| commit | 215e81a7a30d6540db1e42193ed6936850a81b9e | |
| author | Douglas Katzman <dougk@google.com> | |
| Thu, 13 Oct 2016 23:33:27 +0000 (13 19:33 -0400) | ||
| committer | Douglas Katzman <dougk@google.com> | |
| Thu, 13 Oct 2016 23:33:27 +0000 (13 19:33 -0400) | ||
| tree | 8da82605a0a195c1914957729eb580475da03e9f | treesnapshot (tar.gz zip) |
| parent | ecac4a456331b0807b77193f294092c4dfc62048 | commitdiff |
Add :compact-instance-header feature for x86-64.
This is part 2 of 4 of the overall immobile space feature.
The immobile allocator places all layouts below 4GB so that
a 32-bit pointer suffices to address them, which in turn allows
stuffing a layout pointer into an instance header.
In practical terms this yields either a 0-word or 2-word reduction
in the number of slots, depending on presence of trailing padding.
The feature is enabled by default on supported platforms.
This is part 2 of 4 of the overall immobile space feature.
The immobile allocator places all layouts below 4GB so that
a 32-bit pointer suffices to address them, which in turn allows
stuffing a layout pointer into an instance header.
In practical terms this yields either a 0-word or 2-word reduction
in the number of slots, depending on presence of trailing padding.
The feature is enabled by default on supported platforms.
20 files changed: