Austin Clements a8ae93fd26 runtime: fix heap bitmap repeating with large scalar tails ... When heapBitsSetType repeats a source bitmap with a scalar tail (typ.ptrdata < typ.size), it lays out the tail upon reaching the end of the source bitmap by simply increasing the number of bits claimed to be in the incoming bit buffer. This causes later iterations to read the appropriate number of zeros out of the bit buffer before starting on the next repeat of the source bitmap. Currently, however, later iterations of the loop continue to read bits from the source bitmap *regardless of the number of bits currently in the bit buffer*. The bit buffer can only hold 32 or 64 bits, so if the scalar tail is large and the padding bits exceed the size of the bit buffer, the read from the source bitmap on the next iteration will shift the incoming bits into oblivion when it attempts to put them in the bit buffer. When the buffer does eventually shift down to where these bits were supposed to be, it will contain zeros. As a result, words that should be marked as pointers on later repetitions are marked as scalars, so the garbage collector does not trace them. If this is the only reference to an object, it will be incorrectly freed. Fix this by adding logic to drain the bit buffer down if it is large instead of reading more bits from the source bitmap. Fixes #11286. Change-Id: I964432c4b9f1cec334fc8c3da0ff16460203feb6 Reviewed-on: https://go-review.googlesource.com/11360 Reviewed-by: Russ Cox <rsc@golang.org>		2015-06-23 18:37:17 +00:00
..
bench	all: retire architecture letter in file names, public API	2015-05-21 17:32:17 +00:00
bugs	test: migrate remaining tests to run.go	2014-12-22 22:41:34 +00:00
chan	cmd/gc: implement 'for range x {'	2014-07-16 19:27:10 -04:00
ddd2.dir	…
dwarf	…
fixedbugs	runtime: fix heap bitmap repeating with large scalar tails	2015-06-23 18:37:17 +00:00
import2.dir	…
import4.dir	test: match gccgo import error messages	2013-12-12 19:02:11 -08:00
interface	cmd/internal/gc: improve "type *X has no field or method M" message	2015-05-07 16:21:57 +00:00
ken	…
method4.dir	cmd/gc: do not omit wrapper for expression (interface{...}).F	2014-01-07 13:26:48 +01:00
safe	…
stress	build: adjustments for move from src/pkg to src	2014-09-08 00:06:45 -04:00
syntax	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
64bit.go	…
235.go	…
alias.go	…
alias1.go	…
append.go	…
args.go	…
assign.go	cmd/gc: prohibit short variable declarations containing duplicate symbols	2014-10-06 17:16:39 -04:00
assign1.go	…
bigalg.go	…
bigmap.go	…
blank.go	test: revert changes made for Go SSA interpreter test.	2013-10-08 14:36:20 -04:00
blank1.go	test: match gccgo error messages for blank1.go	2013-09-28 15:19:05 -07:00
bom.go	…
bombad.go	…
bounds.go	…
chancap.go	…
chanlinear.go	runtime: test for linear enqueue/dequeue behavior	2014-12-08 22:18:17 +00:00
char_lit.go	…
char_lit1.go	…
clearfat.go	[dev.power64] 9g: fix under-zeroing in clearfat	2014-10-31 11:08:27 -04:00
closedchan.go	…
closure.go	…
closure1.go	cmd/gc: capture variables by value	2015-01-29 13:07:30 +00:00
closure2.go	cmd/gc: fix capturing by value for range statements	2015-02-03 15:48:48 +00:00
cmp.go	cmd/gc: do not nop-convert equivalent but different interface types.	2014-02-27 08:07:50 +01:00
cmp6.go	cmd/gc: do not consider length zero arrays as comparable.	2014-01-31 00:30:56 +01:00
cmplx.go	cmd/gc: reject complex calls with mismatched argument types.	2013-03-11 22:55:14 +01:00
cmplxdivide.c	test: comment the behavior and use of cmplxdivide*	2015-01-15 00:00:06 +00:00
cmplxdivide.go	test: comment the behavior and use of cmplxdivide*	2015-01-15 00:00:06 +00:00
cmplxdivide1.go	…
complit.go	…
complit1.go	cmd/internal/gc: accept map literals with omitted key type	2015-06-04 02:31:38 +00:00
compos.go	…
const.go	…
const1.go	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
const2.go	…
const3.go	…
const4.go	…
const5.go	cmd/gc: reject builtin function calls in len(fixed array) constants	2014-04-03 19:04:33 -04:00
const6.go	test: match gccgo error strings.	2013-06-26 18:05:02 +02:00
convT2X.go	…
convert.go	…
convert1.go	…
convert3.go	…
convlit.go	cmd/internal/gc: unsafe.Pointer constants may only be converted to uintptr	2015-05-07 23:54:28 +00:00
convlit1.go	…
copy.go	…
crlf.go	…
ddd.go	…
ddd1.go	…
ddd2.go	…
decl.go	…
declbad.go	…
defer.go	…
deferfin.go	runtime: combine small NoScan allocations	2014-01-24 22:35:11 +04:00
deferprint.go	…
deferprint.out	…
divide.go	…
divmod.go	all: fix a few spelling errors in source comments	2013-12-27 08:59:02 -08:00
empty.go	…
env.go	…
eof.go	…
eof1.go	…
errchk	test/errchk: use "#!/usr/bin/env perl" shebang line	2013-05-23 04:41:22 +08:00
escape.go	…
escape2.go	cmd/compile: move Node.Curfn into both Node.Func and Node.Name	2015-06-03 20:09:52 +00:00
escape2n.go	cmd/compile: move Node.Curfn into both Node.Func and Node.Name	2015-06-03 20:09:52 +00:00
escape3.go	…
escape4.go	cmd/internal/gc: transitive inlining	2015-02-26 17:36:00 +00:00
escape5.go	cmd/internal/gc: move check for large-hence-heap-allocated types into escape analysis	2015-05-22 02:13:54 +00:00
escape_array.go	cmd/internal/gc: move check for large-hence-heap-allocated types into escape analysis	2015-05-22 02:13:54 +00:00
escape_calls.go	cmd/internal/gc: make indirect calls properly escape-y	2015-05-22 01:36:11 +00:00
escape_closure.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_field.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_iface.go	test: add tests for escape analysis of interface conversions	2015-03-28 16:15:27 +00:00
escape_indir.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_level.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_map.go	test: add tests for escape analysis of interface conversions	2015-03-28 16:15:27 +00:00
escape_param.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_slice.go	cmd/internal/gc: extend escape analysis to pointers in slices	2015-05-18 15:34:39 +00:00
escape_struct_param1.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_struct_param2.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
escape_struct_return.go	cmd/internal/gc: improve flow of input params to output params	2015-05-01 13:47:20 +00:00
fibo.go	Fix whitespace (use blanks consistently).	2014-12-08 22:22:58 +00:00
float_lit.go	…
float_lit2.go	test: fix two typos in float_lit2.go	2014-05-21 17:19:12 -04:00
float_lit3.go	test/float_lit2.go: rewrite to test values near boundaries	2014-05-21 17:12:06 -04:00
floatcmp.go	…
for.go	…
func.go	…
func1.go	cmd/gc: ensure unique parameter and result names in function types	2013-03-15 15:24:13 -04:00
func2.go	…
func3.go	…
func4.go	…
func5.go	…
func6.go	…
func7.go	…
func8.go	…
funcdup.go	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
funcdup2.go	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
gc.go	…
gc1.go	…
gc2.go	test: check for build constraints only upto the first blank line	2015-02-06 05:36:26 +00:00
gcstring.go	runtime: fix empty string handling in garbage collector	2014-03-11 23:58:39 -04:00
goprint.go	test: make goprint.go wait longer for go its routine to execute	2013-04-12 16:04:19 -07:00
goprint.out	…
goto.go	Revert "cmd/internal/gc: ignore declarations of types for goto validation"	2015-05-15 16:35:49 +00:00
helloworld.go	…
helloworld.out	…
if.go	…
import.go	…
import1.go	test: match gccgo import error messages	2013-12-12 19:02:11 -08:00
import2.go	…
import4.go	…
import5.go	…
index.go	test: recognize gccgo error message in index.go	2013-09-27 20:38:52 -07:00
index0.go	…
index1.go	…
index2.go	…
indirect.go	…
indirect1.go	…
init.go	…
init1.go	test: deflake init1.go test, tighten its bounds	2015-02-13 22:13:56 +00:00
initcomma.go	…
initialize.go	…
initializerr.go	…
inline.go	cmd/internal/gc: transitive inlining	2015-02-26 17:36:00 +00:00
int_lit.go	…
intcvt.go	…
iota.go	…
label.go	…
label1.go	…
linkx.go	cmd/link: deprecate -X name value in favor of -X name=value	2015-06-05 04:55:41 +00:00
linkx_run.go	cmd/link: deprecate -X name value in favor of -X name=value	2015-06-05 04:55:41 +00:00
literal.go	…
live.go	test: add -update_errors flag to run script	2015-04-10 11:33:42 +00:00
live1.go	cmd/gc: correct liveness for fat variables	2014-02-15 10:58:55 -05:00
