Commit Graph

929 Commits

Author SHA1 Message Date
Petr Hosek
0ab14951db [NFC][libc] Use the new style includes for tests
This was accidentally omitted from D154746.
2023-07-10 07:42:13 +00:00
Petr Hosek
fb149e4beb [libc] Use the new style includes for tests
This is a follow up to D154529 covering tests.

Differential Revision: https://reviews.llvm.org/D154746
2023-07-08 05:15:44 +00:00
Petr Hosek
9654bc3960 Revert "[libc] Set include directories for the str_to_float test"
This reverts commit 147c0640a3 since
it broke GPU builds.
2023-07-07 21:25:23 +00:00
Petr Hosek
147c0640a3 [libc] Set include directories for the str_to_float test
This test uses libc headers and need to explicitly include them.

Differential Revision: https://reviews.llvm.org/D154277
2023-07-07 20:33:54 +00:00
Joseph Huber
c850ea1498 [libc] Support fopen / fclose on the GPU
This patch adds the necessary support for the fopen and fclose functions
to work on the GPU via RPC. I added a new test that enables testing this
with the minimal features we have on the GPU. I will update it once we
have `fread` and `fwrite` to actually check the outputted strings. For
now I just relied on checking manually via the outpuot temp file.

Reviewed By: JonChesterfield, sivachandra

Differential Revision: https://reviews.llvm.org/D154519
2023-07-05 18:31:58 -05:00
Joseph Huber
7e88e26d38 [libc] Add GPU support for the 'inttypes.h' functions
Another low hanging fruit we can put on the GPU, this ports the tests
over to the hermetic framework so we can run them on the GPU.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D154540
2023-07-05 17:47:10 -05:00
Joseph Huber
515bd1c9b8 [libc][Obvious] Fix timing on AMDGPU not being initialized
Summary:
Reviewer requested that this routine not be a macro, however that means
that it was not being intitialized as the static initializer was done
before the memcpy from the device. Fix this so we can get timing
information.
2023-07-05 16:08:37 -05:00
Joseph Huber
80504b06ad [libc][Obvious] Fix bad macro check on NVPTX tests
Summary:
I forgot to add the `defined()` check on NVPTX.
2023-07-05 15:54:12 -05:00
Joseph Huber
5db39796bf [libc] Support timing information in libc tests
This patch adds the necessary support to provide timing information in
`libc` tests. This is useful for determining which tests look what
amount of time. We also can use this as a test basis for providing more
fine-grained timing when implementing things on the GPU.

The main difficulty with this is the fact that the AMDGPU fixed
frequency clock operates at an unknown frequency. We need to read this
on a per-card basis from the driver and then copy it in. NVPTX on the
other hand has a fixed clock at a resolution of 1ns. I have also
increased the resolution of the print-outs as the majority of these are
below a millisecond for me.

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D154446
2023-07-05 14:27:08 -05:00
Siva Chandra
3db36d6a9b [libc] Initiliaze the global pointer in riscv startup code.
Reviewed By: mikhail.ramalho

Differential Revision: https://reviews.llvm.org/D151539
2023-07-05 07:32:31 +00:00
Guillaume Chatelet
1c814c99aa [libc] Improve memcmp latency and codegen
This is based on ideas from @nafi to:
 - use a branchless version of 'cmp' for 'uint32_t',
 - completely resolve the lexicographic comparison through vector
   operations when wide types are available. We also get rid of byte
   reloads and serializing '__builtin_ctzll'.

I did not include the suggestion to replace comparisons of 'uint16_t'
with two 'uint8_t' as it did not seem to help the codegen. This can
be revisited in sub-sequent patches.

The code been rewritten to reduce nested function calls, making the
job of the inliner easier and preventing harmful code duplication.

Reviewed By: nafi3000

Differential Revision: https://reviews.llvm.org/D148717
2023-06-30 13:00:58 +00:00
Tue Ly
de19101e33 [libc][NFC] Set rounding mode for sincosf exhaustive test. 2023-06-28 20:30:54 -04:00
Tue Ly
f320fefc4a [libc][math] Implement erff function correctly rounded to all rounding modes.
Implement correctly rounded `erff` functions.

For `x >= 4`, `erff(x) = 1` for `FE_TONEAREST` or `FE_UPWARD`, `0x1.ffffep-1` for `FE_DOWNWARD` or `FE_TOWARDZERO`.

