[Arm] Align comments and spaces in crt0.S libgloss and sys/arm
Richard Earnshaw (lists)
Richard.Earnshaw@arm.com
Thu Apr 11 13:33:00 GMT 2019
On 11/04/2019 13:58, Alexander Fedotov wrote:
> Sorry. I have missed some lines in previous patch. Here is new one below.
>
> From 68d7a9bb5f11ddc3c0420560c718b6a2f8041896 Mon Sep 17 00:00:00 2001
> From: Alexander Fedotov <alfedotov@gmail.com>
> Date: Thu, 11 Apr 2019 15:28:05 +0300
> Subject: [PATCH] Align comments and spaces in libgloss/arm/crt0.S and
> newlib/libc/sys/arm/crt0.S to ease further code alignment.
>
> ---
> libgloss/arm/crt0.S | 131 ++++++++++++++++++-------------------
> newlib/libc/sys/arm/crt0.S | 12 ++--
> 2 files changed, 71 insertions(+), 72 deletions(-)
>
> diff --git a/libgloss/arm/crt0.S b/libgloss/arm/crt0.S
> index c708f63d8..e5c813e3b 100644
> --- a/libgloss/arm/crt0.S
> +++ b/libgloss/arm/crt0.S
> @@ -90,14 +90,14 @@
> #endif
> #endif
>
> -/* Start by setting up a stack */
> +/* Start by setting up a stack. */
> #ifdef ARM_RDP_MONITOR
> - /* Issue Demon SWI to read stack info */
> - swi SWI_GetEnv /* Returns command line in r0 */
> - mov sp,r1 /* and the highest memory address in r1 */
> + /* Issue Demon SWI to read stack info. */
> + swi SWI_GetEnv /* Returns command line in r0. */
> + mov sp,r1 /* and the highest memory address in r1. */
>
> - /* stack limit is at end of data */
> - /* allow slop for stack overflow handling and small frames */
> + /* Stack limit is at end of data. */
> + /* Allow slop for stack overflow handling and small frames. */
> #ifdef THUMB1_ONLY
> ldr r0, .LC2
> adds r0, #128
> @@ -109,19 +109,19 @@
> #endif
> #else
> #ifdef ARM_RDI_MONITOR
> - /* Issue Angel SWI to read stack info */
> + /* Issue Angel SWI to read stack info. */
> movs r0, #AngelSWI_Reason_HeapInfo
> - adr r1, .LC0 /* point at ptr to 4 words to receive data */
> + adr r1, .LC0 /* Point at ptr to 4 words to receive data. */
> #ifdef THUMB_VXM
> bkpt AngelSWI
> #elif defined(__thumb2__)
> - /* We are in thumb mode for startup on armv7 architectures. */
> + /* We are in thumb mode for startup on armv7 architectures. */
> AngelSWIAsm (AngelSWI)
> #else
> - /* We are always in ARM mode for startup on pre armv7 archs. */
> + /* We are always in ARM mode for startup on pre armv7 archs. */
> AngelSWIAsm (AngelSWI_ARM)
> #endif
> - ldr r0, .LC0 /* point at values read */
> + ldr r0, .LC0 /* Point at values read. */
>
> /* Set __heap_limit. */
> ldr r1, [r0, #4]
> @@ -148,14 +148,15 @@
> to skip setting sp/sl to 0 here.
> - Considering M-profile processors, We might want to initialize
> sp by the first entry of vector table and return 0 to SYS_HEAPINFO
> - semihosting call, which will be skipped here. */
> + semihosting call, which will be skipped here. */
> cmp r1, #0
> beq .LC26
> mov sp, r1
> .LC26:
> cmp r2, #0
> beq .LC27
> - /* allow slop for stack overflow handling and small frames */
> +
> + /* Allow slop for stack overflow handling and small frames. */
> #ifdef THUMB1_ONLY
> adds r2, #128
> adds r2, #128
> @@ -163,9 +164,10 @@
> #else
> add sl, r2, #256
> #endif
> +
> .LC27:
> #else
> - /* Set up the stack pointer to a fixed value */
> + /* Set up the stack pointer to a fixed value. */
> /* Changes by toralf:
> - Allow linker script to provide stack via __stack symbol - see
> defintion of .Lstack
> @@ -175,7 +177,7 @@
> Loosely based on init.s from ARM/Motorola example code.
