e754a32842
default of -fguess-branch-probablility causes time optimizations (?) like rewriting `if (foo) x++;' as `if (!foo) goto forth; back: ; ...; forth: x++; goto back;". This is pessimizes space especially well on i386's because one short branch gets converted to 2 long ones. Removed -fno-align-foo since it is implied by -Os. Previous commit messages seem to have overstated the new alignment bugs in gcc. The only case that affects boot2 is that -fno-align-functions (or equivalently -falign-functions=1) actually gives -falign-functions=2. This is caused by FUNCTION_BOUNDARY being 2 (bytes) instead of 1. The default case where the optimization level is 1 and no alignment options are given is more broken. All alignments are minimal, modulo the bug in FUNCTION_BOUNDARY. This is caused by toplev.c setting defaults too early. Some hacks in previous commits ar not needed now, but may as well be kept until gcc is fixed. The previous on in the Makefile saved 96 bytes of text due to the wrong FUNCTION_BOUNDARY and 32 bytes of data due to unrelated bloat in the alignment of large objects. There aren't even any options to control alignment of data.
94 lines
2.3 KiB
Makefile
94 lines
2.3 KiB
Makefile
# $FreeBSD$
|
|
|
|
PROG= boot2
|
|
NOMAN=
|
|
STRIP=
|
|
BINDIR?= /boot
|
|
BINMODE= 444
|
|
CLEANFILES+= boot1 boot1.out boot1.o \
|
|
boot2.ldr boot2.bin boot2.ld boot2.out boot2.o boot2.h \
|
|
sio.o
|
|
|
|
NM?= nm
|
|
|
|
# A value of 0x80 enables LBA support.
|
|
B1FLAGS= 0x80
|
|
|
|
BOOT_COMCONSOLE_PORT?= 0x3f8
|
|
BOOT_COMCONSOLE_SPEED?= 9600
|
|
B2SIOFMT?= 0x3
|
|
|
|
.if exists(${.OBJDIR}/../btx)
|
|
BTX= ${.OBJDIR}/../btx
|
|
.else
|
|
BTX= ${.CURDIR}/../btx
|
|
.endif
|
|
|
|
ORG1= 0x7c00
|
|
ORG2= 0x1000
|
|
|
|
CFLAGS= -elf -ffreestanding -Os -fno-builtin \
|
|
-fno-guess-branch-probability \
|
|
-mrtd \
|
|
-I${.CURDIR}/../btx/lib -I. \
|
|
-Wall -Waggregate-return -Wbad-function-cast -Wcast-align \
|
|
-Wmissing-declarations -Wmissing-prototypes -Wnested-externs \
|
|
-Wpointer-arith -Wshadow -Wstrict-prototypes -Wwrite-strings
|
|
|
|
LDFLAGS=-nostdlib -static -N
|
|
|
|
all: boot1 boot2
|
|
|
|
boot1: boot1.out
|
|
objcopy -S -O binary boot1.out ${.TARGET}
|
|
|
|
boot1.out: boot1.o
|
|
${LD} ${LDFLAGS} -e start -Ttext ${ORG1} -o ${.TARGET} boot1.o
|
|
|
|
boot1.o: boot1.s
|
|
${AS} ${AFLAGS} --defsym FLAGS=${B1FLAGS} ${.IMPSRC} -o ${.TARGET}
|
|
|
|
boot2.o: boot2.c
|
|
${CC} ${CFLAGS} -S -o boot2.s.tmp ${.IMPSRC}
|
|
sed -e '/align/d' -e '/nop/d' < boot2.s.tmp > boot2.s
|
|
rm -f boot2.s.tmp
|
|
${AS} ${AFLAGS} -o boot2.o boot2.s
|
|
|
|
boot2.h: boot1.out
|
|
${NM} -t d ${.ALLSRC} | awk '/([0-9])+ T xread/ \
|
|
{ x = $$1 - ORG1; printf("#define XREADORG 0x7%x\n", x) }' \
|
|
ORG1=`printf "%d" ${ORG1}` > boot2.h
|
|
|
|
boot2: boot2.ldr boot2.bin ${BTX}/btx/btx
|
|
btxld -v -E ${ORG2} -f bin -b ${BTX}/btx/btx -l boot2.ldr \
|
|
-o boot2.ld -P 1 boot2.bin
|
|
@ls -l boot2.ld | awk '{ x = 7680 - $$5; \
|
|
print x " bytes available"; if (x < 0) exit 1 }'
|
|
dd if=boot2.ld of=${.TARGET} obs=7680 conv=osync 2>/dev/null
|
|
|
|
boot2.ldr:
|
|
dd if=/dev/zero of=${.TARGET} bs=512 count=1 2>/dev/null
|
|
|
|
boot2.bin: boot2.out
|
|
objcopy -S -O binary boot2.out ${.TARGET}
|
|
|
|
boot2.out: boot2.o sio.o
|
|
${LD} ${LDFLAGS} -Ttext ${ORG2} -o ${.TARGET} \
|
|
${BTX}/lib/crt0.o boot2.o sio.o
|
|
|
|
boot2.o: boot2.h
|
|
|
|
sio.o: sio.s
|
|
${AS} ${AFLAGS} --defsym SIOPRT=${BOOT_COMCONSOLE_PORT} \
|
|
--defsym SIOFMT=${B2SIOFMT} \
|
|
--defsym SIOSPD=${BOOT_COMCONSOLE_SPEED} \
|
|
${.IMPSRC} -o ${.TARGET}
|
|
|
|
install:
|
|
${INSTALL} ${COPY} -o ${BINOWN} -g ${BINGRP} -m ${BINMODE} \
|
|
boot1 ${DESTDIR}${BINDIR}/boot1
|
|
${INSTALL} ${COPY} -o ${BINOWN} -g ${BINGRP} -m ${BINMODE} \
|
|
boot2 ${DESTDIR}${BINDIR}/boot2
|
|
|
|
.include <bsd.prog.mk>
|