cosmopolitan/build/compile
Justine Tunney f4f4caab0e Add x86_64-linux-gnu emulator
I wanted a tiny scriptable meltdown proof way to run userspace programs
and visualize how program execution impacts memory. It helps to explain
how things like Actually Portable Executable works. It can show you how
the GCC generated code is going about manipulating matrices and more. I
didn't feel fully comfortable with Qemu and Bochs because I'm not smart
enough to understand them. I wanted something like gVisor but with much
stronger levels of assurances. I wanted a single binary that'll run, on
all major operating systems with an embedded GPL barrier ZIP filesystem
that is tiny enough to transpile to JavaScript and run in browsers too.

https://justine.storage.googleapis.com/emulator625.mp4
2020-08-25 04:43:42 -07:00

285 lines
6.9 KiB
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#-*-mode:sh;indent-tabs-mode:nil;tab-width:2;coding:utf-8-*-┐
#───vi: set net ft=sh ts=2 sts=2 fenc=utf-8 :vi─────────────┘
#
# OVERVIEW
#
# GNU/LLVM Compiler Frontend Frontend
#
# DESCRIPTION
#
# This wrapper script filters out certain flags so the compiler won't
# whine, and passes extra information to the preprocessor.
#
# EXAMPLE
#
# build/compile cc -o program program.c
if [ ! -d o/third_party/gcc ]; then
third_party/gcc/unbundle.sh
fi
if [ "$1" = "clang-10" ]; then
if ! command -v clang-10 >/dev/null; then
shift
set -- o/third_party/gcc/bin/x86_64-linux-musl-gcc "$@"
fi
fi
if [ "$1" = "clang++-10" ]; then
if ! command -v clang++-10 >/dev/null; then
shift
set -- o/third_party/gcc/bin/x86_64-linux-musl-g++ "$@"
fi
fi
export LC_ALL=C
MKDIR=${MKDIR:-$(command -v mkdir) -p} || exit
GZME=
PLAT="${1%% *}"
FDIAGNOSTIC_COLOR=
CCNAME=${CCNAME:-gcc}
CCVERSION=${CCVERSION:-4}
COUNTERMAND=
# The GNU Compiler Collection passes a lot of CFLAGS to the preprocessor
# (which we call CCFLAGS) but it should pass more; and we do just that.
FIRST=1
OUTARG=0
INVISIBLE=0
for x; do
if [ $FIRST -eq 1 ]; then
set --
FIRST=0
fi
if [ $OUTARG -eq 1 ]; then
OUTARG=0
OUT="$x"
fi
case "$x" in
-o)
set -- "$@" "$x"
OUTARG=1
;;
-w)
set -- "$@" "$x" -D__W__
;;
-pg)
if [ $INVISIBLE -eq 0 ]; then
set -- "$@" "$x" -D__PG__ # @see libc/macros.h
fi
;;
-mfentry)
if [ $INVISIBLE -eq 0 ]; then
set -- "$@" "$x" -D__MFENTRY__
fi
;;
-fomit-frame-pointer)
INVISIBLE=1
set -- "$@" "$x"
;;
-mno-vzeroupper)
set -- "$@" "$x" -Wa,-msse2avx -D__MNO_VZEROUPPER__
;;
-fsanitize=undefined)
set -- "$@" "$x" -D__FSANITIZE_UNDEFINED__
COUNTERMAND="$COUNTERMAND -fno-data-sections" # sqlite.o
;;
-mnop-mcount)
if [ "$CCNAME" = "gcc" ] && [ "$CCVERSION" -ge 6 ]; then
set -- "$@" "$x" -D__MNOP_MCOUNT__
fi
;;
-mrecord-mcount)
if [ "$CCNAME" = "gcc" ] && [ "$CCVERSION" -ge 6 ]; then
set -- "$@" "$x" -D__MRECORD_MCOUNT__
fi
;;
-fsanitize=implicit*integer*)
if ! [ "$CCNAME" = "gcc" ]; then
set -- "$@" "$x"
fi
;;
-f*sanitize*|-gz*|-*stack-protector*|-fvect-cost*|-mstringop*)
if [ "$CCNAME" = "gcc" ] && [ "$CCVERSION" -ge 6 ]; then
set -- "$@" "$x"
fi
;;
-freorder-blocks-and-partition|-fstack-clash-protection)
if [ "$CCNAME" = "gcc" ] && [ "$CCVERSION" -ge 8 ]; then
set -- "$@" "$x"
fi
;;
-fdiagnostic-color=*)
FDIAGNOSTIC_COLOR=$x
;;
-fopt-info*=*.optinfo)
if [ "$CCNAME" = "gcc" ] && [ "$CCVERSION" -ge 9 ]; then
GZME="$GZME ${x##*=}"
