[Qemu-devel] [PATCH v2 08/16] tests/tcg/arm: add ARMv6-M UNDEFINED 32-bit instruction test

Alex Bennée posted 16 patches 6 years, 7 months ago
Maintainers: Aurelien Jarno <aurelien@aurel32.net>, Aleksandar Markovic <amarkovic@wavecomp.com>, Aleksandar Rikalo <arikalo@wavecomp.com>
[Qemu-devel] [PATCH v2 08/16] tests/tcg/arm: add ARMv6-M UNDEFINED 32-bit instruction test
Posted by Alex Bennée 6 years, 7 months ago
From: Stefan Hajnoczi <stefanha@redhat.com>

Test that 32-bit instructions declared UNDEFINED in the ARMv6-M
Reference Manual really do raise an exception.  Also test that the 6
32-bit instructions defined in the ARMv6-M Reference Manual do not raise
an exception.

Based-on: <20181029194519.15628-1-stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20181129185113.30353-1-stefanha@redhat.com>
[AJB: integrated into system tests]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

---
v2
  - added to series
  - used softmmu-target Makefile with single compile/link step
  - launches with -kernel
  - drop .hex file
---
 tests/tcg/arm/Makefile.softmmu-target |  29 +++++
 tests/tcg/arm/test-armv6m-undef.S     | 154 ++++++++++++++++++++++++++
 tests/tcg/arm/test-armv6m-undef.ld    |  21 ++++
 3 files changed, 204 insertions(+)
 create mode 100644 tests/tcg/arm/Makefile.softmmu-target
 create mode 100644 tests/tcg/arm/test-armv6m-undef.S
 create mode 100644 tests/tcg/arm/test-armv6m-undef.ld

