AuroraMiddleware/skia2
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

tidy up register allocation

Browse Source 
- stack allocate up to 16 registers (up to 2KB)
   - align the heap fallback without loop
   - assert the heap fallback is aligned

Change-Id: I8d314c29967731a78aeceea179adfc40694f0606
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/218601
Auto-Submit: Mike Klein <mtklein@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
This commit is contained in:
Mike Klein 2019-06-05 12:41:29 -05:00 committed by Skia Commit-Bot
parent e0d90c84e4
commit f1df3979c6
1 changed files with 16 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
src/opts/SkVM_opts.h
View File

@ -34,16 +34,24 @@ namespace SK_OPTS_NS {
F32 f32;
};
// Annoyingly we can't trust that malloc() or new will work with Slot because
// the skvx::Vec types may have alignment greater than what they provide.
// We'll overallocate one extra register so we can align manually.
std::unique_ptr<char[]> regs_buf{ new char[ sizeof(Slot) * (nregs + 1) ]};
Slot few_regs[16];
std::unique_ptr<char[]> many_regs;
uintptr_t addr = (uintptr_t)regs_buf.get();
while (addr & (alignof(Slot) - 1)) {
addr++;
Slot* regs = few_regs;
if (nregs > (int)SK_ARRAY_COUNT(few_regs)) {
// Annoyingly we can't trust that malloc() or new will work with Slot because
// the skvx::Vec types may have alignment greater than what they provide.
// We'll overallocate one extra register so we can align manually.
many_regs.reset(new char[ sizeof(Slot) * (nregs + 1) ]);
uintptr_t addr = (uintptr_t)many_regs.get();
addr += alignof(Slot) -
(addr & (alignof(Slot) - 1));
SkASSERT((addr & (alignof(Slot) - 1)) == 0);
regs = (Slot*)addr;
}
Slot* regs = (Slot*)addr;
auto r = [&](ID id) -> Slot& {
SkASSERT(0 <= id && id < nregs);