For `0 <= x < 4`, we divide into 32 sub-intervals of length `1/8`, and use a degree-15 odd polynomial to approximate `erff(x)` in each sub-interval:
```
  erff(x) ~ x * (c0 + c1 * x^2 + c2 * x^4 + ... + c7 * x^14).
```

For `x < 0`, we can use the same formula as above, since the odd part is factored out.

Performance tested with `perf.sh` tool from the CORE-MATH project on AMD Ryzen 9 5900X:

Reciprocal throughput (clock cycles / op)
```
$ ./perf.sh erff --path2
GNU libc version: 2.35
GNU libc release: stable
-- CORE-MATH reciprocal throughput --  with -march=native      (with FMA instructions)
[####################] 100 %
Ntrial = 20 ; Min = 11.790 + 0.182 clc/call; Median-Min = 0.154 clc/call; Max = 12.255 clc/call;
-- CORE-MATH reciprocal throughput --  with -march=x86-64-v2      (without FMA instructions)
[####################] 100 %
Ntrial = 20 ; Min = 14.205 + 0.151 clc/call; Median-Min = 0.159 clc/call; Max = 15.893 clc/call;

-- System LIBC reciprocal throughput --
[####################] 100 %
Ntrial = 20 ; Min = 45.519 + 0.445 clc/call; Median-Min = 0.552 clc/call; Max = 46.345 clc/call;

-- LIBC reciprocal throughput --  with -mavx2 -mfma     (with FMA instructions)
[####################] 100 %
Ntrial = 20 ; Min = 9.595 + 0.214 clc/call; Median-Min = 0.220 clc/call; Max = 9.887 clc/call;
-- LIBC reciprocal throughput --  with -msse4.2     (without FMA instructions)
[####################] 100 %
Ntrial = 20 ; Min = 10.223 + 0.190 clc/call; Median-Min = 0.222 clc/call; Max = 10.474 clc/call;
```

and latency (clock cycles / op):
```
$ ./perf.sh erff --path2
GNU libc version: 2.35
GNU libc release: stable
-- CORE-MATH latency --  with -march=native      (with FMA instructions)
[####################] 100 %
Ntrial = 20 ; Min = 38.566 + 0.391 clc/call; Median-Min = 0.503 clc/call; Max = 39.170 clc/call;
-- CORE-MATH latency --  with -march=x86-64-v2      (without FMA instructions)
[####################] 100 %
Ntrial = 20 ; Min = 43.223 + 0.667 clc/call; Median-Min = 0.680 clc/call; Max = 43.913 clc/call;

-- System LIBC latency --
[####################] 100 %
Ntrial = 20 ; Min = 111.613 + 1.267 clc/call; Median-Min = 1.696 clc/call; Max = 113.444 clc/call;

-- LIBC latency --  with -mavx2 -mfma     (with FMA instructions)
[####################] 100 %
Ntrial = 20 ; Min = 40.138 + 0.410 clc/call; Median-Min = 0.536 clc/call; Max = 40.729 clc/call;
-- LIBC latency --  with -msse4.2     (without FMA instructions)
[####################] 100 %
Ntrial = 20 ; Min = 44.858 + 0.872 clc/call; Median-Min = 0.814 clc/call; Max = 46.019 clc/call;
```

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D153683
2023-06-28 13:58:37 -04:00
Tue Ly
e9074d019e [libc] Fix missing dependency and linking option for sqrtf exhaustive test. 2023-06-28 08:13:53 -04:00
Tue Ly
9532074a9d [libc][math] Clean up exhaustive tests implementations.
Clean up exhaustive tests.  Let check functions return number of failures instead of passed/failed.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D153682
2023-06-28 07:58:46 -04:00
Jon Chesterfield
d4d8cd8446 [libc] Factor specifics of packet type out of process
NFC. Simplifies process slightly, gives more options for testing it.

Reviewed By: jhuber6

Differential Revision: https://reviews.llvm.org/D153604
2023-06-23 03:45:23 +01:00
Jon Chesterfield
85c66f5d18 [libc] Instantiate and sanity check rpc class
CMake plumbing cargo culted from other tests.
Minor changes to Process to allow statically allocating a buffer.

Reviewed By: jhuber6

Differential Revision: https://reviews.llvm.org/D153594
2023-06-23 02:11:18 +01:00
Guillaume Chatelet
bd1cba9f4f Revert D148717 "[libc] Improve memcmp latency and codegen"
Once integrated in our codebase the patch triggered a bunch of failing
tests. We do not yet understand where the bug is but we revert it to
move forward with integration.
This reverts commit 5e32765c15.
2023-06-21 12:37:14 +00:00
Siva Chandra Reddy
75d70b7306 [libc] Make close function of the internal File class cleanup the file object.
Before this change, a separate static method named cleanup was used to
cleanup the file. Instead, now the close method cleans up the full file
object using the platform's close function.

