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  1. 12 Dec, 2017 34 commits
  3. 11 Dec, 2017 6 commits
    • Sergiy Byelozyorov's avatar
      Whitespace CL · e5d1ff25
      Sergiy Byelozyorov authored 
      TBR=sergiyb@chromium.org

Bug: chromium:747960
Change-Id: I3767d335907f2b953b633c4ae20c5c9b2dc5d65b
Reviewed-on: https://chromium-review.googlesource.com/820910
Commit-Queue: Sergiy Byelozyorov <sergiyb@chromium.org>
Reviewed-by: 's avatarSergiy Byelozyorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50017}
      e5d1ff25
    • Junliang Yan's avatar
      PPC/s390: [wasm] Cleanup Ifdefs for SIMD ops · 4473c58b
      Junliang Yan authored 
      Port 663b55aa

R=gdeepti@chromium.org, joransiu@ca.ibm.com, jbarboza@ca.ibm.com
BUG=
LOG=N

Change-Id: Ia8cfa8c0927915c4afa07ceac85140231c415a9b
Reviewed-on: https://chromium-review.googlesource.com/820196Reviewed-by: 's avatarDeepti Gandluri <gdeepti@chromium.org>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#50016}
      4473c58b
    • Sergiy Byelozyorov's avatar
      [tools] Migrate 3 more pairs of builders to LUCI · 91021b72
      Sergiy Byelozyorov authored 
      TBR=machenbach@google.com

No-Try: true
Bug: chromium:747960
Change-Id: I3ec105f0ddc2856c95b2314c4e2dd285e040b330
Reviewed-on: https://chromium-review.googlesource.com/820830
Commit-Queue: Sergiy Byelozyorov <sergiyb@chromium.org>
Reviewed-by: 's avatarSergiy Byelozyorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50015}
      91021b72
    • Deepti Gandluri's avatar
      [wasm] Implement wasm SIMD F32x4 Ops · 7fd5949c
      Deepti Gandluri authored 
      This patch implements the following F32x4 Ops:
F32x4Splat, F32x4ExtractLane, F32x4ReplaceLane
F32x4RecipApprox, F32x4RecipSqrtApprox
F32x4Add, F32x4Sub, F32x4Mul, F32x4Min, F32x4Max,
F32x4Eq, F32x4Ne, F32x4Gt, F32x4Ge

BUG=V8:6020

Change-Id: I8267734d336f4bae6fed008d7b1f5faa428574df
Reviewed-on: https://chromium-review.googlesource.com/816734Reviewed-by: 's avatarBill Budge <bbudge@chromium.org>
Reviewed-by: 's avatarMircea Trofin <mtrofin@chromium.org>
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50014}
      7fd5949c
    • Deepti Gandluri's avatar
      Implement haddps for ia32/x64 · d3ed12b4
      Deepti Gandluri authored 
      The haddps instruction is needed to implement wasm SIMD F32x4 horizontal add.

BUG=V8:6020

Change-Id: Ifff78f6c697b46e621f0fd6b7bb1b0e7824a3088
Reviewed-on: https://chromium-review.googlesource.com/820098Reviewed-by: 's avatarBill Budge <bbudge@chromium.org>
Commit-Queue: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50013}
      d3ed12b4
    • Justin Ridgewell's avatar
      Implement DFA Unicode Decoder · cedec225
      Justin Ridgewell authored 
      This is a separation of the DFA Unicode Decoder from
https://chromium-review.googlesource.com/c/v8/v8/+/789560

I attempted to make the DFA's table a bit more explicit in this CL. Still, the
linter prevents me from letting me present the array as a "table" in source
code. For a better representation, please refer to
https://docs.google.com/spreadsheets/d/1L9STtkmWs-A7HdK5ZmZ-wPZ_VBjQ3-Jj_xN9c6_hLKA

- - - - -

Now for a big copy-paste from 789560:

Essentially, reworks a standard FSM (imagine an
array of structs) and flattens it out into a single-dimension array.
Using Table 3-7 of the Unicode 10.0.0 standard (page 126 of
http://www.unicode.org/versions/Unicode10.0.0/ch03.pdf), we can nicely
map all bytes into one of 12 character classes:

00. 0x00-0x7F
01. 0x80-0x8F (split from general continuation because this range is not
    valid after a 0xF0 leading byte)
02. 0x90-0x9F (split from general continuation because this range is not
    valid after a 0xE0 nor a 0xF4 leading byte)
03. 0xA0-0xBF (the rest of the continuation range)
04. 0xC0-0xC1, 0xF5-0xFF (the joined range of invalid bytes, notice this
    includes 255 which we use as a known bad byte during hex-to-int
        decoding)
05. 0xC2-0xDF (leading bytes which require any continuation byte
    afterwards)
06. 0xE0 (leading byte which requires a 0xA0-0xBF afterwards then any
    continuation byte after that)
07. 0xE1-0xEC, 0xEE-0xEF (leading bytes which requires any continuation
    afterwards then any continuation byte after that)
08. 0xED (leading byte which requires a 0x80-0x9F afterwards then any
    continuation byte after that)
09. 0xF1-F3 (leading bytes which requires any continuation byte
    afterwards then any continuation byte then any continuation byte)
10. 0xF0 (leading bytes which requires a 0x90-0xBF afterwards then any
    continuation byte then any continuation byte)
11. 0xF4 (leading bytes which requires a 0x80-0x8F afterwards then any
    continuation byte then any continuation byte)

Note that 0xF0 and 0xF1-0xF3 were swapped so that fewer bytes were
needed to represent the transition state ("9, 10, 10, 10" vs.
"10, 9, 9, 9").

Using these 12 classes as "transitions", we can map from one state to
the next. Each state is defined as some multiple of 12, so that we're
always starting at the 0th column of each row of the FSM. From each
state, we add the transition and get a index of the new row the FSM is
entering.

If at any point we encounter a bad byte, the state + bad-byte-transition
is guaranteed to map us into the first row of the FSM (which contains no
valid exiting transitions).

The key differences from Björn's original (or his self-modified) DFA is
the "bad" state is now mapped to 0 (or the first row of the FSM) instead
of 12 (the second row). This saves ~50 bytes when gzipping, and also
speeds up determining if a string is properly encoded (see his sample
code at http://bjoern.hoehrmann.de/utf-8/decoder/dfa/#performance).

Finally, I've replace his ternary check with an array access, to make
the algorithm branchless. This places a requirement on the caller to 0
out the code point between successful decodings, which it could always
have done because it's already branching.

R=marja@google.com

Bug: 
Change-Id: I574f208a84dc5d06caba17127b0d41f7ce1a3395
Reviewed-on: https://chromium-review.googlesource.com/805357
Commit-Queue: Justin Ridgewell <jridgewell@google.com>
Reviewed-by: 's avatarMarja Hölttä <marja@chromium.org>
Reviewed-by: 's avatarMathias Bynens <mathias@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50012}
      cedec225