This also fixes bugs found by the new test. It only tests stepping
inside of wasm code. Wasm to JS and vice versa will follow in another
CL.

R=yangguo@chromium.org, titzer@chromium.org, kozyatinskiy@chromium.org
BUG=v8:5822

Review-Url: https://codereview.chromium.org/2651043004
Cr-Commit-Position: refs/heads/master@{#42729}

This action was used by inspector for blackboxing and isn't needed with new blackboxing implementation inside V8.

BUG=none
R=yangguo@chromium.org,clemensh@chromium.org
TBR=bmeurer@chromium.org

Review-Url: https://codereview.chromium.org/2650943011
Cr-Commit-Position: refs/heads/master@{#42670}

Implement stepping by remembering the current step action in the wasm
interpreter handle in WasmDebugInfo, and using it when continuing
execution in the interpreter.
The control flow is as follows: After module compilation, the user sets
a breakpoint in wasm. The respective function is redirected to the
interpreter and the breakpoint is set on the interpreter. When it is
hit, we notify all debug event listeners, which might prepare stepping.
When returning from these listeners, before continuing execution, we
check whether stepping was requested and continue execution in the
interpreter accordingly.

Stepping from Wasm to JS and vice versa will be implemented and tested
in a follow-up CL. Testing this requires breakpoints and stepping in
Wasm to be exposed via the inspector interface, such that we can write
an inspector test. This mixed JS-Wasm-execution is hard to set up in a
cctest.

R=titzer@chromium.org, yangguo@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2649533002
Cr-Commit-Position: refs/heads/master@{#42624}

R=jgruber@chromium.org
BUG=v8:5530

Review-Url: https://codereview.chromium.org/2642253005
Cr-Original-Commit-Position: refs/heads/master@{#42543}
Committed: https://chromium.googlesource.com/v8/v8/+/e26a58e43c51a680a0a6363e0066886f4971a41f
Review-Url: https://codereview.chromium.org/2642253005
Cr-Commit-Position: refs/heads/master@{#42595}

Test that setting breakpoints works for wasm, and that they are hit
correctly.
This basically tests all the layers involved: Compiling and running
wasm interpreter entries, passing arguments to the interpreter, storing
break point infos in wasm objects, getting the right BreakLocation from
wasm frames, and getting stack information from interpreted frames.

BUG=v8:5822
R=titzer@chromium.org, yangguo@chromium.org

Review-Url: https://codereview.chromium.org/2629883002
Cr-Commit-Position: refs/heads/master@{#42560}

Frame inspection is currently limited to locations of execution.
Further details like local variables or stack content will follow later.

The FrameInspector now stores a pointer to the interpreted wasm frame,
and redirects certain requests there, just as for deoptimized frames.
Hitting breakpoints is now also supported for wasm frames.

R=yangguo@chromium.org, titzer@chromium.org
BUG=v8:5822

Review-Url: https://codereview.chromium.org/2629823003
Cr-Commit-Position: refs/heads/master@{#42551}

Our .clang-format is derived on the Google style, which sets
PointerAlignment to left (e.g. "Type* name"), but sets
DerivePointerAlignment to true. Once we started with the wrong style,
this made all new code in wasm-debug.cc use PointerAlignment=right,
resulting in lots of code using the wrong style.

For this CL, I ran
clang-format -style="{DerivePointerAlignment: false, BasedOnStyle: \
  Google}" -i src/wasm/wasm-debug.cc

R=titzer@chromium.org

Review-Url: https://codereview.chromium.org/2635003002
Cr-Commit-Position: refs/heads/master@{#42380}

If a breakpoint is set on a wasm function, compile an interpreter entry
stub for it, and replace all calls to the original function by calls to
this interpreter entry.
Also, instantiate a wasm interpreter object on demand and set the
breakpoint there.

R=titzer@chromium.org
BUG=v8:5822

Review-Url: https://codereview.chromium.org/2625093004
Cr-Commit-Position: refs/heads/master@{#42309}

Also, add a runtime function to call the interpreter, passing a
stack-allocated buffer holding the arguments.
The WASM_INTERPRETER_ENTRY stub allocates the stack slot for the
arguments, fills it, and calls to the wasm interpreter.
It's abi is compatible with WASM functions, such that we can just
replace a call to a WASM_FUNCTION with a call to
WASM_INTERPRETER_ENTRY.
See tracking bug to get the overall picture.