diff --git a/tests/tcg/arm/Makefile.softmmu-target b/tests/tcg/arm/Makefile.softmmu-target
new file mode 100644
index 0000000000..49d48d8a1c
--- /dev/null
+++ b/tests/tcg/arm/Makefile.softmmu-target
@@ -0,0 +1,29 @@
+# -*- Mode: makefile -*-
+#
+# ARM SoftMMU tests - included from tests/tcg/Makefile
+#
+
+ifeq ($(TARGET_ABI_DIR),arm)
+
+ARM_SRC=$(SRC_PATH)/tests/tcg/arm
+
+# Set search path for all sources
+VPATH 		+= $(ARM_SRC)
+
+ARM_TESTS=test-armv6m-undef
+
+TESTS += $(ARM_TESTS)
+
+CFLAGS+=-Wl,--build-id=none -x assembler-with-cpp
+LDFLAGS+=-nostdlib -N -static
+
+%: %.S %.ld
+	$(CC) $(CFLAGS) $(ASFLAGS) $< -o $@ $(LDFLAGS) -T $(ARM_SRC)/$@.ld
+
+# Specific Test Rules
+
+test-armv6m-undef: EXTRA_CFLAGS+=-mcpu=cortex-m0
+
+run-test-armv6m-undef: QEMU_OPTS+=-semihosting -M microbit -kernel
+
+endif
diff --git a/tests/tcg/arm/test-armv6m-undef.S b/tests/tcg/arm/test-armv6m-undef.S
new file mode 100644
index 0000000000..d18ca56b4a
--- /dev/null
+++ b/tests/tcg/arm/test-armv6m-undef.S
@@ -0,0 +1,154 @@
+/*
+ * Test ARMv6-M UNDEFINED 32-bit instructions
+ *
+ * Copyright 2018 Red Hat Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2
+ * or later. See the COPYING file in the top-level directory.
+ */
+
+/*
+ * Test that UNDEFINED 32-bit instructions fault as expected.  This is an
+ * interesting test because ARMv6-M shares code with its more fully-featured
+ * siblings and it's necessary to verify that its limited instruction set is
+ * emulated correctly.
+ *
+ * The emulator must be invoked with -semihosting so that the test case can
+ * terminate with exit code 0 on success or 1 on failure.
+ *
+ * Failures can be debugged with -d in_asm,int,exec,cpu and the
+ * gdbstub (-S -s).
+ */
+
+.syntax unified
+.cpu cortex-m0
+.thumb
+
+/*
+ * Memory map
+ */
+#define SRAM_BASE 0x20000000
+#define SRAM_SIZE (16 * 1024)
+
+/*
+ * Semihosting interface on ARM T32
+ * See "Semihosting for AArch32 and AArch64 Version 2.0 Documentation" by ARM
+ */
+#define semihosting_call bkpt 0xab
+#define SYS_EXIT 0x18
+
+vector_table:
+    .word SRAM_BASE + SRAM_SIZE /* 0. SP_main */
+    .word exc_reset_thumb       /* 1. Reset */
+    .word 0                     /* 2. NMI */
+    .word exc_hard_fault_thumb  /* 3. HardFault */
+    .rept 7
+    .word 0                     /* 4-10. Reserved */
+    .endr
+    .word 0                     /* 11. SVCall */
+    .word 0                     /* 12. Reserved */
+    .word 0                     /* 13. Reserved */
+    .word 0                     /* 14. PendSV */
+    .word 0                     /* 15. SysTick */
+    .rept 32
+    .word 0                     /* 16-47. External Interrupts */
+    .endr
+
+exc_reset:
+.equ exc_reset_thumb, exc_reset + 1
+.global exc_reset_thumb
+    /* The following 32-bit UNDEFINED instructions are tested by executing
+     * them.  The HardFault exception handler should execute and return to
+     * the next test case.  If no exception is raised the test fails.
+     */
+
+    /* Table A5-9 32-bit Thumb encoding */
+    .short 0b1110100000000000
+    .short 0b0000000000000000
+    b not_reached
+    .short 0b1110100000000000
+    .short 0b1000000000000000
+    b not_reached
+    .short 0b1111100000000000
+    .short 0b0000000000000000
+    b not_reached
+    .short 0b1111100000000000
+    .short 0b1000000000000000
+    b not_reached
+    .short 0b1111000000000000
+    .short 0b0000000000000000
+    b not_reached
+
+    /* Table A5-10 Branch and miscellaneous control instructions */
+    .short 0b1111011111110000
+    .short 0b1010000000000000
+    b not_reached
+
+    /* The following are valid 32-bit instructions that must not raise a
+     * HardFault.
+     */
+
+    /* B4.2.3 Move to Special Register (moves to IPSR are ignored) */
+    msr ipsr, r0
+    b 1f
+    b not_reached
+1:
+    /* B4.2.2 Move from Special Register */
+    mrs r0, ipsr
+    b 1f
+    b not_reached
+1:
+    /* A6.7.13 Branch with Link (immediate) */
+    bl 1f
+1:
+    b 1f
+    b not_reached
+1:
+    /* A6.7.21 Data Memory Barrier */
+    dmb
+    b 1f
+    b not_reached
+1:
+    /* A6.7.22 Data Synchronization Barrier */
+    dsb
+    b 1f
+    b not_reached
+1:
+    /* A6.7.24 Instruction Memory Barrier */
+    isb
+    b 1f
+    b not_reached
+1:
+
+    /* Success! */
+    movs r0, 1
+    b exit
+
+not_reached: /* Failure :( */
+    movs r0, 0
+    b exit
+
+/* When a HardFault occurs, return to pc+6 (test cases are 3 halfwords long) */
+exc_hard_fault:
+.equ exc_hard_fault_thumb, exc_hard_fault + 1
+.global exc_hard_fault_thumb
+    ldr r0, [sp, 0x18]
+    adds r0, 6
+    str r0, [sp, 0x18]
+    bx lr
+
+/*
+ * exit: Terminate emulator
+ * @r0: 0 - failure, 1 - success
+ */
+exit:
+    movs r1, 0
+    cmp r0, 1
+    bne 1f
+    ldr r1, ADP_Stopped_ApplicationExit
+1:
+    movs r0, SYS_EXIT
+    semihosting_call
+.align 2
+ADP_Stopped_ApplicationExit:
+    .word 0x20026
diff --git a/tests/tcg/arm/test-armv6m-undef.ld b/tests/tcg/arm/test-armv6m-undef.ld
new file mode 100644
index 0000000000..43dbbf17d5
--- /dev/null
+++ b/tests/tcg/arm/test-armv6m-undef.ld
@@ -0,0 +1,21 @@
+ENTRY(exc_reset_thumb)
+
+SECTIONS
+{
+    . = 0x0;
+    .text : {
+        *(.text)
+    }
+    .data : {
+        *(.data)
+    }
+    .rodata : {
+        *(.rodata)
+    }
+    .bss : {
+        *(.bss)
+    }
+    /DISCARD/ : {
+        *(.ARM.attributes)
+    }
+}
-- 
2.20.1