live2.go	cmd/gc: allocate non-escaping maps on stack	2015-02-12 09:53:52 +00:00
mallocfin.go	…
map.go	test/mapnan.go: add regression test for non-empty interfaces.	2014-08-06 17:02:55 -04:00
map1.go	…
maplinear.go	test: make maplinear more robust	2014-10-27 18:59:02 -04:00
method.go	…
method1.go	…
method2.go	cmd/gc: fix method values whose receiver is an unnamed interface.	2013-08-29 10:00:58 +02:00
method3.go	…
method4.go	…
method5.go	cmd/gc: implement method values	2013-03-20 17:11:09 -04:00
named.go	…
named1.go	cmd/gc: comma-ok assignments produce untyped bool as 2nd result	2014-08-11 16:11:55 -07:00
nil.go	…
nilcheck.go	cmd/gc: optimize existence-only map lookups	2015-01-07 22:36:06 +00:00
nilptr.go	test/nilptr: add more tests	2013-09-05 23:06:34 -04:00
nilptr2.go	test: revert changes made for Go SSA interpreter test.	2013-10-08 14:36:20 -04:00
nilptr3.go	cmd/7g: enable peephole optimizer	2015-04-08 08:16:54 +00:00
nilptr4.go	cmd/gc: fix bad checknil with ints on 32 bit compilers	2014-02-26 12:25:13 -08:00
nosplit.go	test: fix build on GOARCH=ppc64/ppc64le	2015-06-06 20:22:57 +00:00
nul1.go	…
parentype.go	…
peano.go	…
print.go	runtime: move built-in print routines to go.	2014-07-31 13:48:48 -07:00
print.out	runtime: move built-in print routines to go.	2014-07-31 13:48:48 -07:00
printbig.go	…
printbig.out	…
range.go	cmd/gc: implement 'for range x {'	2014-07-16 19:27:10 -04:00
recover.go	test: add more cases to recover.go	2014-10-22 08:06:15 -07:00
recover1.go	…
recover2.go	…
recover3.go	tests: remove two misuses of nil pointers	2013-08-15 11:51:04 -04:00
recover4.go	test: fix recover4 test on 64kb systems	2015-03-17 05:25:01 +00:00
rename.go	…
rename1.go	…
reorder.go	…
reorder2.go	cmd/gc: shorten temporary lifetimes when possible	2014-04-01 13:31:38 -04:00
return.go	test: add cases to return.go that gccgo got wrong	2013-08-07 11:31:01 -07:00
rotate.go	…
rotate0.go	test: re-enable rotate tests	2015-05-28 19:40:58 +00:00
rotate1.go	test: re-enable rotate tests	2015-05-28 19:40:58 +00:00
rotate2.go	test: re-enable rotate tests	2015-05-28 19:40:58 +00:00
rotate3.go	test: re-enable rotate tests	2015-05-28 19:40:58 +00:00
run.go	cmd/compile: run escape analysis after method wrapper generation	2015-06-17 02:36:45 +00:00
rune.go	…
runtime.go	…
shift1.go	test: avoid "declared but not used" errors in shift1.go	2014-07-20 12:25:24 -07:00
shift2.go	test: add shift expression incorrectly rejected by gccgo.	2013-06-25 08:06:34 +02:00
sieve.go	…
sigchld.go	test: skip SIGCHLD test on Plan 9	2014-01-29 09:28:23 +01:00
sigchld.out	…
simassign.go	…
sinit.go	test: move linkx and sinit to run.go	2014-11-06 15:14:08 -05:00
sinit_run.go	all: retire architecture letter in file names, public API	2015-05-21 17:32:17 +00:00
sizeof.go	test: correct sizeof.go.	2013-06-02 19:10:11 +02:00
slice3.go	cmd/gc, runtime: treat slices and strings like pointers in garbage collection	2014-08-25 14:38:19 -04:00
slice3err.go	test: match gccgo error messages	2013-12-12 17:18:12 -08:00
slicecap.go	cmd/gc, runtime: treat slices and strings like pointers in garbage collection	2014-08-25 14:38:19 -04:00
sliceopt.go	cmd/internal/gc: optimize slice + write barrier	2015-05-13 19:20:39 +00:00
solitaire.go	…
stack.go	…
string_lit.go	test: add []rune case to string_lit.go	2013-12-12 17:17:02 -08:00
stringrange.go	…
struct0.go	…
switch.go	cmd/gc: disallow fallthrough in final case of switch	2013-03-15 00:35:09 -04:00
switch3.go	…
switch4.go	cmd/gc: disallow fallthrough in final case of switch	2013-03-15 00:35:09 -04:00
tinyfin.go	runtime: combine small NoScan allocations	2014-01-24 22:35:11 +04:00
torture.go	cmd/8g: don't allocate a register early for cap(CHAN).	2014-07-01 09:20:51 +02:00
turing.go	…
typecheck.go	cmd/gc: silence assignment errors to undefined symbols	2014-01-03 21:03:20 +01:00
typeswitch.go	…
typeswitch1.go	…
typeswitch2.go	…
typeswitch3.go	…
undef.go	…
utf.go	…
varerr.go	…
varinit.go	…
writebarrier.go	cmd/internal/gc: add missing write barrier in append(x, BigStructWithPointers)	2015-05-19 15:28:29 +00:00
zerodivide.go	…