set -- "$@" "$x"
fi
;;
-R*) # e.g. clang's -Rpass-missed=all
if [ "${PLAT#*clang}" != "${PLAT}" ]; then
set -- "$@" "$x"
fi
;;
-fsave-optimization-record) # clang only
if [ "${PLAT#*clang}" != "${PLAT}" ]; then
set -- "$@" "$x"
fi
;;
*)
set -- "$@" "$x"
;;
esac
done
if [ -z "$FDIAGNOSTIC_COLOR" ] && [ "$TERM" != "dumb" ]; then
FDIAGNOSTIC_COLOR=-fdiagnostics-color=always
fi
if [ "${PLAT#*clang}" != "${PLAT}" ]; then
FIRST=1
for x; do
# clang's assembler isn't complete yet
if [ $FIRST -eq 1 ]; then
set -- \
"$x" \
-fno-integrated-as \
-Wno-unused-command-line-argument \
-Wno-incompatible-pointer-types-discards-qualifiers
FIRST=0
continue
fi
TRAPV= # clang handles -f{,no-}{trap,wrap}v weird
# removes flags clang whines about
case "$x" in
-gstabs) ;;
-ftrapv) ;;
-ffixed-*) ;;
-fcall-saved*) ;;
-fsignaling-nans) ;;
-fcx-limited-range) ;;
-fno-fp-int-builtin-inexact) ;;
-Wno-unused-but-set-variable) ;;
-Wunsafe-loop-optimizations) ;;
-mdispatch-scheduler) ;;
-ftracer) ;;
-frounding-math) ;;
-fmerge-constants) ;;
-fmodulo-sched) ;;
-msse2avx)
set -- "$@" -Wa,-msse2avx
;;
-fopt-info-vec) ;;
-fopt-info-vec-missed) ;;
-fmodulo-sched-allow-regmoves) ;;
-fgcse-*) ;;
-freschedule-modulo-scheduled-loops) ;;
-freschedule-modulo-scheduled-loops) ;;
-fipa-pta) ;;
-fsched2-use-superblocks) ;;
-fbranch-target-load-optimize) ;;
-fdelete-dead-exceptions) ;;
-funsafe-loop-optimizations) ;;
-fcall-used*) ;;
-mmitigate-rop) ;;
-mnop-mcount) ;;
-fno-align-jumps) ;;
-fno-align-labels) ;;
-fno-align-loops) ;;
-fivopts) ;;
-fschedule-insns) ;;
-fno-semantic-interposition) ;;
-mno-fentry) ;;
-f*shrink-wrap) ;;
-f*schedule-insns2) ;;
-fvect-cost-model=*) ;;
-fsimd-cost-model=*) ;;
-fversion-loops-for-strides) ;;
-fopt-info*) ;;
-f*var-tracking-assignments) ;;
-femit-struct-debug-baseonly) ;;
-ftree-loop-vectorize) ;;
-gdescribe-dies) ;;
-flimit-function-alignment) ;;
-ftree-loop-im) ;;
-fno-instrument-functions) ;;
-fstack-clash-protection) ;;
-mstringop-strategy=*) ;;
-mpreferred-stack-boundary=*) ;;
-*stack-protector*) ;; # clang requires segmented memory for this
-f*gnu-unique) ;;
-Wframe-larger-than=*) ;;
-f*whole-program) ;;
-Wa,--size-check=*) ;;
-Wa,--listing*) ;;
-mfpmath=sse+387) ;;
-Wa,--noexecstack) ;;
-freg-struct-return) ;;
-mcall-ms2sysv-xlogues) ;;
-mno-vzeroupper)
set -- "$@" -mllvm -x86-use-vzeroupper=0
;;
-Wa,-a*)
x="${x#*=}"
if [ "$x" ] && [ -p "$x" ]; then
printf '' >"$x"
fi
;;
*)
set -- "$@" "$x"
;;
esac
done
set -- "$@" -fno-stack-protector
else
# removes flags only clang supports
FIRST=1
for x; do
if [ $FIRST -eq 1 ]; then
set --
FIRST=0
fi
case "$x" in
-Oz) set -- "$@" -Os ;;
*) set -- "$@" "$x" ;;
esac
done
fi
set -- "$@" -no-canonical-prefixes $FDIAGNOSTIC_COLOR $COUNTERMAND
if [ "$SILENT" = "0" ]; then
printf "%s\n" "$*" >&2
else
printf "$LOGFMT" "${ACTION:-COMPILE}" "${TARGET:-$OUT}" >&2
fi
OUTDIR="${OUT%/*}"
if [ "$OUTDIR" != "$OUT" ] && [ ! -d "$OUTDIR" ]; then
$MKDIR "$OUTDIR" || exit 2
fi
REASON=failed
trap REASON=interrupted INT
if "$@"; then
for f in $GZME; do
if GZ=${GZ:-$(command -v gzip)}; then
if [ -f "$f" ]; then
build/actuallynice $GZ $ZFLAGS -qf $f &
fi
fi
done
exit 0
fi
if [ "$TERM" = "dumb" ]; then
f='%s %s\r\n\r\n'
else
f='\033[91m%s\033[39m \033[94m%s\033[39m\r\n\r\n'
fi
printf "$f" "$CCNAME $CCVERSION: compile $REASON:" "$*" >&2
exit 1