Re: [Qemu-devel] [PATCH v2 08/16] tests/tcg/arm: add ARMv6-M UNDEFINED 32-bit instruction test
Posted by Philippe Mathieu-Daudé 6 years, 7 months ago
On 2/28/19 9:25 PM, Alex Bennée wrote:
> From: Stefan Hajnoczi <stefanha@redhat.com>
> 
> Test that 32-bit instructions declared UNDEFINED in the ARMv6-M
> Reference Manual really do raise an exception.  Also test that the 6
> 32-bit instructions defined in the ARMv6-M Reference Manual do not raise
> an exception.
> 
> Based-on: <20181029194519.15628-1-stefanha@redhat.com>

^ cut 'Based-on' from git history?

> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> Message-Id: <20181129185113.30353-1-stefanha@redhat.com>
> [AJB: integrated into system tests]
> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
> 
> ---
> v2
>   - added to series
>   - used softmmu-target Makefile with single compile/link step
>   - launches with -kernel
>   - drop .hex file
> ---
>  tests/tcg/arm/Makefile.softmmu-target |  29 +++++
>  tests/tcg/arm/test-armv6m-undef.S     | 154 ++++++++++++++++++++++++++
>  tests/tcg/arm/test-armv6m-undef.ld    |  21 ++++
>  3 files changed, 204 insertions(+)
>  create mode 100644 tests/tcg/arm/Makefile.softmmu-target
>  create mode 100644 tests/tcg/arm/test-armv6m-undef.S
>  create mode 100644 tests/tcg/arm/test-armv6m-undef.ld
> 
> diff --git a/tests/tcg/arm/Makefile.softmmu-target b/tests/tcg/arm/Makefile.softmmu-target
> new file mode 100644
> index 0000000000..49d48d8a1c
> --- /dev/null
> +++ b/tests/tcg/arm/Makefile.softmmu-target
> @@ -0,0 +1,29 @@
> +# -*- Mode: makefile -*-
> +#
> +# ARM SoftMMU tests - included from tests/tcg/Makefile
> +#
> +
> +ifeq ($(TARGET_ABI_DIR),arm)
> +
> +ARM_SRC=$(SRC_PATH)/tests/tcg/arm
> +
> +# Set search path for all sources
> +VPATH 		+= $(ARM_SRC)
> +
> +ARM_TESTS=test-armv6m-undef
> +
> +TESTS += $(ARM_TESTS)
> +
> +CFLAGS+=-Wl,--build-id=none -x assembler-with-cpp
> +LDFLAGS+=-nostdlib -N -static
> +
> +%: %.S %.ld
> +	$(CC) $(CFLAGS) $(ASFLAGS) $< -o $@ $(LDFLAGS) -T $(ARM_SRC)/$@.ld
> +
> +# Specific Test Rules
> +
> +test-armv6m-undef: EXTRA_CFLAGS+=-mcpu=cortex-m0
> +
> +run-test-armv6m-undef: QEMU_OPTS+=-semihosting -M microbit -kernel
> +
> +endif
> diff --git a/tests/tcg/arm/test-armv6m-undef.S b/tests/tcg/arm/test-armv6m-undef.S
> new file mode 100644
> index 0000000000..d18ca56b4a
> --- /dev/null
> +++ b/tests/tcg/arm/test-armv6m-undef.S
> @@ -0,0 +1,154 @@
> +/*
> + * Test ARMv6-M UNDEFINED 32-bit instructions
> + *
> + * Copyright 2018 Red Hat Inc.
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2
> + * or later. See the COPYING file in the top-level directory.
> + */
> +
> +/*
> + * Test that UNDEFINED 32-bit instructions fault as expected.  This is an
> + * interesting test because ARMv6-M shares code with its more fully-featured
> + * siblings and it's necessary to verify that its limited instruction set is
> + * emulated correctly.
> + *
> + * The emulator must be invoked with -semihosting so that the test case can
> + * terminate with exit code 0 on success or 1 on failure.
> + *
> + * Failures can be debugged with -d in_asm,int,exec,cpu and the
> + * gdbstub (-S -s).
> + */
> +
> +.syntax unified
> +.cpu cortex-m0
> +.thumb
> +
> +/*
> + * Memory map
> + */
> +#define SRAM_BASE 0x20000000
> +#define SRAM_SIZE (16 * 1024)
> +
> +/*
> + * Semihosting interface on ARM T32
> + * See "Semihosting for AArch32 and AArch64 Version 2.0 Documentation" by ARM
> + */
> +#define semihosting_call bkpt 0xab
> +#define SYS_EXIT 0x18
> +
> +vector_table:
> +    .word SRAM_BASE + SRAM_SIZE /* 0. SP_main */
