Passing a pointer of the needed type, and then reading using
ReadUnalignedValue is pointless, since the compiler can assume
alignment of the pointer value.
This CL fixes the remaining external refs of wasm to take an Address to
a single buffer.

R=ahaas@chromium.org

Bug: v8:7570, v8:3770
Change-Id: If8a7324a4703e1e900cb3c5644baef207e6a371d
Reviewed-on: https://chromium-review.googlesource.com/1023406
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52754}

Instead of passing multiple pointers to input and output, or to two
input values, just pass one pointer which holds all inputs and where
the output is written.
This also reduces the size of generated Turbofan graphs, since only one
stack slot is needed and less arguments are passed to the call.
It also fixes undefined behaviour, since we were passing a pointer e.g.
as {uint64_t*}, but accessed it using {ReadUnalignedValue}. Now we pass
an Address, which does not have any alignment constraints.

R=ahaas@chromium.org

Bug: v8:3770, v8:6600
Change-Id: I54ef80b7e27f77587a9062560c0b3e01d6593e6d
Reviewed-on: https://chromium-review.googlesource.com/1019147
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52702}

The "Address" type is V8's general-purpose type for manipulating memory
addresses. Per the C++ spec, pointer arithmetic and pointer comparisons
are undefined behavior except within the same array; since we generally
don't operate within a C++ array, our general-purpose type shouldn't be
a pointer type.

Bug: v8:3770
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: Ib96016c24a0f18bcdba916dabd83e3f24a1b5779
Reviewed-on: https://chromium-review.googlesource.com/988657
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52601}

These opcodes will always call out to a C function for now.

R=titzer@chromium.org

Bug: v8:6600
Change-Id: I0ba8984d593c0203b46c2814dec4c091754df99a
Reviewed-on: https://chromium-review.googlesource.com/860924
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50551}

This patch normalizes the casing of hexadecimal digits in escape
sequences of the form `\xNN` and integer literals of the form
`0xNNNN`.

Previously, the V8 code base used an inconsistent mixture of uppercase
and lowercase.

Google’s C++ style guide uses uppercase in its examples:
https://google.github.io/styleguide/cppguide.html#Non-ASCII_Characters

Moreover, uppercase letters more clearly stand out from the lowercase
`x` (or `u`) characters at the start, as well as lowercase letters
elsewhere in strings.

BUG=v8:7109
TBR=marja@chromium.org,titzer@chromium.org,mtrofin@chromium.org,mstarzinger@chromium.org,rossberg@chromium.org,yangguo@chromium.org,mlippautz@chromium.org
NOPRESUBMIT=true

Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_chromium_rel_ng
Change-Id: I790e21c25d96ad5d95c8229724eb45d2aa9e22d6
Reviewed-on: https://chromium-review.googlesource.com/804294
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49810}

This is a reland of 7d231e57, fixed to
avoid instantiating CountLeadingZeros for bits==0.

Original change's description:
> [bits] Consolidate Count{Leading,Trailing}Zeros
> 
> Instead of having one method for 32 bit integers and one for 64 bit,
> plus a templatized version to choose from those two, just implement one
> version which handles unsigned integers of any size. Also, make them
> constexpr.
> The Count{Leading,Trailing}Zeros{32,64} methods are kept for now in
> order to keep the amount of code changes small. Also, sometimes it
> improves readability by stating exactly the size of the argument,
> especially for leading zeros (where zero-extending would add more
> leading zeros).
> 
> CountLeadingZeros now uses a binary search inspired implementation
> as proposed in Hacker's Delight. It's more than 20% faster on x64 if
> the builtins are disabled.
> CountTrailingZeros falls back to CountPopulation instead of counting in
> a naive loop. This is ~50% faster.
> 
> R=mstarzinger@chromium.org
> 
> Change-Id: I1d8bf1d7295b930724163248150444bd17fbb34e
> Reviewed-on: https://chromium-review.googlesource.com/741231
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49106}

Change-Id: Icdff2510ec66d1c96a1912cef29d77d8550994ee
Reviewed-on: https://chromium-review.googlesource.com/753903Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49138}

This reverts commit 7d231e57.