> Note: Mode switch via CPSR is not allowed once in non-privileged
> mode, so we take care not to enter "User" to set up its sp,
> - and also skip most operations if already in that mode. */
> + and also skip most operations if already in that mode. */
>
> ldr r3, .Lstack
> cmp r3, #0
> @@ -192,42 +194,42 @@
> /* Note: This 'mov' is essential when starting in User, and ensures we
> always get *some* sp value for the initial mode, even if we
> have somehow missed it below (in which case it gets the same
> - value as FIQ - not ideal, but better than nothing.) */
> + value as FIQ - not ideal, but better than nothing). */
> mov sp, r3
> #ifdef PREFER_THUMB
> /* XXX Fill in stack assignments for interrupt modes. */
> #else
> mrs r2, CPSR
> - tst r2, #0x0F /* Test mode bits - in User of all are 0 */
> - beq .LC23 /* "eq" means r2 AND #0x0F is 0 */
> - msr CPSR_c, #0xD1 /* FIRQ mode, interrupts disabled */
> + tst r2, #0x0F /* Test mode bits - in User of all are 0. */
> + beq .LC23 /* "eq" means r2 AND #0x0F is 0. */
> + msr CPSR_c, #0xD1 /* FIRQ mode, interrupts disabled. */
> mov sp, r3
> - sub sl, sp, #0x1000 /* This mode also has its own sl (see below) */
> + sub sl, sp, #0x1000 /* This mode also has its own sl (see below). */
>
> mov r3, sl
> - msr CPSR_c, #0xD7 /* Abort mode, interrupts disabled */
> + msr CPSR_c, #0xD7 /* Abort mode, interrupts disabled. */
> mov sp, r3
> sub r3, r3, #0x1000
>
> - msr CPSR_c, #0xDB /* Undefined mode, interrupts disabled */
> + msr CPSR_c, #0xDB /* Undefined mode, interrupts disabled. */
> mov sp, r3
> sub r3, r3, #0x1000
>
> - msr CPSR_c, #0xD2 /* IRQ mode, interrupts disabled */
> + msr CPSR_c, #0xD2 /* IRQ mode, interrupts disabled. */
> mov sp, r3
> sub r3, r3, #0x2000
>
> - msr CPSR_c, #0xD3 /* Supervisory mode, interrupts disabled */
> + msr CPSR_c, #0xD3 /* Supervisory mode, interrupts disabled. */
>
> mov sp, r3
> - sub r3, r3, #0x8000 /* Min size 32k */
> - bic r3, r3, #0x00FF /* Align with current 64k block */
> + sub r3, r3, #0x8000 /* Min size 32k. */
> + bic r3, r3, #0x00FF /* Align with current 64k block. */
> bic r3, r3, #0xFF00
>
> str r3, [r3, #-4] /* Move value into user mode sp without */
> - ldmdb r3, {sp}^ /* changing modes, via '^' form of ldm */
> + ldmdb r3, {sp}^ /* changing modes, via '^' form of ldm. */
> orr r2, r2, #0xC0 /* Back to original mode, presumably SVC, */
> - msr CPSR_c, r2 /* with FIQ/IRQ disable bits forced to 1 */
> + msr CPSR_c, r2 /* with FIQ/IRQ disable bits forced to 1. */
> #endif
> .LC23:
> /* Setup a default stack-limit in-case the code has been
> @@ -243,24 +245,24 @@
> subs r2, r3, r2
> mov sl, r2
> #else
> - sub sl, r3, #64 << 10 /* Still assumes 256bytes below sl */
> + sub sl, r3, #64 << 10 /* Still assumes 256bytes below sl. */
> #endif
> #endif
> #endif
> /* Zero the memory in the .bss section. */
> - movs a2, #0 /* Second arg: fill value */
> - mov fp, a2 /* Null frame pointer */
> - mov r7, a2 /* Null frame pointer for Thumb */
> + movs a2, #0 /* Second arg: fill value. */
> + mov fp, a2 /* Null frame pointer. */
> + mov r7, a2 /* Null frame pointer for Thumb. */
>
> - ldr a1, .LC1 /* First arg: start of memory block */
> + ldr a1, .LC1 /* First arg: start of memory block. */
> ldr a3, .LC2
> - subs a3, a3, a1 /* Third arg: length of block */
> + subs a3, a3, a1 /* Third arg: length of block. */
>
>
> #if __thumb__ && !defined(PREFER_THUMB)
> - /* Enter Thumb mode.... */
> - add a4, pc, #1 /* Get the address of the Thumb block */
> - bx a4 /* Go there and start Thumb decoding */
> + /* Enter Thumb mode... */
> + add a4, pc, #1 /* Get the address of the Thumb block. */
> + bx a4 /* Go there and start Thumb decoding. */
>
> .code 16
> .global __change_mode
> @@ -271,9 +273,8 @@ __change_mode:
> bl FUNCTION (memset)
> #if !defined (ARM_RDP_MONITOR) && !defined (ARM_RDI_MONITOR)
> /* Changes by toralf: Taken from libgloss/m68k/crt0.S
> - * initialize target specific stuff. Only execute these
> - * functions it they exist.