> +    .word exc_reset_thumb       /* 1. Reset */
> +    .word 0                     /* 2. NMI */
> +    .word exc_hard_fault_thumb  /* 3. HardFault */
> +    .rept 7
> +    .word 0                     /* 4-10. Reserved */
> +    .endr
> +    .word 0                     /* 11. SVCall */
> +    .word 0                     /* 12. Reserved */
> +    .word 0                     /* 13. Reserved */
> +    .word 0                     /* 14. PendSV */
> +    .word 0                     /* 15. SysTick */
> +    .rept 32
> +    .word 0                     /* 16-47. External Interrupts */
> +    .endr
> +
> +exc_reset:
> +.equ exc_reset_thumb, exc_reset + 1
> +.global exc_reset_thumb
> +    /* The following 32-bit UNDEFINED instructions are tested by executing
> +     * them.  The HardFault exception handler should execute and return to
> +     * the next test case.  If no exception is raised the test fails.
> +     */
> +
> +    /* Table A5-9 32-bit Thumb encoding */
> +    .short 0b1110100000000000
> +    .short 0b0000000000000000
> +    b not_reached
> +    .short 0b1110100000000000
> +    .short 0b1000000000000000
> +    b not_reached
> +    .short 0b1111100000000000
> +    .short 0b0000000000000000
> +    b not_reached
> +    .short 0b1111100000000000
> +    .short 0b1000000000000000
> +    b not_reached
> +    .short 0b1111000000000000
> +    .short 0b0000000000000000
> +    b not_reached
> +
> +    /* Table A5-10 Branch and miscellaneous control instructions */
> +    .short 0b1111011111110000
> +    .short 0b1010000000000000
> +    b not_reached
> +
> +    /* The following are valid 32-bit instructions that must not raise a
> +     * HardFault.
> +     */
> +
> +    /* B4.2.3 Move to Special Register (moves to IPSR are ignored) */
> +    msr ipsr, r0
> +    b 1f
> +    b not_reached
> +1:
> +    /* B4.2.2 Move from Special Register */
> +    mrs r0, ipsr
> +    b 1f
> +    b not_reached
> +1:
> +    /* A6.7.13 Branch with Link (immediate) */
> +    bl 1f
> +1:
> +    b 1f
> +    b not_reached
> +1:
> +    /* A6.7.21 Data Memory Barrier */
> +    dmb
> +    b 1f
> +    b not_reached
> +1:
> +    /* A6.7.22 Data Synchronization Barrier */
> +    dsb
> +    b 1f
> +    b not_reached
> +1:
> +    /* A6.7.24 Instruction Memory Barrier */
> +    isb
> +    b 1f
> +    b not_reached
> +1:
> +
> +    /* Success! */
> +    movs r0, 1
> +    b exit
> +
> +not_reached: /* Failure :( */
> +    movs r0, 0
> +    b exit
> +
> +/* When a HardFault occurs, return to pc+6 (test cases are 3 halfwords long) */
> +exc_hard_fault:
> +.equ exc_hard_fault_thumb, exc_hard_fault + 1
> +.global exc_hard_fault_thumb
> +    ldr r0, [sp, 0x18]
> +    adds r0, 6
> +    str r0, [sp, 0x18]
> +    bx lr
> +
> +/*
> + * exit: Terminate emulator
> + * @r0: 0 - failure, 1 - success
> + */
> +exit:
> +    movs r1, 0
> +    cmp r0, 1
> +    bne 1f
> +    ldr r1, ADP_Stopped_ApplicationExit
> +1:
> +    movs r0, SYS_EXIT
> +    semihosting_call
> +.align 2
> +ADP_Stopped_ApplicationExit:
> +    .word 0x20026
> diff --git a/tests/tcg/arm/test-armv6m-undef.ld b/tests/tcg/arm/test-armv6m-undef.ld
> new file mode 100644
> index 0000000000..43dbbf17d5
> --- /dev/null
> +++ b/tests/tcg/arm/test-armv6m-undef.ld
> @@ -0,0 +1,21 @@
> +ENTRY(exc_reset_thumb)
> +
> +SECTIONS
> +{
> +    . = 0x0;
> +    .text : {
> +        *(.text)
> +    }
> +    .data : {
> +        *(.data)
> +    }
> +    .rodata : {
> +        *(.rodata)
> +    }
> +    .bss : {
> +        *(.bss)
> +    }
> +    /DISCARD/ : {
> +        *(.ARM.attributes)
> +    }
> +}
> 

