There was a scheduling race where a child may not increment the global task
count before the parent exits, and the parent would then think that there are no
more tasks left.
LLVM appears to generate calls to exp10 on ARM and bionic does not define it.
This makes code that links to libextra (which I guess does some exponentiation on the stat module) link correctly.
In a multi-host build the mklldeps.py tool is getting called before
all the llvm-configs are built. I am not actually sure the cause. I
had convinced myself that DEF_LLVM_RULES needed to be called before
the llvmdeps.rs rule, but now looking at it again I can't see why.
Here's the error: http://buildbot.rust-lang.org/builders/dist2-linux/builds/11/steps/compile/logs/stdio
r? @alexcrichton
Previously this was an `rtabort!`, indicating a runtime bug. Promote
this to a more intentional abort and print a (slightly) more
informative error message.
Can't test this sense our test suite can't handle an abort exit.
I consider this to close#910, and that we should open another issue about implementing less conservative semantics here.
After writing some benchmarks for ebml::reader::vuint_at() I noticed that LLVM doesn't seem to inline the from_be32 function even though it only does a call to the bswap32 intrinsic in the x86_64 case. Marking the functions with #[inline(always)] fixes that and seems to me a reasonable thing to do. I got the following measurements in my vuint_at() benchmarks:
- Before
test ebml::bench::vuint_at_A_aligned ... bench: 1075 ns/iter (+/- 58)
test ebml::bench::vuint_at_A_unaligned ... bench: 1073 ns/iter (+/- 5)
test ebml::bench::vuint_at_D_aligned ... bench: 1150 ns/iter (+/- 5)
test ebml::bench::vuint_at_D_unaligned ... bench: 1151 ns/iter (+/- 6)
- Inline from_be32
test ebml::bench::vuint_at_A_aligned ... bench: 769 ns/iter (+/- 9)
test ebml::bench::vuint_at_A_unaligned ... bench: 795 ns/iter (+/- 6)
test ebml::bench::vuint_at_D_aligned ... bench: 758 ns/iter (+/- 8)
test ebml::bench::vuint_at_D_unaligned ... bench: 759 ns/iter (+/- 8)
- Using vuint_at_slow()
test ebml::bench::vuint_at_A_aligned ... bench: 646 ns/iter (+/- 7)
test ebml::bench::vuint_at_A_unaligned ... bench: 645 ns/iter (+/- 3)
test ebml::bench::vuint_at_D_aligned ... bench: 907 ns/iter (+/- 4)
test ebml::bench::vuint_at_D_unaligned ... bench: 1085 ns/iter (+/- 16)
As expected inlining from_be32() gave a considerable speedup.
I also tried how the "slow" version fared against the optimized version and noticed that it's
actually a bit faster for small A class integers (using only two bytes) but slower for big D class integers (using four bytes)
In a multi-host build the mklldeps.py tool is getting called before
all the llvm-configs are built. I am not actually sure the cause. I
had convinced myself that DEF_LLVM_RULES needed to be called before
the llvmdeps.rs rule, but now looking at it again I can't see why.
