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  1. 04 Mar, 2019 1 commit
    • Benedikt Meurer's avatar
      [cleanup] Remove obsolete "one byte data hint" for strings. · 683cf6f4
      Benedikt Meurer authored 
      In the early days of Chrome when we used WebKit there was no support for
ASCII strings on the C++ side, so we put a hint onto these two-byte
strings that said "string only contains one byte data", such that
internally in V8 when these were involved in string operations, we could
instead create the *cheaper* one byte strings.

Nowadays Blink properly supports one-byte string representations and
this additional hint only comes with overhead, since we check it in
quite a few places (i.e. on the hot path for string concatenation), plus
we end up consuming more memory due to the additional string maps.
Removing the hint also frees one bit in the InstanceType zoo for
strings.

This alone improves performance on the `bench-dom-serialize.js` test case
by around **3%**.

Tbr: mstarzinger@chromium.org
Bug: v8:6622, v8:8834, v8:8939
Cq-Include-Trybots: luci.chromium.try:linux-blink-rel
Change-Id: I0753f2859cee7b5a37b6f0da64d8ec39fcb044ff
Doc: https://bit.ly/fast-string-concatenation-in-javascript
Reviewed-on: https://chromium-review.googlesource.com/c/1498478
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60006}
      683cf6f4
  3. 22 Feb, 2019 1 commit
  5. 09 Jan, 2019 1 commit
  7. 26 Dec, 2018 1 commit
  9. 20 Dec, 2018 1 commit
  11. 11 Dec, 2018 1 commit
  13. 04 Dec, 2018 1 commit
  15. 27 Nov, 2018 1 commit
  17. 26 Nov, 2018 1 commit
  19. 22 Nov, 2018 1 commit
  21. 13 Nov, 2018 1 commit
  23. 05 Nov, 2018 1 commit
  25. 31 Oct, 2018 3 commits
  27. 18 Sep, 2018 1 commit
  29. 17 Sep, 2018 1 commit
  31. 14 Sep, 2018 3 commits
  33. 13 Sep, 2018 1 commit
    • Benedikt Meurer's avatar
      [objects] Change String::length field to uint32_t. · c7a0049e
      Benedikt Meurer authored 
      This changes the Name::hash_field and Symbol::flags to uint32_t as
well, so that both Symbols and Strings consume one fewer word on 64-bit
architectures now. More importantly the access to String::length is
always a 32-bit field load now, even with 31-bit Smis (i.e. on ARM or
on 64-bit with pointer compression), so the access should be faster.

Bug: v8:7065, v8:8171
Change-Id: I1a38f4470d62fbeba2b3bc5fcf4ecdbada7d6b8a
Tbr: ulan@chromium.org, yangguo@chromium.org, ishell@chromium.org
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/1224432Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55861}
      c7a0049e
  35. 12 Sep, 2018 6 commits
    • Sathya Gunasekaran's avatar
      Revert "Reland "[objects] Change String::length field to uint32_t."" · 350dfb62
      Sathya Gunasekaran authored 
      This reverts commit a03cec2c.

Reason for revert: https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux64%20GC%20Stress%20-%20custom%20snapshot/21320

Original change's description:
> Reland "[objects] Change String::length field to uint32_t."
> 
> This is a reland of 1f1eb625, the
> breakage on the GCStress bot seems to be unrelated (maybe flushed
> out by this change). We decided to reland to figure out whether it's
> a random flake or really triggered by this particular change.
> 
> Original change's description:
> > [objects] Change String::length field to uint32_t.
> >
> > This changes the Name::hash_field and Symbol::flags to uint32_t as
> > well, so that both Symbols and Strings consume one fewer word on 64-bit
> > architectures now. More importantly the access to String::length is
> > always a 32-bit field load now, even with 31-bit Smis (i.e. on ARM or
> > on 64-bit with pointer compression), so the access should be faster.
> >
> > Bug: v8:7065, v8:8171
> > Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
> > Change-Id: I5523deb1f84ece91fa2fea775d50318bd1300493
> > Reviewed-on: https://chromium-review.googlesource.com/1221288
> > Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> > Reviewed-by: Yang Guo <yangguo@chromium.org>
> > Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> > Reviewed-by: Igor Sheludko <ishell@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#55825}
> 
> Bug: v8:7065, v8:8171
> Tbr: tebbi@chromium.org, yangguo@chromium.org, ishell@chromium.org, ulan@chromium.org
> Change-Id: I2be24ac018591c04c826e7e8db82e007b738d156
> Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
> Reviewed-on: https://chromium-review.googlesource.com/1222308
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#55838}