Reason for revert: Breaks revert for win-clang:
https://build.chromium.org/p/tryserver.chromium.win/builders/win_clang/builds/342755

Original change's description:
> [bits] Consolidate Count{Leading,Trailing}Zeros
> 
> Instead of having one method for 32 bit integers and one for 64 bit,
> plus a templatized version to choose from those two, just implement one
> version which handles unsigned integers of any size. Also, make them
> constexpr.
> The Count{Leading,Trailing}Zeros{32,64} methods are kept for now in
> order to keep the amount of code changes small. Also, sometimes it
> improves readability by stating exactly the size of the argument,
> especially for leading zeros (where zero-extending would add more
> leading zeros).
> 
> CountLeadingZeros now uses a binary search inspired implementation
> as proposed in Hacker's Delight. It's more than 20% faster on x64 if
> the builtins are disabled.
> CountTrailingZeros falls back to CountPopulation instead of counting in
> a naive loop. This is ~50% faster.
> 
> R=​mstarzinger@chromium.org
> 
> Change-Id: I1d8bf1d7295b930724163248150444bd17fbb34e
> Reviewed-on: https://chromium-review.googlesource.com/741231
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#49106}

TBR=mstarzinger@chromium.org,clemensh@chromium.org

Change-Id: Iceeb35bf9c7539a1013c9bdbc47118008611bef2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/753463Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49123}

Instead of having one method for 32 bit integers and one for 64 bit,
plus a templatized version to choose from those two, just implement one
version which handles unsigned integers of any size. Also, make them
constexpr.
The Count{Leading,Trailing}Zeros{32,64} methods are kept for now in
order to keep the amount of code changes small. Also, sometimes it
improves readability by stating exactly the size of the argument,
especially for leading zeros (where zero-extending would add more
leading zeros).

CountLeadingZeros now uses a binary search inspired implementation
as proposed in Hacker's Delight. It's more than 20% faster on x64 if
the builtins are disabled.
CountTrailingZeros falls back to CountPopulation instead of counting in
a naive loop. This is ~50% faster.

R=mstarzinger@chromium.org

Change-Id: I1d8bf1d7295b930724163248150444bd17fbb34e
Reviewed-on: https://chromium-review.googlesource.com/741231Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49106}

CCalls have significantly less overhead than runtime calls which will improve
runtime performance on programs that make lots of transitions between JS and
Wasm.

Bug: v8:5277
Change-Id: If09dea97f24eb43753847e2b894ebc1ba5168c23
Reviewed-on: https://chromium-review.googlesource.com/688481
Commit-Queue: Eric Holk <eholk@chromium.org>
Reviewed-by: Mircea Trofin <mtrofin@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48297}

TEST=wasm-spec-tests/tests/set_local,wasm-spec-tests/tests/imports
BUG=

Review-Url: https://codereview.chromium.org/2859223004
Cr-Commit-Position: refs/heads/master@{#45279}

Some instructions in WebAssembly trap for some inputs, which means that the
execution is terminated and (at least at the moment) a JavaScript exception is
thrown. Examples for traps are out-of-bounds memory accesses, or integer
divisions by zero.

Without the TrapIf and TrapUnless operators trap check in WebAssembly introduces 5
TurboFan nodes (branch, if_true, if_false, trap-reason constant, trap-position
constant), in addition to the trap condition itself. Additionally, each
WebAssembly function has four TurboFan nodes (merge, effect_phi, 2 phis) whose
number of inputs is linear to the number of trap checks in the function.
Especially for functions with high numbers of trap checks we observe a
significant slowdown in compilation time, down to 0.22 MiB/s in the sqlite
benchmark instead of the average of 3 MiB/s in other benchmarks. By introducing
a TrapIf common operator only a single node is necessary per trap check, in
addition to the trap condition. Also the nodes which are shared between trap
checks (merge, effect_phi, 2 phis) would disappear. First measurements suggest a
speedup of 30-50% on average.

