qbe/Makefile
Roland Paterson-Jones c2ff93e75e Global Value Numbering / Global Code Motion
More or less as proposed in its ninth iteration with the
addition of a gcmmove() functionality to restore coherent
local schedules.

Changes since RFC 8:

Features:

 - generalization of phi 1/0 detection
 - collapse linear jmp chains before GVN; simplifies if-graph
     detection used in 0/non-0 value inference and if-elim...
 - infer 0/non-0 values from dominating blk jnz; eliminates
     redundant cmp eq/ne 0 and associated jnz/blocks, for example
     redundant null pointer checks (hare codebase likes this)
 - remove (emergent) empty if-then-else graphlets between GVN and
     GCM; improves GCM instruction placement, particularly cmps.
 - merge %addr =l add %addr1, N sequences - reduces tmp count,
     register pressure.
 - squash consecutive associative ops with constant args, e.g.
     t1 = add t, N ... t2 = add t2, M -> t2 = add t, N+M

Bug Fixes:

 - remove "cmp eq/ne of non-identical RCon's " in copyref().
   RCon's are not guaranteed to be dedup'ed, and symbols can
   alias.

Codebase:

  - moved some stuff into cfg.c including blkmerge()
  - some refactoring in gvn.c
  - simplification of reassoc.c - always reassoc all cmp ops
      and Kl add %t, N. Better on coremark, smaller codebase.
  - minor simplification of movins() - use vins

Testing - standard QBE, cproc, hare, harec, coremark
          [still have Rust build issues with latest roland]

Benchmark
- coremark is ~15%+ faster than master
- hare "HARETEST_INCLUDE='slow' make check" ~8% faster
    (crypto::sha1::sha1_1gb is biggest obvious win - ~25% faster)

Changes since RFC 7:

Bug fixes:

- remove isbad4gcm() in GVN/GCM - it is unsound due to different state
    at GVN vs GCM time; replace with "reassociation" pass after GCM
- fix intra-blk use-before-def after GCM
- prevent GVN from deduping trapping instructions cos GCM will not
    move them
- remove cmp eq/ne identical arg copy detection for floating point, it
    is not valid for NaN
- fix cges/cged flagged as commutative in ops.h instead of cnes/cned
    respectively; just a typo

Minor features:

- copy detection handles cmp le/lt/ge/gt with identical args
- treat (integer) div/rem by non-zero constant as non-trapping
- eliminate add N/sub N pairs in copy detection
- maintain accurate tmp use in GVN; not strictly necessary but enables
    interim global state sanity checking
- "reassociation" of trivial constant offset load/store addresses, and
    cmp ops with point-of-use in pass after GCM
- normalise commutative op arg order - e.g. op con, tmp -> op tmp, con
    to simplify copy detection and GVN instruction dedup

Codebase:

- split out core copy detection and constant folding (back) out into
    copy.c, fold.c respectively; gvn.c was getting monolithic
- generic support for instruction moving in ins.c - used by GCM and
    reassoc
- new reassociation pass in reassoc.c
- other minor clean-up/refactor

Changes since RFC 6:

- More ext elimination in GVN by examination of def and use bit width
- elimination of redundant and mask by bit width examination
- Incorporation of Song's patch

Changes since RFC 5:

- avoidance of "bad" candidates for GVN/GCM - trivial address offset
    calculations, and comparisons
- more copy detection mostly around boolean values
- allow elimination of unused load, alloc, trapping instructions
- detection of trivial boolean v ? 1 : 0 phi patterns
- bug fix for (removal of) "chg" optimisation in ins recreation - it
    was missing removal of unused instructions in some cases

ifelim() between GVN and GCM; deeper nopunused()
2025-03-14 09:58:37 +01:00

98 lines
2.5 KiB
Makefile

.POSIX:
.SUFFIXES: .o .c
PREFIX = /usr/local
BINDIR = $(PREFIX)/bin
COMMOBJ = main.o util.o parse.o abi.o cfg.o mem.o ssa.o alias.o load.o \
copy.o fold.o gvn.o gcm.o ins.o simpl.o live.o \
spill.o rega.o emit.o
AMD64OBJ = amd64/targ.o amd64/sysv.o amd64/isel.o amd64/emit.o
ARM64OBJ = arm64/targ.o arm64/abi.o arm64/isel.o arm64/emit.o
RV64OBJ = rv64/targ.o rv64/abi.o rv64/isel.o rv64/emit.o
OBJ = $(COMMOBJ) $(AMD64OBJ) $(ARM64OBJ) $(RV64OBJ)
SRCALL = $(OBJ:.o=.c)
CC = cc
CFLAGS = -std=c99 -g -Wall -Wextra -Wpedantic
qbe: $(OBJ)
$(CC) $(LDFLAGS) $(OBJ) -o $@
.c.o:
$(CC) $(CFLAGS) -c $< -o $@
$(OBJ): all.h ops.h
$(AMD64OBJ): amd64/all.h
$(ARM64OBJ): arm64/all.h
$(RV64OBJ): rv64/all.h
main.o: config.h
config.h:
@case `uname` in \
*Darwin*) \
case `uname -m` in \
*arm64*) \
echo "#define Deftgt T_arm64_apple";\
;; \
*) \
echo "#define Deftgt T_amd64_apple";\
;; \
esac \
;; \
*) \
case `uname -m` in \
*aarch64*|*arm64*) \
echo "#define Deftgt T_arm64"; \
;; \
*riscv64*) \
echo "#define Deftgt T_rv64"; \
;; \
*) \
echo "#define Deftgt T_amd64_sysv";\
;; \
esac \
;; \
esac > $@
install: qbe
mkdir -p "$(DESTDIR)$(BINDIR)"
install -m755 qbe "$(DESTDIR)$(BINDIR)/qbe"
uninstall:
rm -f "$(DESTDIR)$(BINDIR)/qbe"
clean:
rm -f *.o */*.o qbe
clean-gen: clean
rm -f config.h
check: qbe
tools/test.sh all
check-arm64: qbe
TARGET=arm64 tools/test.sh all
check-rv64: qbe
TARGET=rv64 tools/test.sh all
src:
@echo $(SRCALL)
80:
@for F in $(SRCALL); \
do \
awk "{ \
gsub(/\\t/, \" \"); \
if (length(\$$0) > $@) \
printf(\"$$F:%d: %s\\n\", NR, \$$0); \
}" < $$F; \
done
wc:
@wc -l $(SRCALL)
.PHONY: clean clean-gen check check-arm64 check-rv64 src 80 wc install uninstall