine/arm/strlen-thumb2-Os.S b/newlib/libc/machine/arm/strlen-thumb2-Os.S
>> index 961f41a0a..823b0310e 100644
>> --- a/newlib/libc/machine/arm/strlen-thumb2-Os.S
>> +++ b/newlib/libc/machine/arm/strlen-thumb2-Os.S
>> @@ -25,6 +25,7 @@
>> OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
>> #include "acle-compat.h"
>> +#include "pacbti.h"
>> .macro def_fn f p2align=0
>> .text
>> @@ -33,8 +34,9 @@
>> .type \f, %function
>> \f:
>> .endm
>> -
>> -#if __ARM_ARCH_ISA_THUMB >= 2 && __ARM_ARCH >= 7
>> +#if __ARM_ARCH_8M_MAIN__
>> + /* keep config inherited from -march= */
>> +#elif __ARM_ARCH_ISA_THUMB >= 2 && __ARM_ARCH >= 7
>> .arch armv7
>> #else
>> .arch armv6t2
>> @@ -44,11 +46,16 @@
>> .syntax unified
>> def_fn strlen p2align=1
>> + .fnstart
>> + .cfi_startproc
>> + pacbti_prologue
>> mov r3, r0
>> 1: ldrb.w r2, [r3], #1
>> cmp r2, #0
>> bne 1b
>> subs r0, r3, r0
>> subs r0, #1
>> - bx lr
>> + pacbti_epilogue
>> + .cfi_endproc
>> + .fnend
>> .size strlen, . - strlen
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: [PATCH 3/8] newlib: libc: strlen M-profile PACBTI-enablement
2022-07-05 16:30 ` Victor L. Do Nascimento
@ 2022-07-06 9:07 ` Richard Earnshaw
0 siblings, 0 replies; 12+ messages in thread
From: Richard Earnshaw @ 2022-07-06 9:07 UTC (permalink / raw)
To: Victor L. Do Nascimento; +Cc: newlib
On 05/07/2022 17:30, Victor L. Do Nascimento wrote:
> Richard Earnshaw <Richard.Earnshaw@foss.arm.com> writes:
>
>> On 05/07/2022 14:58, Victor Do Nascimento wrote:
>>> Add function prologue/epilogue to conditionally add BTI landing pads
>>> and/or PAC code generation & authentication instructions depending on
>>> compilation flags.
>>> This patch enables PACBTI for all relevant variants of strlen:
>>> * Newlib for armv8.1-m.main+pacbti
>>> * Newlib for armv8.1-m.main+pacbti+mve
>>> * Newlib-nano
>>> ---
>>> newlib/libc/machine/arm/strlen-armv7.S | 52 ++++++++++++++++++++--
>>> newlib/libc/machine/arm/strlen-stub.c | 9 ++++
>>> newlib/libc/machine/arm/strlen-thumb2-Os.S | 13 ++++--
>>> 3 files changed, 67 insertions(+), 7 deletions(-)
>>> diff --git a/newlib/libc/machine/arm/strlen-armv7.S
>>> b/newlib/libc/machine/arm/strlen-armv7.S
>>> index f3dda0d60..18c8226d0 100644
>>> --- a/newlib/libc/machine/arm/strlen-armv7.S
>>> +++ b/newlib/libc/machine/arm/strlen-armv7.S
>>> @@ -59,6 +59,7 @@
>>> OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
>>> #include "acle-compat.h"
>>> +#include "pacbti.h"
>>> .macro def_fn f p2align=0
>>> .text
>>> @@ -77,7 +78,9 @@
>>> #endif
>>> /* This code requires Thumb. */
>>> -#if __ARM_ARCH_PROFILE == 'M'
>>> +#if __ARM_ARCH_8M_MAIN__
>>
>> These GCC architecture macros (those that end with '__') aren't portable and are
>> essentially deprecated. What exactly are you trying to achieve here?
>
> It was my attempt at circumventing the .arch directives below.
> As these older architecture lack the support for PACBTI instructions, if
> we don't prevent the selection of the wrong target architecture, when
> said instructions are encountered they cause Newlib compilation to fail.
>
> In particular, I needed to distinguish between armv7e-m and
> armv8.1-m.main and chose the __ARM_ARCH_8M_MAIN__ macro out of the
> output from using the -dM GCC preprocessor flag.
>
> Will fix.
I'd suggest you use __ARM_ARCH >= 8, which should be enough
(technically, of course, it should be >= 800, but GCC is broken on this).
R.
>
>>> + /* keep config inherited from -march= */
>>> +#elif __ARM_ARCH_PROFILE == 'M'
>>> .arch armv7e-m
>>> #else
>>> .arch armv6t2
>>> @@ -100,8 +103,34 @@
>>> #define tmp2 r5
>>> def_fn strlen p2align=6
>>> + .fnstart
>>> + .cfi_startproc
>>> + /* common pacbti_prologue macro from pacbti.h not used.
>>> + handwritten prologue saves one push instruction. */
>>> +#if __ARM_FEATURE_PAC_DEFAULT
>>> +#if __ARM_FEATURE_BTI_DEFAULT
>>> + pacbti ip, lr, sp
>>> +#else
>>> + pac ip, lr, sp
>>> +#endif /* __ARM_FEATURE_BTI_DEFAULT */
>>> + push {r4, r5, ip}
>>> + .save {r4, r5, ra_auth_code}
>>> + .cfi_def_cfa_offset 12
>>> + .cfi_offset 143, -4
>>> + .cfi_offset 5, -8
>>> + .cfi_offset 4, -12
>>> +
>>> +#else
>>> +#if __ARM_FEATURE_BTI_DEFAULT
>>> + bti
>>> +#endif /* __ARM_FEATURE_BTI_DEFAULT */
>>> + push {r4, r5}
>>> + .save {r4, r5}
>>> + .cfi_def_cfa_offset 8
>>> + .cfi_offset 5, -4
>>> + .cfi_offset 4, -8
>>> +#endif /* __ARM_FEATURE_PAC_DEFAULT */
>>> pld [srcin, #0]
>>> - strd r4, r5, [sp, #-8]!