BUG=v8:5822
R=titzer@chromium.org

Review-Url: https://codereview.chromium.org/2619803004
Cr-Commit-Position: refs/heads/master@{#42242}

The new object will hold information which is shared by all clones of a
WasmCompiledModule, e.g. the decoded asm.js offset table, and in the
future also breakpoints. From there, we can set them on each new
instantiation of any clone.

While already changing lots of the code base, I also renamed all
getters from "get_foo" to "foo", to conform to the style guide.

R=titzer@chromium.org, yangguo@chromium.org
BUG=v8:5732

Review-Url: https://codereview.chromium.org/2591653002
Cr-Commit-Position: refs/heads/master@{#41862}

Before, the encoded variant was stored in the compiled module, and the
decoded one in the debug info (per instance).
The decoded table was a FixedArray of ByteArrays.
Now, also the decoded table is a flat ByteArray, and it encodes whether
it is encoded or decoded. This saves memory and allows to store encoded
and decoded variant in the same field. The table is automatically
decoded on the first use.

This CL also removes some unused and unimplemented methods from
WasmDebugInfo (probably merge artifacts). That class is now pretty much
empty, but we might still need it for breakpoint support.

R=titzer@chromium.org, ahaas@chromium.org

Review-Url: https://codereview.chromium.org/2522953002
Cr-Commit-Position: refs/heads/master@{#41316}

Revert of [base] Define CHECK comparison for signed vs. unsigned (patchset #5 id:80001 of https://codereview.chromium.org/2526783002/ )

Reason for revert:
Need to revert previous CL because of Android compile error, and this one depends in it.

Original issue's description:
> [base] Define CHECK comparison for signed vs. unsigned
>
> The current CHECK/DCHECK implementation fails statically if a signed
> value is compared against an unsigned value. The common solution is to
> cast on each caller, which is tedious and error-prone (might hide bugs).
> This CL implements signed vs. unsigned comparisons by executing up to
> two comparisons. For example, if i is int32_t and u is uint_32_t, a
> DCHECK_LE(i, u) would create the check
> i <= 0 || static_cast<uint32_t>(i) <= u.
> For checks against constants, at least one of the checks can be removed
> by compiler optimizations.
>
> The tradeoff we have to make is to sometimes silently execute an
> additional comparison. And we increase code complexity of course, even
> though the usage is just as easy (or even easier) as before.
>
> The compile time impact seems to be minimal:
> I ran 3 full compilations for Optdebug on my local machine, one time on
> the current ToT, one time with this CL plus http://crrev.com/2524093002.
> Before: 143.72 +- 1.21 seconds
> Now: 144.18 +- 0.67 seconds
>
> In order to check that the new comparisons are working, I refactored
> some DCHECKs in wasm to use the new magic.
>
> R=bmeurer@chromium.org, titzer@chromium.org
>
> Committed: https://crrev.com/5925074a9dab5a8577766545b91b62f2c531d3dc
> Cr-Commit-Position: refs/heads/master@{#41275}

TBR=ishell@chromium.org,titzer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review-Url: https://codereview.chromium.org/2531533003
Cr-Commit-Position: refs/heads/master@{#41277}

The current CHECK/DCHECK implementation fails statically if a signed
value is compared against an unsigned value. The common solution is to
cast on each caller, which is tedious and error-prone (might hide bugs).
This CL implements signed vs. unsigned comparisons by executing up to
two comparisons. For example, if i is int32_t and u is uint_32_t, a
DCHECK_LE(i, u) would create the check
i <= 0 || static_cast<uint32_t>(i) <= u.
For checks against constants, at least one of the checks can be removed
by compiler optimizations.

The tradeoff we have to make is to sometimes silently execute an
additional comparison. And we increase code complexity of course, even
though the usage is just as easy (or even easier) as before.

The compile time impact seems to be minimal:
I ran 3 full compilations for Optdebug on my local machine, one time on
the current ToT, one time with this CL plus http://crrev.com/2524093002.
Before: 143.72 +- 1.21 seconds
Now: 144.18 +- 0.67 seconds

In order to check that the new comparisons are working, I refactored
some DCHECKs in wasm to use the new magic.

R=bmeurer@chromium.org, titzer@chromium.org

Review-Url: https://codereview.chromium.org/2526783002
Cr-Commit-Position: refs/heads/master@{#41275}

With the new wasm object types, the GetCompiledModule and GetWasmBytes
functions are not needed any more. The same functions are already
public on the wasm objects.
In order to use them properly, I changed a few more locations to make
use of the new types.