TBR=yangguo@chromium.org,tebbi@chromium.org,ishell@chromium.org,bmeurer@chromium.org

Change-Id: Ic741c3d407d4257a8c86b3082b9a19e33dc89215
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7065, v8:8171
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/1222368Reviewed-by: 's avatarSathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55839}
      350dfb62
    • Benedikt Meurer's avatar
      Reland "[objects] Change String::length field to uint32_t." · a03cec2c
      Benedikt Meurer authored 
      This is a reland of 1f1eb625, the
breakage on the GCStress bot seems to be unrelated (maybe flushed
out by this change). We decided to reland to figure out whether it's
a random flake or really triggered by this particular change.

Original change's description:
> [objects] Change String::length field to uint32_t.
>
> This changes the Name::hash_field and Symbol::flags to uint32_t as
> well, so that both Symbols and Strings consume one fewer word on 64-bit
> architectures now. More importantly the access to String::length is
> always a 32-bit field load now, even with 31-bit Smis (i.e. on ARM or
> on 64-bit with pointer compression), so the access should be faster.
>
> Bug: v8:7065, v8:8171
> Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
> Change-Id: I5523deb1f84ece91fa2fea775d50318bd1300493
> Reviewed-on: https://chromium-review.googlesource.com/1221288
> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#55825}

Bug: v8:7065, v8:8171
Tbr: tebbi@chromium.org, yangguo@chromium.org, ishell@chromium.org, ulan@chromium.org
Change-Id: I2be24ac018591c04c826e7e8db82e007b738d156
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/1222308Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55838}
      a03cec2c
    • Benedikt Meurer's avatar
      Revert "Reland "[objects] Change String::length field to uint32_t."" · bd69d64d
      Benedikt Meurer authored 
      This reverts commit df6157ae.

Reason for revert: trybots didn't rerun :-/

Original change's description:
> Reland "[objects] Change String::length field to uint32_t."
> 
> This is a reland of 1f1eb625, the
> breakage on the GCStress bot seems to be unrelated (maybe flushed
> out by this change). We decided to reland to figure out whether it's
> a random flake or really triggered by this particular change.
> 
> Original change's description:
> > [objects] Change String::length field to uint32_t.
> >
> > This changes the Name::hash_field and Symbol::flags to uint32_t as
> > well, so that both Symbols and Strings consume one fewer word on 64-bit
> > architectures now. More importantly the access to String::length is
> > always a 32-bit field load now, even with 31-bit Smis (i.e. on ARM or
> > on 64-bit with pointer compression), so the access should be faster.
> >
> > Bug: v8:7065, v8:8171
> > Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
> > Change-Id: I5523deb1f84ece91fa2fea775d50318bd1300493
> > Reviewed-on: https://chromium-review.googlesource.com/1221288
> > Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> > Reviewed-by: Yang Guo <yangguo@chromium.org>
> > Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> > Reviewed-by: Igor Sheludko <ishell@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#55825}
> 
> Tbr: tebbi@chromium.org, yangguo@chromium.org, ishell@chromium.org
> Bug: v8:7065, v8:8171
> Change-Id: I3c7d0b00abb15fa98ab622f9ecd8602fc798cbc3
> Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
> Reviewed-on: https://chromium-review.googlesource.com/1221290
> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#55836}

TBR=ulan@chromium.org,yangguo@chromium.org,tebbi@chromium.org,ishell@chromium.org,bmeurer@chromium.org

Change-Id: Ieaf3be31166abb02e37370ad846c38fa3d114693
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7065, v8:8171
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/1222306Reviewed-by: 's avatarBenedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55837}
      bd69d64d
    • Benedikt Meurer's avatar
      Reland "[objects] Change String::length field to uint32_t." · df6157ae
      Benedikt Meurer authored 
      This is a reland of 1f1eb625, the
breakage on the GCStress bot seems to be unrelated (maybe flushed
out by this change). We decided to reland to figure out whether it's
a random flake or really triggered by this particular change.

Original change's description:
> [objects] Change String::length field to uint32_t.
>
> This changes the Name::hash_field and Symbol::flags to uint32_t as
> well, so that both Symbols and Strings consume one fewer word on 64-bit
> architectures now. More importantly the access to String::length is
> always a 32-bit field load now, even with 31-bit Smis (i.e. on ARM or
> on 64-bit with pointer compression), so the access should be faster.
>
> Bug: v8:7065, v8:8171
> Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
> Change-Id: I5523deb1f84ece91fa2fea775d50318bd1300493
> Reviewed-on: https://chromium-review.googlesource.com/1221288
> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#55825}

Tbr: tebbi@chromium.org, yangguo@chromium.org, ishell@chromium.org
Bug: v8:7065, v8:8171
Change-Id: I3c7d0b00abb15fa98ab622f9ecd8602fc798cbc3
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/1221290
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55836}
      df6157ae
    • Leszek Swirski's avatar
      Revert "[objects] Change String::length field to uint32_t." · 4bbb7c4e
      Leszek Swirski authored 
      This reverts commit 1f1eb625.

