Not sure how much benefit it provides, but any chance we could get ROM division support on chips that support it (like the LPC11U24)? I had it working in LPCXpresso before I switched to the online compiler, and it was pretty easy to enable. In fact, the new versions of LPCXpresso hide it behind a single checkbox in the project wizard, no work necessary! I've attached the relevant files from an LPCXpresso v6.0.4 project for reference sake:
AEABI Patch
//*****************************************************************************
// aeabi_romdiv_patch.s
// - Provides "patch" versions of the aeabi integer divide functions to
// replace the standard ones pulled in from the C library, which vector
// integer divides onto the rom division functions contained in
// specific NXP MCUs such as LPC11Uxx and LPC12xx.
// - Note that this patching will only occur if "__USE_ROMDIVIDE" is
// defined for the project build for both the compiler and assembler.
//*****************************************************************************
//
// Copyright(C) NXP Semiconductors, 2013
// All rights reserved.
//
// Software that is described herein is for illustrative purposes only
// which provides customers with programming information regarding the
// LPC products. This software is supplied "AS IS" without any warranties of
// any kind, and NXP Semiconductors and its licensor disclaim any and
// all warranties, express or implied, including all implied warranties of
// merchantability, fitness for a particular purpose and non-infringement of
// intellectual property rights. NXP Semiconductors assumes no responsibility
// or liability for the use of the software, conveys no license or rights under any
// patent, copyright, mask work right, or any other intellectual property rights in
// or to any products. NXP Semiconductors reserves the right to make changes
// in the software without notification. NXP Semiconductors also makes no
// representation or warranty that such application will be suitable for the
// specified use without further testing or modification.
//
// Permission to use, copy, modify, and distribute this software and its
// documentation is hereby granted, under NXP Semiconductors' and its
// licensor's relevant copyrights in the software, without fee, provided that it
// is used in conjunction with NXP Semiconductors microcontrollers. This
// copyright, permission, and disclaimer notice must appear in all copies of
// this code.
//*****************************************************************************
#if defined(__USE_ROMDIVIDE)
// Note that the romdivide "divmod" functions are not actually called from
// the below code, as these functions are actually just wrappers to the
// main romdivide "div" functions which push the quotient and remainder onto
// the stack, so as to be compatible with the way that C returns structures.
//
// This is not needed for the aeabi "divmod" functions, as the compiler
// automatically generates code that handles the return values being passed
// back in registers when it generates inline calls to __aeabi_idivmod and
// __aeabi_uidivmod routines.
.syntax unified
.text
// ========= __aeabi_idiv & __aeabi_idivmod =========
.align 2
.section .text.__aeabi_idiv
.global __aeabi_idiv
.set __aeabi_idivmod, __aeabi_idiv // make __aeabi_uidivmod an alias
.global __aeabi_idivmod
.global pDivRom_idiv // pointer to the romdivide 'idiv' functione
.func
.thumb_func
.type __aeabi_idiv, %function
__aeabi_idiv:
push {r4, lr}
ldr r3, =pDivRom_idiv
ldr r3, [r3, #0] // Load address of function
blx r3 // Call divide function
pop {r4, pc}
.endfunc
// ======== __aeabi_uidiv & __aeabi_uidivmod ========
.align 2
.section .text.__aeabi_uidiv
.global __aeabi_uidiv
.set __aeabi_uidivmod, __aeabi_uidiv // make __aeabi_uidivmod an alias
.global __aeabi_uidivmod
.global pDivRom_uidiv // pointer to the romdivide 'uidiv' function
.func
.thumb_func
.type __aeabi_uidiv, %function
__aeabi_uidiv:
push {r4, lr}
ldr r3, =pDivRom_uidiv
ldr r3, [r3, #0] // Load address of function
blx r3 // Call divide function
pop {r4, pc}
.endfunc
#endif // (__USE_ROMDIVIDE)
Modified Startup File
//*****************************************************************************
// LPC11Uxx Microcontroller Startup code for use with LPCXpresso IDE
//
// Version : 130808
//*****************************************************************************
//
// Copyright(C) NXP Semiconductors, 2013
// All rights reserved.