Reviewed By: lntue

Differential Revision: https://reviews.llvm.org/D153377
2023-06-21 05:05:04 +00:00
Mikhail R. Gadelha
a2df87c2b0 [libc] Fix libmath test compilation when using UInt<T>
This patch:
(1) adds the add_with_carry_const and sub_with_borrow_const constexpr calls
to add and sub, respectively. Both add and sub are constexpr calls and
were call the non-constexpr version of add/sub_with_borrow.
(2) adds explicit UIntType construct calls in some fp tests.

Reviewed By: lntue

Differential Revision: https://reviews.llvm.org/D150223
2023-06-20 15:41:18 -03:00
Tue Ly
5dbd5118ec [libc][math] Improve tanhf performance.
Re-order exceptional branches and slightly adjust the evaluation.

Performance tested with the CORE-MATH project on AMD EPYC 7B12 (clocks/op)

Reciprocal throughputs:
```
--- BEFORE ---

$ CORE_MATH_PERF_MODE=rdtsc ./perf.sh tanhf
[####################] 100 %  (with -mavx2 -mfma)
Ntrial = 20 ; Min = 7.794 + 0.102 clc/call; Median-Min = 0.066 clc/call; Max = 8.267 clc/call;
[####################] 100 %. (with -msse4.2)
Ntrial = 20 ; Min = 10.783 + 0.172 clc/call; Median-Min = 0.144 clc/call; Max = 11.446 clc/call;
[####################] 100 %. (SSE2)
Ntrial = 20 ; Min = 18.926 + 0.381 clc/call; Median-Min = 0.342 clc/call; Max = 19.623 clc/call;

--- AFTER ---

$ CORE_MATH_PERF_MODE=rdtsc ./perf.sh tanhf
[####################] 100 %  (with -mavx2 -mfma)
Ntrial = 20 ; Min = 6.598 + 0.085 clc/call; Median-Min = 0.052 clc/call; Max = 6.868 clc/call;
[####################] 100 %  (with -msse4.2)
Ntrial = 20 ; Min = 9.245 + 0.304 clc/call; Median-Min = 0.248 clc/call; Max = 10.675 clc/call;
[####################] 100 %. (SSE2)
Ntrial = 20 ; Min = 11.724 + 0.440 clc/call; Median-Min = 0.444 clc/call; Max = 12.262 clc/call;
```

Latency:
```
--- BEFORE ---

$ PERF_ARGS="--latency" CORE_MATH_PERF_MODE=rdtsc ./perf.sh tanhf
[####################] 100 %  (with -mavx2 -mfma)
Ntrial = 20 ; Min = 38.821 + 0.157 clc/call; Median-Min = 0.122 clc/call; Max = 39.539 clc/call;
[####################] 100 %. (with -msse4.2)
Ntrial = 20 ; Min = 44.767 + 0.766 clc/call; Median-Min = 0.681 clc/call; Max = 45.951 clc/call;
[####################] 100 %. (SSE2)
Ntrial = 20 ; Min = 55.055 + 1.512 clc/call; Median-Min = 1.571 clc/call; Max = 57.039 clc/call;

--- AFTER ---

$ PERF_ARGS="--latency" CORE_MATH_PERF_MODE=rdtsc ./perf.sh tanhf
[####################] 100 %  (with -mavx2 -mfma)
Ntrial = 20 ; Min = 36.147 + 0.194 clc/call; Median-Min = 0.181 clc/call; Max = 36.536 clc/call;
[####################] 100 %  (with -msse4.2)
Ntrial = 20 ; Min = 40.904 + 0.728 clc/call; Median-Min = 0.557 clc/call; Max = 42.231 clc/call;
[####################] 100 %. (SSE2)
Ntrial = 20 ; Min = 55.776 + 0.557 clc/call; Median-Min = 0.542 clc/call; Max = 56.551 clc/call;
```

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D153026
2023-06-20 09:25:07 -04:00
Siva Chandra Reddy
21e1651c0c [libc] Remove the requirement of a platform-flush operation in File abstraction.
The libc flush operation is not supposed to trigger a platform level
flush operation. See "Notes" on this Linux man page:
    https://man7.org/linux/man-pages/man3/fflush.3.html

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D153182
2023-06-19 18:38:29 +00:00
Joseph Huber
485e2de6d5 [libc][nfc] Silence two warnings in tests
These currently give warnings for unused variables or a default case
where everything is covered.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D153137
2023-06-16 12:52:06 -05:00
Joseph Huber
ed34cb2cd7 [libc] Add a test for fputs to check using stdout and stderr
This patch adds a test directly for the `fputs` function similar to the
existing `puts` test. This lets us know that the default file pointers
are function and the `fputs` interface works.