R=ahaas@chromium.org, titzer@chromium.org

Review-Url: https://codereview.chromium.org/2503403005
Cr-Commit-Position: refs/heads/master@{#41085}

Before, we allocated one script per function per instance, and each
script referenced the wasm instance and the function index. Now we only
allocate one script per compiled wasm module, so the script also only
references this WasmCompiledModule, which causes changes to many interfaces.

Instead of fixing the disassemble API only used via debug.js, I decided
to drop it for now. Some later CL will reintroduce it via
DebugInterface.

BUG=v8:5530,chromium:659715
R=yangguo@chromium.org, titzer@chromium.org
CC=jgruber@chromium.org

Review-Url: https://codereview.chromium.org/2493823003
Cr-Commit-Position: refs/heads/master@{#41004}

This CL moves all heap-allocated WASM data structures, both ones
that are bonafide JSObjects and ones that are FixedArrays only, into a
consistent place with consistent layout. Note that not all accessors are complete, and I haven't fully spread the new static typing goodness
to all places in the code.

R=ahaas@chromium.org,rossberg@chromium.org
CC=gdeepti@chromium.org,mtrofin@chromium.org,clemensh@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2490663002
Cr-Commit-Position: refs/heads/master@{#40913}

And add a test case for more than one entry ;)

R=titzer@chromium.org,ahaas@chromium.org

Review-Url: https://codereview.chromium.org/2448833004
Cr-Commit-Position: refs/heads/master@{#40553}

R=clemensh@chromium.org,ahaas@chromium.org
BUG=

Review-Url: https://chromiumcodereview.appspot.com/2428343005
Cr-Commit-Position: refs/heads/master@{#40426}

For the asm.js to WASM pipeline, the current stack traces only show
low-level WASM information.
This CL maps this back to asm.js source positions.
It does so by attaching the asm.js source Script to the compiled WASM
module, and emitting a delta-encoded table which maps from WASM byte
offsets to positions within that Script. As asm.js code does not throw
exceptions, we only store a mapping for call instructions.

The new AsmJsWasmStackFrame implementation inherits from
WasmStackFrame, but contains the logic to provide the source script and
the position inside of it.
What is still missing is the JSFunction object returned by
CallSite.getFunction(). We currently return null.

R=jgruber@chromium.org, titzer@chromium.org
BUG=v8:4203

Review-Url: https://codereview.chromium.org/2404253002
Cr-Commit-Position: refs/heads/master@{#40205}

Use information in the WasmCompiledModule instead.

R=titzer@chromium.org,mtrofin@chromium.org

Review-Url: https://codereview.chromium.org/2396043002
Cr-Commit-Position: refs/heads/master@{#40062}

[0xC] Convert to stack machine semantics.
[0xC] Use section codes instead of names.
[0xC] Add elements section decoding.
[0xC] Decoding of globals section.
[0xC] Decoding of memory section.
[0xC] Decoding of imports section.
[0xC] Decoding of exports section.
[0xC] Decoding of data section.
[0xC] Remove CallImport bytecode.
[0xC] Function bodies have an implicit block.
[0xC] Remove the bottom label from loops.
[0xC] Add signatures to blocks.
[0xC] Remove arities from branches.
Add tests for init expression decoding.
Rework compilation of import wrappers and how they are patched.
Rework function indices in debugging.
Fix ASM->WASM builder for stack machine.
Reorganize asm.js foreign functions due to import indices change.

R=ahaas@chromium.org,rossberg@chromium.org,bradnelson@chromium.org
BUG=chromium:575167
LOG=Y

Committed: https://crrev.com/76eb976a67273b8c03c744f64ad850b0432554b9
Review-Url: https://codereview.chromium.org/2345593003
Cr-Original-Commit-Position: refs/heads/master@{#39678}
Cr-Commit-Position: refs/heads/master@{#39795}

Revert of [wasm] Master CL for Binary 0xC changes. (patchset #26 id:490001 of https://codereview.chromium.org/2345593003/ )

Reason for revert:
Main suspect for tsan:
https://build.chromium.org/p/client.v8/builders/V8%20Linux64%20TSAN/builds/11893

Also changes layout tests:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/10036

+mips builder:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Mips%20-%20builder/builds/4032