//
// Software that is described herein is for illustrative purposes only
// which provides customers with programming information regarding the
// LPC products. This software is supplied "AS IS" without any warranties of
// any kind, and NXP Semiconductors and its licensor disclaim any and
// all warranties, express or implied, including all implied warranties of
// merchantability, fitness for a particular purpose and non-infringement of
// intellectual property rights. NXP Semiconductors assumes no responsibility
// or liability for the use of the software, conveys no license or rights under any
// patent, copyright, mask work right, or any other intellectual property rights in
// or to any products. NXP Semiconductors reserves the right to make changes
// in the software without notification. NXP Semiconductors also makes no
// representation or warranty that such application will be suitable for the
// specified use without further testing or modification.
//
// Permission to use, copy, modify, and distribute this software and its
// documentation is hereby granted, under NXP Semiconductors' and its
// licensor's relevant copyrights in the software, without fee, provided that it
// is used in conjunction with NXP Semiconductors microcontrollers. This
// copyright, permission, and disclaimer notice must appear in all copies of
// this code.
//*****************************************************************************
#if defined (__cplusplus)
#ifdef __REDLIB__
#error Redlib does not support C++
#else
//*****************************************************************************
//
// The entry point for the C++ library startup
//
//*****************************************************************************
extern "C" {
extern void __libc_init_array(void);
}
#endif
#endif
#define WEAK __attribute__ ((weak))
#define ALIAS(f) __attribute__ ((weak, alias (#f)))
#if defined (__USE_CMSIS) || defined (__USE_LPCOPEN)
void SystemInit(void);
#endif
// Patch the AEABI integer divide functions to use MCU's romdivide library
#ifdef __USE_ROMDIVIDE
// Location in memory that holds the address of the ROM Driver table
#define PTR_ROM_DRIVER_TABLE ((unsigned int *)(0x1FFF1FF8))
// Variables to store addresses of idiv and udiv functions within MCU ROM
unsigned int *pDivRom_idiv;
unsigned int *pDivRom_uidiv;
#endif
//*****************************************************************************
#if defined (__cplusplus)
extern "C" {
#endif
//*****************************************************************************
//
// Forward declaration of the default handlers. These are aliased.
// When the application defines a handler (with the same name), this will
// automatically take precedence over these weak definitions
//
//*****************************************************************************
void ResetISR(void);
WEAK void NMI_Handler(void);
WEAK void HardFault_Handler(void);
WEAK void SVC_Handler(void);
WEAK void PendSV_Handler(void);
WEAK void SysTick_Handler(void);
WEAK void IntDefaultHandler(void);
//*****************************************************************************
//
// Forward declaration of the specific IRQ handlers. These are aliased
// to the IntDefaultHandler, which is a 'forever' loop. When the application
// defines a handler (with the same name), this will automatically take
// precedence over these weak definitions
//
//*****************************************************************************
void FLEX_INT0_IRQHandler (void) ALIAS(IntDefaultHandler);
void FLEX_INT1_IRQHandler (void) ALIAS(IntDefaultHandler);
void FLEX_INT2_IRQHandler (void) ALIAS(IntDefaultHandler);
void FLEX_INT3_IRQHandler (void) ALIAS(IntDefaultHandler);
void FLEX_INT4_IRQHandler (void) ALIAS(IntDefaultHandler);
void FLEX_INT5_IRQHandler (void) ALIAS(IntDefaultHandler);
void FLEX_INT6_IRQHandler (void) ALIAS(IntDefaultHandler);
void FLEX_INT7_IRQHandler (void) ALIAS(IntDefaultHandler);
void GINT0_IRQHandler (void) ALIAS(IntDefaultHandler);
void GINT1_IRQHandler (void) ALIAS(IntDefaultHandler);
void SSP1_IRQHandler (void) ALIAS(IntDefaultHandler);
void I2C_IRQHandler (void) ALIAS(IntDefaultHandler);
void TIMER16_0_IRQHandler (void) ALIAS(IntDefaultHandler);
void TIMER16_1_IRQHandler (void) ALIAS(IntDefaultHandler);
void TIMER32_0_IRQHandler (void) ALIAS(IntDefaultHandler);
void TIMER32_1_IRQHandler (void) ALIAS(IntDefaultHandler);
void SSP0_IRQHandler (void) ALIAS(IntDefaultHandler);
void UART_IRQHandler (void) ALIAS(IntDefaultHandler);
void USB_IRQHandler (void) ALIAS(IntDefaultHandler);
void USB_FIQHandler (void) ALIAS(IntDefaultHandler);
void ADC_IRQHandler (void) ALIAS(IntDefaultHandler);
void WDT_IRQHandler (void) ALIAS(IntDefaultHandler);
void BOD_IRQHandler (void) ALIAS(IntDefaultHandler);
void FMC_IRQHandler (void) ALIAS(IntDefaultHandler);
void USBWakeup_IRQHandler (void) ALIAS(IntDefaultHandler);
//*****************************************************************************
// The entry point for the application.
