remove "regexp." from regexp tests.

R=rsc
DELTA=1173  (1152 added, 1 deleted, 20 changed)
OCL=33028
CL=33037

R=rsc
DELTA=16  (12 added, 0 deleted, 4 changed)
OCL=33030
CL=33035

R=rsc
DELTA=80  (40 added, 40 deleted, 0 changed)
OCL=33024
CL=33027

R=r
DELTA=95  (0 added, 0 deleted, 95 changed)
OCL=33012
CL=33012

x.go:3: invalid indirect of X (type int)

was
x.go:3: invalid indirect of nil

R=ken
OCL=33008
CL=33008

- runs approx. 30% faster

R=r
DELTA=24  (10 added, 2 deleted, 12 changed)
OCL=32984
CL=33005

- wrote corresponding fast versions in fast.arith.s
- implemented in-place operations for some routines
- updated existing code to be compatible with in-place
  routines

These changes allow the pidigits benchmark to run
approx. 30% faster. Enabling the assembly routines
in fast.arith.s will give another approx. 3%.

R=r
DELTA=486  (252 added, 68 deleted, 166 changed)
OCL=32980
CL=33003

R=rsc
DELTA=90  (90 added, 0 deleted, 0 changed)
OCL=32993
CL=33001

non-addressable expressions.

R=rsc
APPROVED=rsc
DELTA=241  (202 added, 15 deleted, 24 changed)
OCL=32790
CL=32995

R=ken
OCL=32975
CL=32975

R=rsc
OCL=32971
CL=32971

AllMatchesStringIter, based on sawn and sawzall functions in sawzall.

APPROVED=rsc
DELTA=218  (218 added, 0 deleted, 0 changed)
OCL=32408
CL=32949

APPROVED=rsc
DELTA=1  (1 added, 0 deleted, 0 changed)
OCL=32948
CL=32948

R=rsc
OCL=32947
CL=32947

2. moved functions from 6g to gc
for portability to other families.
3. added rotate-carry instructions to
peek and reg.

R=rsc
OCL=32946
CL=32946

Fix octal parsing that it unearthed.

R=rsc
APPROVED=rsc
DELTA=11  (5 added, 0 deleted, 6 changed)
OCL=32924
CL=32945

R=rsc
DELTA=293  (224 added, 0 deleted, 69 changed)
OCL=32917
CL=32944

only need to fix up certain
denominators

R=rsc
OCL=32928
CL=32928

still to do - overflow, mod

R=rsc
OCL=32927
CL=32927

no real change -- disabled because of bugs

R=rsc
OCL=32923
CL=32923

- added some TODOs

DELTA=46  (15 added, 4 deleted, 27 changed)
OCL=32901
CL=32918

R=ken
OCL=32902
CL=32914

R=rsc
DELTA=514  (513 added, 0 deleted, 1 changed)
OCL=32898
CL=32910

hope this will work around Mac NFS bug
where writing to an 8.out that has crashed
recently sometimes wedges NFS.

R=r
DELTA=3  (3 added, 0 deleted, 0 changed)
OCL=32906
CL=32908

R=ken
OCL=32900
CL=32900

TBR=r
OCL=32896
CL=32896

R=ken
OCL=32890
CL=32894

R=rsc
DELTA=7  (3 added, 3 deleted, 1 changed)
OCL=32885
CL=32889

R=ken
OCL=32888
CL=32888

R=ken
OCL=32887
CL=32887

R=ken
OCL=32886
CL=32886

disable func redeclaration mismatch test;
fix golden.out

R=ken
OCL=32883
CL=32883

R=ken
OCL=32882
CL=32882

more interesting than most

R=rsc
DELTA=132  (131 added, 0 deleted, 1 changed)
OCL=32876
CL=32881

still to do:
	* initializer cycle detection
	* nicer error for type checking cycles

R=ken
OCL=32855
CL=32880

R=rsc
DELTA=25  (23 added, 0 deleted, 2 changed)
OCL=32873
CL=32875

R=rsc
OCL=32858
CL=32858

TBR=rsc
OCL=32857
CL=32857

- extra bignum.go functionality for pidigits.go
- tuned bignum multiplication

R=r
DELTA=193  (186 added, 0 deleted, 7 changed)
OCL=32852
CL=32856

R=rsc
DELTA=1276  (1275 added, 0 deleted, 1 changed)
OCL=32851
CL=32854