> - */
> + initialize target specific stuff. Only execute these
> + functions it they exist. */
> ldr r3, .Lhwinit
> cmp r3, #0
> beq .LC24
> @@ -285,24 +286,24 @@ __change_mode:
> indirect_call r3
>
> .LC25:
> - movs r0, #0 /* no arguments */
> - movs r1, #0 /* no argv either */
> + movs r0, #0 /* No arguments. */
> + movs r1, #0 /* No argv either. */
> #else
> - /* Need to set up standard file handles */
> + /* Need to set up standard file handles. */
> bl FUNCTION (initialise_monitor_handles)
>
> #ifdef ARM_RDP_MONITOR
> - swi SWI_GetEnv /* sets r0 to point to the command line */
> + swi SWI_GetEnv /* Sets r0 to point to the command line. */
> movs r1, r0
> #else
> movs r0, #AngelSWI_Reason_GetCmdLine
> - ldr r1, .LC30 /* Space for command line */
> + ldr r1, .LC30 /* Space for command line. */
> AngelSWIAsm (AngelSWI)
> ldr r1, .LC30
> ldr r1, [r1]
> #endif
> - /* Parse string at r1 */
> - movs r0, #0 /* count of arguments so far */
> + /* Parse string at r1. */
> + movs r0, #0 /* Count of arguments so far. */
> /* Push a NULL argument onto the end of the list. */
> #ifdef __thumb__
> push {r0}
> @@ -310,7 +311,7 @@ __change_mode:
> stmfd sp!, {r0}
> #endif
> .LC10:
> -/* Skip leading blanks */
> +/* Skip leading blanks. */
> #ifdef __thumb__
> ldrb r3, [r1]
> adds r1, #1
> @@ -322,7 +323,7 @@ __change_mode:
> cmp r3, #' '
> beq .LC10
>
> -/* See whether we are scanning a string */
> +/* See whether we are scanning a string. */
> cmp r3, #'"'
> #ifdef __thumb__
> beq .LC20
> @@ -333,17 +334,17 @@ __change_mode:
> b .LC22
>
> .LC21:
> - movs r2, #' ' /* terminator type */
> - subs r1, r1, #1 /* adjust back to point at start char */
> + movs r2, #' ' /* Terminator type. */
> + subs r1, r1, #1 /* Adjust back to point at start char. */
> .LC22:
> #else
> cmpne r3, #'\''
> moveq r2, r3
> - movne r2, #' ' /* terminator type */
> - subne r1, r1, #1 /* adjust back to point at start char */
> + movne r2, #' ' /* Terminator type. */
> + subne r1, r1, #1 /* Adjust back to point at start char. */
> #endif
>
> -/* Stack a pointer to the current argument */
> +/* Stack a pointer to the current argument. */
> #ifdef __thumb__
> push {r1}
> #else
> @@ -359,16 +360,16 @@ __change_mode:
> #endif
> cmp r3, #0
> beq .LC12
> - cmp r2, r3 /* reached terminator? */
> + cmp r2, r3 /* Reached terminator ? */
> bne .LC11
> movs r2, #0
> subs r3, r1, #1
> - strb r2, [r3] /* terminate the arg string */
> + strb r2, [r3] /* Terminate the arg string. */
> b .LC10
>
> .LC12:
> - mov r1, sp /* point at stacked arg pointers */
> - /* We've now got the stacked args in order reverse the */
> + mov r1, sp /* Point at stacked arg pointers. */
> + /* We've now got the stacked args in order, reverse them. */
> #ifdef __thumb__
> movs r2, r0
> lsls r2, #2
> @@ -390,10 +391,10 @@ __change_mode:
> bics r4, r5
> mov sp, r4
> #else
> - add r2, sp, r0, LSL #2 /* End of args */
> - mov r3, sp /* Start of args */
> + add r2, sp, r0, LSL #2 /* End of args. */
> + mov r3, sp /* Start of args. */
> .LC13: cmp r2, r3
> - ldrhi r4,[r2, #-4] /* Reverse ends of list */
> + ldrhi r4,[r2, #-4] /* Reverse ends of list. */
> ldrhi r5, [r3]
> strhi r5, [r2, #-4]!