Re: [Qemu-devel] [PATCH v2 08/16] tests/tcg/arm: add ARMv6-M UNDEFINED 32-bit instruction test
Posted by Alex Bennée 6 years, 7 months ago
Philippe Mathieu-Daudé <philmd@redhat.com> writes:

> On 2/28/19 9:25 PM, Alex Bennée wrote:
>> From: Stefan Hajnoczi <stefanha@redhat.com>
>>
>> Test that 32-bit instructions declared UNDEFINED in the ARMv6-M
>> Reference Manual really do raise an exception.  Also test that the 6
>> 32-bit instructions defined in the ARMv6-M Reference Manual do not raise
>> an exception.
>>
>> Based-on: <20181029194519.15628-1-stefanha@redhat.com>
>
> ^ cut 'Based-on' from git history?

Yeah - we really only need the Message ID.

>
>> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
>> Message-Id: <20181129185113.30353-1-stefanha@redhat.com>
>> [AJB: integrated into system tests]
>> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
>>
>> ---
>> v2
>>   - added to series
>>   - used softmmu-target Makefile with single compile/link step
>>   - launches with -kernel
>>   - drop .hex file
>> ---
>>  tests/tcg/arm/Makefile.softmmu-target |  29 +++++
>>  tests/tcg/arm/test-armv6m-undef.S     | 154 ++++++++++++++++++++++++++
>>  tests/tcg/arm/test-armv6m-undef.ld    |  21 ++++
>>  3 files changed, 204 insertions(+)
>>  create mode 100644 tests/tcg/arm/Makefile.softmmu-target
>>  create mode 100644 tests/tcg/arm/test-armv6m-undef.S
>>  create mode 100644 tests/tcg/arm/test-armv6m-undef.ld
>>
>> diff --git a/tests/tcg/arm/Makefile.softmmu-target b/tests/tcg/arm/Makefile.softmmu-target
>> new file mode 100644
>> index 0000000000..49d48d8a1c
>> --- /dev/null
>> +++ b/tests/tcg/arm/Makefile.softmmu-target
>> @@ -0,0 +1,29 @@
>> +# -*- Mode: makefile -*-
>> +#
>> +# ARM SoftMMU tests - included from tests/tcg/Makefile
>> +#
>> +
>> +ifeq ($(TARGET_ABI_DIR),arm)
>> +
>> +ARM_SRC=$(SRC_PATH)/tests/tcg/arm
>> +
>> +# Set search path for all sources
>> +VPATH 		+= $(ARM_SRC)
>> +
>> +ARM_TESTS=test-armv6m-undef
>> +
>> +TESTS += $(ARM_TESTS)
>> +
>> +CFLAGS+=-Wl,--build-id=none -x assembler-with-cpp
>> +LDFLAGS+=-nostdlib -N -static
>> +
>> +%: %.S %.ld
>> +	$(CC) $(CFLAGS) $(ASFLAGS) $< -o $@ $(LDFLAGS) -T $(ARM_SRC)/$@.ld
>> +
>> +# Specific Test Rules
>> +
>> +test-armv6m-undef: EXTRA_CFLAGS+=-mcpu=cortex-m0
>> +
>> +run-test-armv6m-undef: QEMU_OPTS+=-semihosting -M microbit -kernel
>> +
>> +endif
>> diff --git a/tests/tcg/arm/test-armv6m-undef.S b/tests/tcg/arm/test-armv6m-undef.S
>> new file mode 100644
>> index 0000000000..d18ca56b4a
>> --- /dev/null
>> +++ b/tests/tcg/arm/test-armv6m-undef.S
>> @@ -0,0 +1,154 @@
>> +/*
>> + * Test ARMv6-M UNDEFINED 32-bit instructions
>> + *
>> + * Copyright 2018 Red Hat Inc.
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2
>> + * or later. See the COPYING file in the top-level directory.
>> + */
>> +
>> +/*
>> + * Test that UNDEFINED 32-bit instructions fault as expected.  This is an
>> + * interesting test because ARMv6-M shares code with its more fully-featured
>> + * siblings and it's necessary to verify that its limited instruction set is
>> + * emulated correctly.
>> + *
>> + * The emulator must be invoked with -semihosting so that the test case can
>> + * terminate with exit code 0 on success or 1 on failure.
>> + *
>> + * Failures can be debugged with -d in_asm,int,exec,cpu and the
>> + * gdbstub (-S -s).
>> + */
>> +
>> +.syntax unified
>> +.cpu cortex-m0
>> +.thumb
>> +
>> +/*
>> + * Memory map
>> + */
>> +#define SRAM_BASE 0x20000000
>> +#define SRAM_SIZE (16 * 1024)
>> +
>> +/*
>> + * Semihosting interface on ARM T32
>> + * See "Semihosting for AArch32 and AArch64 Version 2.0 Documentation" by ARM
>> + */
>> +#define semihosting_call bkpt 0xab
>> +#define SYS_EXIT 0x18
>> +
>> +vector_table:
