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tenbahttenbaht
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Merge branch 'fix4': optimize pinMode()
add an experimental version of pinMode() and a minimal test environment to compare the size of the compiled C version and a hand crafted assembler version. The C version compiles to 270 bytes and uses 8 bytes on the stack while the assembler version is only 147 bytes and uses 1 byte on the stack. The resulting function is not yet integrated into the regular Arduino core files.
2 parents ddecdd5 + 4fd88ad commit 6aa1baf

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‎docs/api/migration.md‎

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@@ -96,6 +96,8 @@ names. The preprocessor does not allow for variable macro names. That means
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`_Generic` would work with fixed name like `Serial`, but it wouldn't work
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for `SoftwareSerial` with no standard instance name.
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[This](https://mort.coffee/home/obscure-c-features/) is a good introduction
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into the use of `_Generic`.
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‎test/pinmode/Makefile‎

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BASENAME=$(shell basename $$(pwd))
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EXECUTEABLE=$(BASENAME).ihx
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#SDCCBASE=/usr/local
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SDCCBASE=/opt/sdcc
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BINDIR=$(SDCCBASE)/bin
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CC=$(BINDIR)/sdcc
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LD=$(BINDIR)/sdld
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SDBASE=../../sduino/hardware/sduino/stm8
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LIBBASE=$(SDBASE)/STM8S_StdPeriph_Driver
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SDUINO=$(SDBASE)/cores/sduino
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CPPFLAGS=-DF_CPU=16000000L -DSTM8S103 -Ddouble=float \
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-I. -I$(SDUINO) -I$(SDBASE)/variants/standard \
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-I$(LIBBASE)/inc -I$(LIBBASE)/src \
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-I$(SDCCBASE)/share/sdcc/include/
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CFLAGS= -mstm8 #--debug
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LDFLAGS=-L$(LIBBASE)/lib -L$(SDCCBASE)/share/sdcc/lib/stm8 -lSTM8S103
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SRCS=pinmode-c.c pinmode-asm.c main.c
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BUILDDIR=build
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OBJECTS=$(SRCS:%.c=$(BUILDDIR)/%.rel)
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.PHONY: all clean flash statistics sim
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all: $(EXECUTEABLE) statistics sim
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$(EXECUTEABLE): $(OBJECTS)
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$(CC) $(CFLAGS) $(LDFLAGS) $^ -o $@
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$(OBJECTS) : $(BUILDDIR)/%.rel : %.c
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mkdir -p $(BUILDDIR)
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$(CC) -c $(CPPFLAGS) $(CFLAGS) $^ -o $@
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flash: $(EXECUTABLE)
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stm8flash -cstlinkv2 -pstm8s103?3 -w $^
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readopt:
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stm8flash -c stlinkv2 -p stm8s103?3 -s opt -r opt.bin
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# lists the length of functions and constants defined in the primary source
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# file
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statistics: $(OBJECTS)
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cd $(BUILDDIR); awk '/ CODE/ {print FILENAME "\t" strtonum("0x"$$4)}' *.sym
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sim: $(EXECUTEABLE)
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@. ./sim
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# @. ./sim | grep "0x0001 00 00 00 00 00 00"
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# . ./sim | grep "0x0001 00 00 00 00 00 00" || echo "fail"
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# grep "[0-9] _" $(BASENAME).rst |\
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# awk 'BEGIN {print "length\tfunction\n------\t----------";}{ a=strtonum("0x"$$1);if (name) print a-s "\t" name; s=a; name=$$3}'
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clean:
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rm -rf *.lib *.rst *.rel *.lst *.ihx *.sym *.asm *.lk *.map \
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*.cdb *.adb *~ *.bak build
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rm -f $(EXECUTABLE)

‎test/pinmode/README.md‎

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original version (276 bytes)
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0080A0 47 _pinMode1:
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0081B4 268 _setup:
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0081BE 282 _loop:
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after first commit (176 bytes):
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0080A0 48 _pinMode1:
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0081B4 269 _pinMode_asm:
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008264 410 _setup:
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00826E 424 _loop:
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Reihenfolgen:
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INPUT |-CR2, -CR1, -DDR
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INPUT_PULLUP |-CR2, -DDR, +CR1
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OUTPUT_FAST |+CR1, +DDR, +CR2
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OUTPUT_OD_FAST |-CR1, +DDR, +CR2
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OUTPUT_OD |-CR1, -CR2, +DDR
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OUTPUT |+CR1, -CR2, +DDR
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mode CR2
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sstm8 -tS003 -S uart=1,port=10000 mini.ihx
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CR1: pullup bzw. open-drain
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CR2: in: INT, out: fast
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- input: als erstes reset
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- output: als letztes setzen (nach DDR)
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Schritt 1: CR2 (in: INT, out: fast)
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- set: OUTPUT_FAST, OUTPUT_OD_FAST
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- reset: sonst
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## Simulator
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-i m: info memory