> strhi r4, [r3], #4
> @@ -431,7 +432,6 @@ __change_mode:
>
> #if __thumb__ && !defined(PREFER_THUMB)
> /* Come out of Thumb mode. This code should be redundant. */
> -
> mov a4, pc
> bx a4
>
> @@ -447,7 +447,6 @@ change_back:
>
> /* For Thumb, constants must be after the code since only
> positive offsets are supported for PC relative addresses. */
> -
> .align 0
> .LC0:
> #ifdef ARM_RDI_MONITOR
> @@ -457,13 +456,13 @@ change_back:
> /* Changes by toralf: Provide alternative "stack" variable whose value
> may be defined externally; .Lstack will be used instead of .LC0 if
> it points to a non-0 value. Also set up references to "hooks" that
> - may be used by the application to provide additional init code. */
> -
> + may be used by the application to provide additional init code. */
> #ifdef __pe__
> .word 0x800000
> #else
> .word 0x80000 /* Top of RAM on the PIE board. */
> #endif
> +
> .Lstack:
> .word __stack
> .Lhwinit:
> @@ -476,7 +475,7 @@ change_back:
> runtime (meaning "ignore setting") for the variables, when the user
> does not provide the symbols. (The linker uses a weak symbol if,
> and only if, a normal version of the same symbol isn't provided
> - e.g. by a linker script or another object file.) */
> + e.g. by a linker script or another object file). */
Style rules say that the full stop goes inside the parenthesis if the
entire sentence is parenthetical; otherwise it goes outside. So its
technically the other version that is incorrect.
>
> .weak __stack
> .weak FUNCTION (hardware_init_hook)
> diff --git a/newlib/libc/sys/arm/crt0.S b/newlib/libc/sys/arm/crt0.S
> index 64d425900..602148969 100644
> --- a/newlib/libc/sys/arm/crt0.S
> +++ b/newlib/libc/sys/arm/crt0.S
> @@ -50,13 +50,13 @@
> .global \name
> .thumb_func
> \name:
> -.endm
> +.endm
> #else
> .code 32
> .macro FUNC_START name
> - .global \name
> + .global \name
> \name:
> -.endm
> +.endm
> #endif
>
> .macro indirect_call reg
> @@ -399,7 +399,7 @@ __change_mode:
> bl FUNCTION (_init)
> movs r0, r4
> movs r1, r5
> -#endif
> +#endif
> bl FUNCTION (main)
>
> bl FUNCTION (exit) /* Should not return. */
> @@ -420,7 +420,7 @@ change_back:
> #endif
>
> /* For Thumb, constants must be after the code since only
> - positive offsets are supported for PC relative addresses. */
> + positive offsets are supported for PC relative addresses. */
> .align 0
> .LC0:
> #ifdef ARM_RDI_MONITOR
> @@ -430,7 +430,7 @@ change_back:
> /* Changes by toralf: Provide alternative "stack" variable whose value
> may be defined externally; .Lstack will be used instead of .LC0 if
> it points to a non-0 value. Also set up references to "hooks" that
> - may be used by the application to provide additional init
> code. */
> + may be used by the application to provide additional init code. */
> #ifdef __pe__
> .word 0x800000
> #else
>
Other than the comment above, this is fine. Thanks for doing this.
Do you have commit rights?
R.
More information about the Newlib
mailing list