Reason for revert: GC Stress failure (https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux64%20GC%20Stress%20-%20custom%20snapshot/21311) 

Original change's description:
> [objects] Change String::length field to uint32_t.
> 
> This changes the Name::hash_field and Symbol::flags to uint32_t as
> well, so that both Symbols and Strings consume one fewer word on 64-bit
> architectures now. More importantly the access to String::length is
> always a 32-bit field load now, even with 31-bit Smis (i.e. on ARM or
> on 64-bit with pointer compression), so the access should be faster.
> 
> Bug: v8:7065, v8:8171
> Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
> Change-Id: I5523deb1f84ece91fa2fea775d50318bd1300493
> Reviewed-on: https://chromium-review.googlesource.com/1221288
> Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#55825}

TBR=yangguo@chromium.org,tebbi@chromium.org,ishell@chromium.org,bmeurer@chromium.org

Change-Id: I73f3200902f9d52e5664d48c938e37d9dfb7bce7
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:7065, v8:8171
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/1221706Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55826}
      4bbb7c4e
    • Benedikt Meurer's avatar
      [objects] Change String::length field to uint32_t. · 1f1eb625
      Benedikt Meurer authored 
      This changes the Name::hash_field and Symbol::flags to uint32_t as
well, so that both Symbols and Strings consume one fewer word on 64-bit
architectures now. More importantly the access to String::length is
always a 32-bit field load now, even with 31-bit Smis (i.e. on ARM or
on 64-bit with pointer compression), so the access should be faster.

Bug: v8:7065, v8:8171
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng;luci.v8.try:v8_linux_noi18n_rel_ng
Change-Id: I5523deb1f84ece91fa2fea775d50318bd1300493
Reviewed-on: https://chromium-review.googlesource.com/1221288
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: 's avatarYang Guo <yangguo@chromium.org>
Reviewed-by: 's avatarTobias Tebbi <tebbi@chromium.org>
Reviewed-by: 's avatarIgor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55825}
      1f1eb625
  37. 11 Sep, 2018 1 commit
  39. 27 Aug, 2018 1 commit
  41. 24 Aug, 2018 1 commit
  43. 26 Jul, 2018 1 commit
  45. 25 Jul, 2018 1 commit
  47. 24 Jul, 2018 2 commits
  49. 13 Jul, 2018 1 commit
    • Michael Lippautz's avatar
      Revert "Reland "[heap] Added External Strings to external memory accounting."" · 71dddd14
      Michael Lippautz authored 
      This reverts commit 7bff339e.

Reason for revert: Breaks autoroll, see bug.

Bug: v8:7944

Original change's description:
> Reland "[heap] Added External Strings to external memory accounting."
> 
> This is a reland of 5863c0b6
> 
> Original change's description:
> > [heap] Added External Strings to external memory accounting.
> > 
> > Bug: chromium:845409
> > Change-Id: I3fe2b294f6e038d77787cf0870d244ba7cc20550
> > Reviewed-on: https://chromium-review.googlesource.com/1118164
> > Commit-Queue: Rodrigo Bruno <rfbpb@google.com>
> > Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#54110}
> 
> Bug: chromium:845409
> Change-Id: Ied341ec6268000343d2a577b22f2a483460b01f5
> Reviewed-on: https://chromium-review.googlesource.com/1121736
> Commit-Queue: Rodrigo Bruno <rfbpb@google.com>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
> Reviewed-by: Hannes Payer <hpayer@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#54410}

TBR=ulan@chromium.org,hpayer@chromium.org,mlippautz@chromium.org,petermarshall@chromium.org,rfbpb@google.com

Change-Id: Ie55586e84f44a2d83c7f97110d60abb86f0730c5
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:845409
Reviewed-on: https://chromium-review.googlesource.com/1136312Reviewed-by: 's avatarMichael Lippautz <mlippautz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54428}
      71dddd14
  51. 12 Jul, 2018 2 commits
  53. 22 Jun, 2018 1 commit
  55. 21 Jun, 2018 1 commit
  57. 14 May, 2018 1 commit