‎test/pinmode/main.c‎

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/**
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* Test the optimized Versions of pinMode
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*
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* After each test the content of the GPIO registers is checked against
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* the expected values. The table results[] contains the number of mismatched
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* bytes after each test.
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*
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* Expected result: all bytes in results[] == 0x00
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*/
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#define ARDUINO_MAIN
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#include "Arduino.h"
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#include "stm8s_it.h"
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void pinMode_c(uint8_t pin, uint8_t mode);
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void pinMode_asm(uint8_t pin, uint8_t mode);
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// select which function should be used for the test
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#define pinMode_test pinMode_asm
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uint8_t results[6];
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/**
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* checks a memory area for an expected content
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*
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* @returns: number of mismatched bytes (0=ok)
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*/
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uint8_t checkresult(uint16_t adr, uint8_t *data)
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{
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uint8_t i,err;
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err = 0;
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for (i=0; i<3; ++i) {
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if (((uint8_t*)adr)[2+i] != data[i]) err++;
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}
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return err;
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}
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/**
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* fills a memory area with zeros
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*
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* The simulator does not clear the memory and does not properly
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* initialize the IO registers after reset. Use this instead.
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*/
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void _memset(unsigned char *adr, unsigned int cnt)
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{
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while (cnt--) *adr++=0;
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}
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void main(void)
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{
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unsigned char *r = results;
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_memset((unsigned char *)GPIOA_BaseAddress, 20);
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// expected result: xx xx 00 00 00
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pinMode_test(PA1,INPUT);
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*r++ = checkresult(GPIOA_BaseAddress, "\x00\x00\x00");
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// expected result: xx xx 20 20 00
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pinMode_test(PB5,OUTPUT);
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*r++ = checkresult(GPIOB_BaseAddress, "\x20\x20\x00");
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// expected result: xx xx 00 10 00
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pinMode_test(PC4,INPUT_PULLUP);
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*r++ = checkresult(GPIOC_BaseAddress, "\x00\x10\x00");
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// expected result: xx xx 20 10 00
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pinMode_test(PC5,OUTPUT_OD);
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*r++ = checkresult(GPIOC_BaseAddress, "\x20\x10\x00");
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// expected result: xx xx 02 02 02
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pinMode_test(PD1,OUTPUT_FAST);
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*r++ = checkresult(GPIOD_BaseAddress, "\x02\x02\x02");
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// expected result: xx xx 42 02 42
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pinMode_test(PD6,OUTPUT_OD_FAST);
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*r++ = checkresult(GPIOD_BaseAddress, "\x42\x02\x42");
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for(;;); // endless loop
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}
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/*
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* empty default IRQ functions to make the linker happy if the
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* respective module is not to linked.
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*/
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void UART1_TX_IRQHandler(void) __interrupt(ITC_IRQ_UART1_TX){}
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void UART1_RX_IRQHandler(void) __interrupt(ITC_IRQ_UART1_RX){}
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// define as __naked to avoid the "clr a/dix x,a" prolog
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#define IMPLEMENT_ISR(vect, interrupt) \
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void vect(void) __interrupt((interrupt)>>8) __naked { \
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__asm__("iret"); \
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}
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IMPLEMENT_ISR(EXTI_PORTA_IRQHandler, INT_PORTA) /* EXTI PORTA */
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IMPLEMENT_ISR(EXTI_PORTB_IRQHandler, INT_PORTB) /* EXTI PORTB */
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IMPLEMENT_ISR(EXTI_PORTC_IRQHandler, INT_PORTC) /* EXTI PORTC */
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IMPLEMENT_ISR(EXTI_PORTD_IRQHandler, INT_PORTD) /* EXTI PORTD */
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IMPLEMENT_ISR(EXTI_PORTE_IRQHandler, INT_PORTE) /* EXTI PORTE */
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IMPLEMENT_ISR(TIM1_CAP_COM_IRQHandler, INT_TIM1_CAPCOM)
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//IMPLEMENT_ISR(TIM1_UPD_OVF_TRG_BRK_IRQHandler, INT_TIM1_OVF)
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//IMPLEMENT_ISR(TIM2_CAP_COM_IRQHandler, INT_TIM2_CAPCOM)
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//IMPLEMENT_ISR(TIM2_UPD_OVF_TRG_BRK_IRQHandler, INT_TIM2_OVF)
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void TIM4_UPD_OVF_IRQHandler(void) __interrupt(ITC_IRQ_TIM4_OVF){}

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