Original issue's description:
> [wasm] Master CL for Binary 0xC changes.
>
> [0xC] Convert to stack machine semantics.
> [0xC] Use section codes instead of names.
> [0xC] Add elements section decoding.
> [0xC] Decoding of globals section.
> [0xC] Decoding of memory section.
> [0xC] Decoding of imports section.
> [0xC] Decoding of exports section.
> [0xC] Decoding of data section.
> [0xC] Remove CallImport bytecode.
> [0xC] Function bodies have an implicit block.
> [0xC] Remove the bottom label from loops.
> [0xC] Add signatures to blocks.
> [0xC] Remove arities from branches.
> Add tests for init expression decoding.
> Rework compilation of import wrappers and how they are patched.
> Rework function indices in debugging.
> Fix ASM->WASM builder for stack machine.
> Reorganize asm.js foreign functions due to import indices change.
>
> R=ahaas@chromium.org,rossberg@chromium.org,bradnelson@chromium.org
> BUG=chromium:575167
> LOG=Y
>
> Committed: https://crrev.com/76eb976a67273b8c03c744f64ad850b0432554b9
> Cr-Commit-Position: refs/heads/master@{#39678}

TBR=ahaas@chromium.org,bradnelson@chromium.org,mtrofin@chromium.org,rossberg@chromium.org,bradnelson@google.com,titzer@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:575167

Review-Url: https://codereview.chromium.org/2361053004
Cr-Commit-Position: refs/heads/master@{#39685}

[0xC] Convert to stack machine semantics.
[0xC] Use section codes instead of names.
[0xC] Add elements section decoding.
[0xC] Decoding of globals section.
[0xC] Decoding of memory section.
[0xC] Decoding of imports section.
[0xC] Decoding of exports section.
[0xC] Decoding of data section.
[0xC] Remove CallImport bytecode.
[0xC] Function bodies have an implicit block.
[0xC] Remove the bottom label from loops.
[0xC] Add signatures to blocks.
[0xC] Remove arities from branches.
Add tests for init expression decoding.
Rework compilation of import wrappers and how they are patched.
Rework function indices in debugging.
Fix ASM->WASM builder for stack machine.
Reorganize asm.js foreign functions due to import indices change.

R=ahaas@chromium.org,rossberg@chromium.org,bradnelson@chromium.org
BUG=chromium:575167
LOG=Y

Review-Url: https://codereview.chromium.org/2345593003
Cr-Commit-Position: refs/heads/master@{#39678}

This is some initial cleanup to keep /src clean. The
AccountingAllocator is actually exclusively used by zones and this
common subfolder makes that more clear.

BUG=v8:5409

Review-Url: https://codereview.chromium.org/2344143003
Cr-Commit-Position: refs/heads/master@{#39558}

This disables notification of wasm script 'compilation' since
OnAfterCompile actually triggers a JS call (which is disallowed during
stack trace collection).

BUG=641065

Review-Url: https://codereview.chromium.org/2304943002
Cr-Commit-Position: refs/heads/master@{#39139}

This stores the wasm object and the function index in the script, and
adds functions to get the disassembled wasm code as well as the offset
table mapping from byte position to line and column in the disassembly
solely from the script.
This will be used to show "ui source code" in DevTools, and map raw
locations from the stack trace into this code view.

R=yangguo@chromium.org, ahaas@chromium.org, titzer@chromium.org
BUG=chromium:613110

patch from issue 2063013004 at patchset 80001 (http://crrev.com/2063013004#ps80001)

Review-Url: https://codereview.chromium.org/2105303002
Cr-Commit-Position: refs/heads/master@{#37430}

This changes many interfaces to accept StandardFrames instead of
JavaScriptFrames, and use the StackTraceFrameIterator instead of the
JavaScriptFrameIterator.
Also, the detailed frame information array now contains the script in
addition to the function, as wasm frames are not associated to any
javascript function.

This is a rebase of (https://codereview.chromium.org/2069823003/), since clemensh's internship has ended.

R=yangguo@chromium.org,ahaas@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2109093003
Cr-Commit-Position: refs/heads/master@{#37379}

All function which potentially do heap allocations now take a Handle
on a WasmDebugInfo. This unfortunately requires to make some function
static, since otherwise the "this" pointer would not be handlified.

R=ahaas@chromium.org, titzer@chromium.org
BUG=chromium:613110

Review-Url: https://codereview.chromium.org/2074933005
Cr-Commit-Position: refs/heads/master@{#37099}

All debugging-related information is now stored inside a dedicated
object, which is only allocated if debugging support is needed.
This is also where later a reference to the interpreter will be stored
for executing to-be-debugged functions and providing stack inspection.

R=titzer@chromium.org, ahaas@chromium.org
BUG=chromium:613110

Review-Url: https://codereview.chromium.org/2050953003
Cr-Commit-Position: refs/heads/master@{#37055}