// __main() is the entry point for redlib based applications
// main() is the entry point for newlib based applications
//*****************************************************************************
#if defined (__REDLIB__)
extern void __main(void);
#else
extern int main(void);
#endif
//*****************************************************************************
//
// External declaration for the pointer to the stack top from the Linker Script
//
//*****************************************************************************
extern void _vStackTop(void);
//*****************************************************************************
#if defined (__cplusplus)
} // extern "C"
#endif
//*****************************************************************************
//
// The vector table. Note that the proper constructs must be placed on this to
// ensure that it ends up at physical address 0x0000.0000.
//
//*****************************************************************************
extern void (* const g_pfnVectors[])(void);
__attribute__ ((section(".isr_vector")))
void (* const g_pfnVectors[])(void) = {
&_vStackTop, // The initial stack pointer
ResetISR, // The reset handler
NMI_Handler, // The NMI handler
HardFault_Handler, // The hard fault handler
0, // Reserved
0, // Reserved
0, // Reserved
0, // Reserved
0, // Reserved
0, // Reserved
0, // Reserved
SVC_Handler, // SVCall handler
0, // Reserved
0, // Reserved
PendSV_Handler, // The PendSV handler
SysTick_Handler, // The SysTick handler
// LPC11U specific handlers
FLEX_INT0_IRQHandler, // 0 - GPIO pin interrupt 0
FLEX_INT1_IRQHandler, // 1 - GPIO pin interrupt 1
FLEX_INT2_IRQHandler, // 2 - GPIO pin interrupt 2
FLEX_INT3_IRQHandler, // 3 - GPIO pin interrupt 3
FLEX_INT4_IRQHandler, // 4 - GPIO pin interrupt 4
FLEX_INT5_IRQHandler, // 5 - GPIO pin interrupt 5
FLEX_INT6_IRQHandler, // 6 - GPIO pin interrupt 6
FLEX_INT7_IRQHandler, // 7 - GPIO pin interrupt 7
GINT0_IRQHandler, // 8 - GPIO GROUP0 interrupt
GINT1_IRQHandler, // 9 - GPIO GROUP1 interrupt
0, // 10 - Reserved
0, // 11 - Reserved
0, // 12 - Reserved
0, // 13 - Reserved
SSP1_IRQHandler, // 14 - SPI/SSP1 Interrupt
I2C_IRQHandler, // 15 - I2C0
TIMER16_0_IRQHandler, // 16 - CT16B0 (16-bit Timer 0)
TIMER16_1_IRQHandler, // 17 - CT16B1 (16-bit Timer 1)
TIMER32_0_IRQHandler, // 18 - CT32B0 (32-bit Timer 0)
TIMER32_1_IRQHandler, // 19 - CT32B1 (32-bit Timer 1)
SSP0_IRQHandler, // 20 - SPI/SSP0 Interrupt
UART_IRQHandler, // 21 - UART0
USB_IRQHandler, // 22 - USB IRQ
USB_FIQHandler, // 23 - USB FIQ
ADC_IRQHandler, // 24 - ADC (A/D Converter)
WDT_IRQHandler, // 25 - WDT (Watchdog Timer)
BOD_IRQHandler, // 26 - BOD (Brownout Detect)
FMC_IRQHandler, // 27 - IP2111 Flash Memory Controller
0, // 28 - Reserved
0, // 29 - Reserved
USBWakeup_IRQHandler, // 30 - USB wake-up interrupt
0, // 31 - Reserved
};
//*****************************************************************************
// Functions to carry out the initialization of RW and BSS data sections. These
// are written as separate functions rather than being inlined within the
// ResetISR() function in order to cope with MCUs with multiple banks of
// memory.
