MIPS64: Fix hidden bug in relocations for j and jal.

MIPS64: Fix hidden bug in relocations for j and jal.

Introduce new mechanism for relocating j/jal.

Resolves flaky failures of mozilla regress tests.

Additionally:

- internal encoded references are not relocated during code generation phase.
- remove asserts from j and jal which are not
valid because addresses are not final and valid in code generation phase.


TEST=mozilla/js1_5/Regress/regress-280769-2, regress-367561-01,
     mozilla/ecma_3/Statements/regress-444979
BUG=

[dusmil.imgtec, 2015-06-30 13:49:19]

dusan.milosavljevic@imgtec.com changed reviewers:
+ akos.palfi@imgtec.com, balazs.kilvady@imgtec.com, djordje.pesic@imgtec.com,
ilija.pavlovic@imgtec.com, paul.lind@imgtec.com

[dusmil.imgtec, 2015-06-30 17:09:12]

Hmm, I am not satisfied with solution.
What if address for linked variable is at start of 256MB during code generation
so this is encoded as zero in j(),
and this can  misinterpreted as endOfJumpChain.

[paul.l..., 2015-07-01 03:35:29]

Right, you mean the temporary assembly buffer just happens to cross 256MB
boundary. There is no restriction from that, I agree.

As a nit: I am having trouble with the name 'IsAllAddressValid' - its not clear
what exactly that means, and it gets more confusing when passing true/false and
then using inverse conditions: if (!IsAllAddressValid && ...). I don't have a
better name suggestion right now, but this might be a place where it is worth
creating enum names, and not pass around true/false - just for readability.

[dusmil.imgtec, 2015-07-23 10:26:18]

PTAL.

[paul.l..., 2015-08-01 17:02:22]

Nice fix! LGTM, modulo the two typos. I will fix these and land this now.

https://codereview.chromium.org/1216823003/diff/60001/src/mips64/assembler-mi...
File src/mips64/assembler-mips64.cc (right):

https://codereview.chromium.org/1216823003/diff/60001/src/mips64/assembler-mi...
src/mips64/assembler-mips64.cc:1455: j(imm);
typo: this should be jal()

https://codereview.chromium.org/1216823003/diff/60001/src/mips64/macro-assemb...
File src/mips64/macro-assembler-mips64.cc (right):

https://codereview.chromium.org/1216823003/diff/60001/src/mips64/macro-assemb...
src/mips64/macro-assembler-mips64.cc:2758: J(L, bdslot);
This should be Jal(L, bdslot), was incorrect from 962703cac
(https://codereview.chromium.org/1147503002)

[paul.l..., 2015-08-01 17:10:07]

Committed manually as https://crrev.com/38501327599ae6ac7c255205c61c00aeed09da13