>> +    .word SRAM_BASE + SRAM_SIZE /* 0. SP_main */
>> +    .word exc_reset_thumb       /* 1. Reset */
>> +    .word 0                     /* 2. NMI */
>> +    .word exc_hard_fault_thumb  /* 3. HardFault */
>> +    .rept 7
>> +    .word 0                     /* 4-10. Reserved */
>> +    .endr
>> +    .word 0                     /* 11. SVCall */
>> +    .word 0                     /* 12. Reserved */
>> +    .word 0                     /* 13. Reserved */
>> +    .word 0                     /* 14. PendSV */
>> +    .word 0                     /* 15. SysTick */
>> +    .rept 32
>> +    .word 0                     /* 16-47. External Interrupts */
>> +    .endr
>> +
>> +exc_reset:
>> +.equ exc_reset_thumb, exc_reset + 1
>> +.global exc_reset_thumb
>> +    /* The following 32-bit UNDEFINED instructions are tested by executing
>> +     * them.  The HardFault exception handler should execute and return to
>> +     * the next test case.  If no exception is raised the test fails.
>> +     */
>> +
>> +    /* Table A5-9 32-bit Thumb encoding */
>> +    .short 0b1110100000000000
>> +    .short 0b0000000000000000
>> +    b not_reached
>> +    .short 0b1110100000000000
>> +    .short 0b1000000000000000
>> +    b not_reached
>> +    .short 0b1111100000000000
>> +    .short 0b0000000000000000
>> +    b not_reached
>> +    .short 0b1111100000000000
>> +    .short 0b1000000000000000
>> +    b not_reached
>> +    .short 0b1111000000000000
>> +    .short 0b0000000000000000
>> +    b not_reached
>> +
>> +    /* Table A5-10 Branch and miscellaneous control instructions */
>> +    .short 0b1111011111110000
>> +    .short 0b1010000000000000
>> +    b not_reached
>> +
>> +    /* The following are valid 32-bit instructions that must not raise a
>> +     * HardFault.
>> +     */
>> +
>> +    /* B4.2.3 Move to Special Register (moves to IPSR are ignored) */
>> +    msr ipsr, r0
>> +    b 1f
>> +    b not_reached
>> +1:
>> +    /* B4.2.2 Move from Special Register */
>> +    mrs r0, ipsr
>> +    b 1f
>> +    b not_reached
>> +1:
>> +    /* A6.7.13 Branch with Link (immediate) */
>> +    bl 1f
>> +1:
>> +    b 1f
>> +    b not_reached
>> +1:
>> +    /* A6.7.21 Data Memory Barrier */
>> +    dmb
>> +    b 1f
>> +    b not_reached
>> +1:
>> +    /* A6.7.22 Data Synchronization Barrier */
>> +    dsb
>> +    b 1f
>> +    b not_reached
>> +1:
>> +    /* A6.7.24 Instruction Memory Barrier */
>> +    isb
>> +    b 1f
>> +    b not_reached
>> +1:
>> +
>> +    /* Success! */
>> +    movs r0, 1
>> +    b exit
>> +
>> +not_reached: /* Failure :( */
>> +    movs r0, 0
>> +    b exit
>> +
>> +/* When a HardFault occurs, return to pc+6 (test cases are 3 halfwords long) */
>> +exc_hard_fault:
>> +.equ exc_hard_fault_thumb, exc_hard_fault + 1
>> +.global exc_hard_fault_thumb
>> +    ldr r0, [sp, 0x18]
>> +    adds r0, 6
>> +    str r0, [sp, 0x18]
>> +    bx lr
>> +
>> +/*
>> + * exit: Terminate emulator
>> + * @r0: 0 - failure, 1 - success
>> + */
>> +exit:
>> +    movs r1, 0
>> +    cmp r0, 1
>> +    bne 1f
>> +    ldr r1, ADP_Stopped_ApplicationExit
>> +1:
>> +    movs r0, SYS_EXIT
>> +    semihosting_call
>> +.align 2
>> +ADP_Stopped_ApplicationExit:
>> +    .word 0x20026
>> diff --git a/tests/tcg/arm/test-armv6m-undef.ld b/tests/tcg/arm/test-armv6m-undef.ld
>> new file mode 100644
>> index 0000000000..43dbbf17d5
>> --- /dev/null
>> +++ b/tests/tcg/arm/test-armv6m-undef.ld
>> @@ -0,0 +1,21 @@
>> +ENTRY(exc_reset_thumb)
>> +
>> +SECTIONS
>> +{
>> +    . = 0x0;
>> +    .text : {
>> +        *(.text)
>> +    }
>> +    .data : {
>> +        *(.data)
>> +    }
>> +    .rodata : {
>> +        *(.rodata)
>> +    }
>> +    .bss : {
>> +        *(.bss)
>> +    }
>> +    /DISCARD/ : {
>> +        *(.ARM.attributes)
>> +    }
>> +}
>>


--
Alex Bennée