//*****************************************************************************
__attribute__ ((section(".after_vectors")))
void data_init(unsigned int romstart, unsigned int start, unsigned int len) {
unsigned int *pulDest = (unsigned int*) start;
unsigned int *pulSrc = (unsigned int*) romstart;
unsigned int loop;
for (loop = 0; loop < len; loop = loop + 4)
*pulDest++ = *pulSrc++;
}
__attribute__ ((section(".after_vectors")))
void bss_init(unsigned int start, unsigned int len) {
unsigned int *pulDest = (unsigned int*) start;
unsigned int loop;
for (loop = 0; loop < len; loop = loop + 4)
*pulDest++ = 0;
}
//*****************************************************************************
// The following symbols are constructs generated by the linker, indicating
// the location of various points in the "Global Section Table". This table is
// created by the linker via the Code Red managed linker script mechanism. It
// contains the load address, execution address and length of each RW data
// section and the execution and length of each BSS (zero initialized) section.
//*****************************************************************************
extern unsigned int __data_section_table;
extern unsigned int __data_section_table_end;
extern unsigned int __bss_section_table;
extern unsigned int __bss_section_table_end;
//*****************************************************************************
// Reset entry point for your code.
// Sets up a simple runtime environment and initializes the C/C++
// library.
//*****************************************************************************
__attribute__ ((section(".after_vectors")))
void
ResetISR(void) {
//
// Copy the data sections from flash to SRAM.
//
unsigned int LoadAddr, ExeAddr, SectionLen;
unsigned int *SectionTableAddr;
// Load base address of Global Section Table
SectionTableAddr = &__data_section_table;
// Copy the data sections from flash to SRAM.
while (SectionTableAddr < &__data_section_table_end) {
LoadAddr = *SectionTableAddr++;
ExeAddr = *SectionTableAddr++;
SectionLen = *SectionTableAddr++;
data_init(LoadAddr, ExeAddr, SectionLen);
}
// At this point, SectionTableAddr = &__bss_section_table;
// Zero fill the bss segment
while (SectionTableAddr < &__bss_section_table_end) {
ExeAddr = *SectionTableAddr++;
SectionLen = *SectionTableAddr++;
bss_init(ExeAddr, SectionLen);
}
// Patch the AEABI integer divide functions to use MCU's romdivide library
#ifdef __USE_ROMDIVIDE
// Get address of Integer division routines function table in ROM
unsigned int *div_ptr = (unsigned int *)((unsigned int *)*(PTR_ROM_DRIVER_TABLE))[4];
// Get addresses of integer divide routines in ROM
// These address are then used by the code in aeabi_romdiv_patch.s
pDivRom_idiv = (unsigned int *)div_ptr[0];
pDivRom_uidiv = (unsigned int *)div_ptr[1];
#endif
#if defined (__USE_CMSIS) || defined (__USE_LPCOPEN)
SystemInit();
#endif
#if defined (__cplusplus)
//
// Call C++ library initialisation
//
__libc_init_array();
#endif
#if defined (__REDLIB__)
// Call the Redlib library, which in turn calls main()
__main() ;
#else
main();
#endif
//
// main() shouldn't return, but if it does, we'll just enter an infinite loop
//
while (1) {
;
}
}
//*****************************************************************************
// Default exception handlers. Override the ones here by defining your own
// handler routines in your application code.
//*****************************************************************************
__attribute__ ((section(".after_vectors")))
void NMI_Handler(void)
{
while(1)
{
}
}
__attribute__ ((section(".after_vectors")))
void HardFault_Handler(void)
{
while(1)
{
}
}
__attribute__ ((section(".after_vectors")))
void SVC_Handler(void)
{
while(1)
{
}
}
__attribute__ ((section(".after_vectors")))
void PendSV_Handler(void)
{
while(1)
{
}
}
__attribute__ ((section(".after_vectors")))
void SysTick_Handler(void)
{
while(1)
{
}
}
//*****************************************************************************
//
// Processor ends up here if an unexpected interrupt occurs or a specific
// handler is not present in the application code.
//
//*****************************************************************************
__attribute__ ((section(".after_vectors")))
void IntDefaultHandler(void)
{
while(1)
{
}
}
Not sure how much benefit it provides, but any chance we could get ROM division support on chips that support it (like the LPC11U24)? I had it working in LPCXpresso before I switched to the online compiler, and it was pretty easy to enable. In fact, the new versions of LPCXpresso hide it behind a single checkbox in the project wizard, no work necessary! I've attached the relevant files from an LPCXpresso v6.0.4 project for reference sake:
AEABI Patch
Modified Startup File