This allows 'move {CONST, $1}, R3' with a small enough $1 to emit one
instruction (addi) instead of two instructions (addis, ori). The
CONST token confusingly isn't in the CONST_ALL set.
The spec says, "ASS w: Adjust the stack pointer by w-byte integer".
The w argument "can either be given as argument or on top of the
stack." Therefore, 'ass 4' would pop the 4-byte integer from the
stack, but 'ass' would pop the size w from the stack, then pop the
w-byte integer.
PowerPC ncg wrongly implemented 'ass' as if it was 'ass 4'. Fix it to
accept only 'ass 4'.
These instructions would load or store the EM heap pointer. They
don't work. Programs must use brk() or sbrk() in libsys.
The last file to use 'lor 2' and 'str 2' was lang/pc/libpc/sav.e in
the Pascal library. Commit c084f9f deleted the file, so we no longer
need rules 'lor 2' or 'str 2' to build the ACK.
corresponding invocation in the ncg table so the same helpers can be used for
both mcg and ncg. Add a new IR opcode, FARJUMP, which jumps to a helper
function but saves volatile registers.
register 'type'; now use int/float/long/double throughout to identify
registers. Lots of register allocator tweaks and table bugfixes --- we now get
through the dreading Mathlib.mod!
This would have happened later, if f14 to f31 became regvar (like r13
to r31 are now). I am doing it now because ncg is too slow for rules
"with FREG FREG uses FREG". We use such rules for adf 8 and other EM
instructions that operate on 2 floats. Like my last commit cfbc537,
this commit speeds ncg by removing choices for register allocation.
ncg is too slow with this many registers. A stack pattern "with GPR
GPR GPR" or "with REG REG REG" takes too long to pick registers,
causing ncg 8 to take about 2 seconds on each sti 8. I introduce
REG_PAIR and there are only 4 such pairs.
For programs that use sti 8 (including C programs that copy 8-byte
structs), this speed hack improves the ncg run from several seconds to
almost instantaneous.
Also add a few COMMENT(...) lines in stacking rules.
This fixes the SIGILL (illegal instruction) in startrek when firing
phasers. The 32-bit processors in my PowerPC Mac and in QEMU don't
have fctid, a 64-bit instruction.
I got the idea from mach/proto/fp/fif8.c to extract the exponent,
clear some bits to get an integer, then subtract the integer from
the original value to get the fraction.