This CL only implements TrapIf and TrapUnless on x64. The implementation is also
hidden behind the --wasm-trap-if flag.

Please take a special look at how the source position is transfered from the
instruction selector to the code generator, and at the context that is used for
the runtime call.

R=titzer@chromium.org

Review-Url: https://codereview.chromium.org/2562393002
Cr-Commit-Position: refs/heads/master@{#41720}

Also unify the Pow implementation somewhat. There are still some
inconsistencies with the FPU version for x64/ia32, but that has
to be resolved separately.

R=ahaas@chromium.org, mvstanton@chromium.org
BUG=v8:5086

Review-Url: https://codereview.chromium.org/2333663002
Cr-Commit-Position: refs/heads/master@{#39368}

Fix failure in mjsunit/wasm/embenchen/box2d on 32-bit architectures that do not support unaligned access.

This test fails because WasmGraphBuilder::BuildCFuncInstruction allocates
space for doubles using StackSlot turbofan operator, but this space is not
guaranteed to be 8 bytes aligned if SP itself is not 8 bytes aligned (which
is the case on 32-bit architectures).

BUG=mjsunit/wasm/embenchen/box2d

Review-Url: https://codereview.chromium.org/2177863002
Cr-Commit-Position: refs/heads/master@{#38039}

This CL more or less reverts commit https://codereview.chromium.org/2107733002/
The use of the MathPow code stub that was introduced by that commit caused
problems on arm64, and the MathPow code stub was also an obstacle in the
implementation of parallel code generation.

In addition this CL turns on the mjsunit/wasm/embenchen tests for arm64
which were turned off because of problems with MathPow on arm64.

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

Review-Url: https://codereview.chromium.org/2166793002
Cr-Commit-Position: refs/heads/master@{#37911}

This patch provides a new implementation of popcnt and ctz in the case
where the platform does not provide these instructions. Instead of
building a TF graph which implements it we now call a C function.

Additionally I turned on additional tests in test-run-wasm-64.cc

R=titzer@chromium.org

Review URL: https://codereview.chromium.org/1857363003

Cr-Commit-Position: refs/heads/master@{#35685}

1) I moved the implementations of the wrapper functions into a new cc
file so that I can use these wrapper functions in tests.

2) I made a generic test for all tests in
test-run-calls-to-external-references.cc. In the new test we only
compare the result of a function call through an external reference with
the result of a direct function call. This is sufficient because we only
want to test function calls through external references work here.
The implementation of these functions are tested somewhere else.

R=titzer@chromium.org

Review URL: https://codereview.chromium.org/1853123002

Cr-Commit-Position: refs/heads/master@{#35289}

On 32-bit systems these instructions are compiled to calls to
C functions. The TF node for the function call is already generated in
the wasm compiler, the lowering of the I64 parameters is done in the
Int64Lowering. We use the return value of the C function to determine
whether the calculation should trap or not.

R=titzer@chromium.org

Review URL: https://codereview.chromium.org/1804513002

Cr-Commit-Position: refs/heads/master@{#34768}

On 32-bit systems I64XConvertFXX instructions are compiled to calls to
C functions. The TF node for the function call is already generated in
the wasm compiler, the lowering of the I64 parameter is done in the
Int64Lowering. We use the return value of the C function to determine
whether the conversion should trap or not.

R=titzer@chromium.org

Review URL: https://codereview.chromium.org/1775903002

Cr-Commit-Position: refs/heads/master@{#34738}

On 32-bit systems FXXXConvertI64 instructions are compiled to calls to
C functions. The TF node for the function call is already generated in
the wasm compiler, the lowering of the I64 parameter is done in the
Int64Lowering.

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

Review URL: https://codereview.chromium.org/1738623003

Cr-Commit-Position: refs/heads/master@{#34487}