MIPS: Debugger: use debug break slots to break at function exit.

MIPS: Debugger: use debug break slots to break at function exit.

By not having to patch the return sequence (we patch the debug
break slot right before it), we don't overwrite it and therefore
don't have to keep the original copy of the code around.

BUG=v8:4269
LOG=N

[paul.l..., 2015-07-14 19:15:59]

paul.lind@imgtec.com changed reviewers:
+ paul.lind@imgtec.com

[paul.l..., 2015-07-14 19:15:59]

code l-g-t-m, some nits in the comments :-)

https://codereview.chromium.org/1233213002/diff/1/src/mips/assembler-mips-inl.h
File src/mips/assembler-mips-inl.h (right):

https://codereview.chromium.org/1233213002/diff/1/src/mips/assembler-mips-inl...
src/mips/assembler-mips-inl.h:369: // debug-mips.cc
BreakLocation::SetDebugBreakAtReturn(), or
comment nit: remove mention of deleted function
BreakLocation::SetDebugBreakAtReturn()

https://codereview.chromium.org/1233213002/diff/1/src/mips/debug-mips.cc
File src/mips/debug-mips.cc (right):

https://codereview.chromium.org/1233213002/diff/1/src/mips/debug-mips.cc#newc...
src/mips/debug-mips.cc:34: // the constant pool in the debug break slot code.
nit: constant pool -> trampoline pool

https://codereview.chromium.org/1233213002/diff/1/src/mips64/assembler-mips64...
File src/mips64/assembler-mips64-inl.h (right):

https://codereview.chromium.org/1233213002/diff/1/src/mips64/assembler-mips64...
src/mips64/assembler-mips64-inl.h:360: // debug break slot per
BreakLocation::SetDebugBreakAtSlot().
comment nit: remove ref to removed function SetDebugBreakAtReturn()

https://codereview.chromium.org/1233213002/diff/1/src/mips64/debug-mips64.cc
File src/mips64/debug-mips64.cc (right):

https://codereview.chromium.org/1233213002/diff/1/src/mips64/debug-mips64.cc#...
src/mips64/debug-mips64.cc:33: // the constant pool in the debug break slot
code.
comment nit: 'constant' -> trampoline

[balazs.kilvady, 2015-07-14 19:30:22]

https://codereview.chromium.org/1233213002/diff/1/src/mips/assembler-mips-inl.h
File src/mips/assembler-mips-inl.h (right):

https://codereview.chromium.org/1233213002/diff/1/src/mips/assembler-mips-inl...
src/mips/assembler-mips-inl.h:369: // debug-mips.cc
BreakLocation::SetDebugBreakAtReturn(), or
On 2015/07/14 19:15:59, paul.l... wrote:
> comment nit: remove mention of deleted function
> BreakLocation::SetDebugBreakAtReturn()

Done.

https://codereview.chromium.org/1233213002/diff/1/src/mips/debug-mips.cc
File src/mips/debug-mips.cc (right):

https://codereview.chromium.org/1233213002/diff/1/src/mips/debug-mips.cc#newc...
src/mips/debug-mips.cc:34: // the constant pool in the debug break slot code.
On 2015/07/14 19:15:59, paul.l... wrote:
> nit: constant pool -> trampoline pool

Done.

https://codereview.chromium.org/1233213002/diff/1/src/mips64/assembler-mips64...
File src/mips64/assembler-mips64-inl.h (right):

https://codereview.chromium.org/1233213002/diff/1/src/mips64/assembler-mips64...
src/mips64/assembler-mips64-inl.h:360: // debug break slot per
BreakLocation::SetDebugBreakAtSlot().
On 2015/07/14 19:15:59, paul.l... wrote:
> comment nit: remove ref to removed function SetDebugBreakAtReturn()

Done.

https://codereview.chromium.org/1233213002/diff/1/src/mips64/debug-mips64.cc
File src/mips64/debug-mips64.cc (right):

https://codereview.chromium.org/1233213002/diff/1/src/mips64/debug-mips64.cc#...
src/mips64/debug-mips64.cc:33: // the constant pool in the debug break slot
code.
On 2015/07/14 19:15:59, paul.l... wrote:
> comment nit: 'constant' -> trampoline

Done.

[paul.l..., 2015-07-14 19:48:34]

l-g-t-m for merge into https://codereview.chromium.org/1234833003/