>>> bic src, srcin, #7
>>> mvn const_m1, #0
>>> ands tmp1, srcin, #7 /* (8 - bytes) to alignment. */
>>> @@ -159,9 +188,22 @@ def_fn strlen p2align=6
>>> rev data1a, data1a
>>> #endif
>>> clz data1a, data1a
>>> - ldrd r4, r5, [sp], #8
>>> add result, result, data1a, lsr #3 /* Bits -> Bytes. */
>>> - bx lr
>>> +#if __ARM_FEATURE_PAC_DEFAULT
>>> + pop {r4, r5, ip}
>>> + .cfi_restore 4
>>> + .cfi_restore 5
>>> + .cfi_restore 143
>>> + .cfi_def_cfa_offset 0
>>> + aut ip, lr, sp
>>> +#else
>>> + ldrd r4, r5, [sp], #8
>>> + .cfi_restore 4
>>> + .cfi_restore 5
>>> + .cfi_def_cfa_offset 0
>>> +#endif /* __ARM_FEATURE_PAC_DEFAULT */
>>> + bx lr
>>> +
>>> .Lmisaligned8:
>>> ldrd data1a, data1b, [src]
>>> @@ -177,4 +219,6 @@ def_fn strlen p2align=6
>>> movne data1a, const_m1
>>> mov const_0, #0
>>> b .Lstart_realigned
>>> + .cfi_endproc
>>> + .fnend
>>> .size strlen, . - strlen
>>> diff --git a/newlib/libc/machine/arm/strlen-stub.c b/newlib/libc/machine/arm/strlen-stub.c
>>> index fc2daf16f..4a0bb8cbb 100644
>>> --- a/newlib/libc/machine/arm/strlen-stub.c
>>> +++ b/newlib/libc/machine/arm/strlen-stub.c
>>> @@ -58,6 +58,11 @@ strlen (const char* str)
>>> "data .req r3\n\t"
>>> "addr .req r1\n\t"
>>> +#ifdef __ARM_FEATURE_PAC_DEFAULT
>>> + "pac ip, lr, sp\n\t"
>>> + "str ip, [sp, #-4]!\n\t"
>>> +#endif
>>> +
>>> #ifdef _ISA_ARM_7
>>> "pld [r0]\n\t"
>>> #endif
>>> @@ -167,6 +172,10 @@ strlen (const char* str)
>>> "it ne\n\t"
>>> "addne len, len, #1\n\t"
>>> # endif
>>> +#endif
>>> +#ifdef __ARM_FEATURE_PAC_DEFAULT
>>> + "ldr ip, [sp], #4\n\t"
>>> + "aut ip, lr, sp\n\t"
>>> #endif
>>> "bx lr\n\t");
>>> }
>>> diff --git a/newlib/libc/machine/arm/strlen-thumb2-Os.S b/newlib/libc/machine/arm/strlen-thumb2-Os.S
>>> index 961f41a0a..823b0310e 100644
>>> --- a/newlib/libc/machine/arm/strlen-thumb2-Os.S
>>> +++ b/newlib/libc/machine/arm/strlen-thumb2-Os.S
>>> @@ -25,6 +25,7 @@
>>> OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
>>> #include "acle-compat.h"
>>> +#include "pacbti.h"
>>> .macro def_fn f p2align=0
>>> .text
>>> @@ -33,8 +34,9 @@
>>> .type \f, %function
>>> \f:
>>> .endm
>>> -
>>> -#if __ARM_ARCH_ISA_THUMB >= 2 && __ARM_ARCH >= 7
>>> +#if __ARM_ARCH_8M_MAIN__
>>> + /* keep config inherited from -march= */
>>> +#elif __ARM_ARCH_ISA_THUMB >= 2 && __ARM_ARCH >= 7
>>> .arch armv7
>>> #else
>>> .arch armv6t2
>>> @@ -44,11 +46,16 @@
>>> .syntax unified
>>> def_fn strlen p2align=1
>>> + .fnstart
>>> + .cfi_startproc
>>> + pacbti_prologue
>>> mov r3, r0
>>> 1: ldrb.w r2, [r3], #1
>>> cmp r2, #0
>>> bne 1b
>>> subs r0, r3, r0
>>> subs r0, #1
>>> - bx lr
>>> + pacbti_epilogue
>>> + .cfi_endproc
>>> + .fnend
>>> .size strlen, . - strlen
^ permalink raw reply [flat|nested] 12+ messages in thread
end of thread, other threads:[~2022-07-06 9:07 UTC | newest]
Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-07-05 13:58 [PATCH 0/8] Implement assembly cortex-M PACBTI functionality Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 1/8] newlib: libc: define M-profile PACBTI-enablement macros Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 2/8] newlib: libc: strcmp M-profile PACBTI-enablement Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 3/8] newlib: libc: strlen " Victor Do Nascimento
2022-07-05 15:39 ` Richard Earnshaw
2022-07-05 16:30 ` Victor L. Do Nascimento
2022-07-06 9:07 ` Richard Earnshaw
2022-07-05 13:58 ` [PATCH 4/8] newlib: libc: memchr " Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 5/8] newlib: libc: memcpy " Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 6/8] newlib: libc: setjmp/longjmp " Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 7/8] newlib: libc: aeabi_memmove " Victor Do Nascimento
2022-07-05 13:58 ` [PATCH 8/8] newlib: libc: aeabi_memset " Victor Do Nascimento
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