Reviewed By: lntue

Differential Revision: https://reviews.llvm.org/D152288
2023-06-16 11:01:55 -05:00
Joseph Huber
7e8b0c27f2 [libc] Disable the strtod and strtold tests on NVPTX
These tests have a single line that fails with a value off-by-one, see
https://lab.llvm.org/buildbot/#/builders/46/builds/50055/steps/12/logs/stdio .
Disable these for now so we can figure out what the error is later.

Reviewed By: lntue

Differential Revision: https://reviews.llvm.org/D153056
2023-06-15 13:29:42 -05:00
Joseph Huber
dcdfc963d7 [libc] Export GPU extensions to libc for external use
The GPU port of the LLVM C library needs to export a few extensions to
the interface such that users can interface with it. This patch adds the
necessary logic to define a GPU extension. Currently, this only exports
a `rpc_reset_client` function. This allows us to use the server in
D147054 to set up the RPC interface outside of `libc`.

Depends on https://reviews.llvm.org/D147054

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D152283
2023-06-15 11:02:24 -05:00
Tue Ly
53d4057622 [libc] Fix merging issue with test/src/math/exhaustive/expm1f_test 2023-06-14 11:00:13 -04:00
Tue Ly
055be3c30c [libc] Enable hermetic floating point tests again.
Fixing an issue with LLVM libc's fenv.h defined rounding mode macros
differently from system libc, making get_round() return different values from
fegetround().  Also letting math tests to skip rounding modes that cannot be
set.  This should allow math tests to be run on platforms in which fenv.h is not
implemented yet.

This allows us to re-enable hermatic floating point tests in
https://reviews.llvm.org/D151123 and reverting https://reviews.llvm.org/D152742.

Reviewed By: jhuber6

Differential Revision: https://reviews.llvm.org/D152873
2023-06-14 10:53:35 -04:00
Guillaume Chatelet
9902fc8dad [libc] Enable custom logging in LibcTest
This patch mimics the behavior of Google Test and allow users to log custom messages after all flavors of ASSERT_ / EXPECT_.

Reviewed By: sivachandra, lntue

Differential Revision: https://reviews.llvm.org/D152630
2023-06-14 13:37:50 +00:00
Guillaume Chatelet
bdb07c98c4 Revert D152630 "[libc] Enable custom logging in LibcTest"
Failing buildbot https://lab.llvm.org/buildbot/#/builders/73/builds/49707
This reverts commit 9a7b4c9348.
2023-06-14 10:31:49 +00:00
Guillaume Chatelet
9a7b4c9348 [libc] Enable custom logging in LibcTest
This patch mimics the behavior of Google Test and allow users to log custom messages after all flavors of ASSERT_ / EXPECT_.

Reviewed By: sivachandra, lntue

Differential Revision: https://reviews.llvm.org/D152630
2023-06-14 10:26:18 +00:00
Guillaume Chatelet
2cfae7cdf4 [libc] Dispatch memmove to memcpy when buffers are disjoint
Most of the time `memmove` is called on buffers that are disjoint, in that case we can use `memcpy` which is faster.
The additional test is branchless on x86, aarch64 and RISCV with the zbb extension (bitmanip).
On x86 this patch adds a latency of 2 to 3 cycles.

Before
```
--------------------------------------------------------------------------------
Benchmark                      Time             CPU   Iterations UserCounters...
--------------------------------------------------------------------------------
BM_Memmove/0/0_median       5.00 ns         5.00 ns           10 bytes_per_cycle=1.25477/s bytes_per_second=2.62933G/s items_per_second=199.87M/s __llvm_libc::memmove,memmove Google A
BM_Memmove/1/0_median       6.21 ns         6.21 ns           10 bytes_per_cycle=3.22173/s bytes_per_second=6.75106G/s items_per_second=160.955M/s __llvm_libc::memmove,memmove Google B
BM_Memmove/2/0_median       8.09 ns         8.09 ns           10 bytes_per_cycle=5.31462/s bytes_per_second=11.1366G/s items_per_second=123.603M/s __llvm_libc::memmove,memmove Google D
BM_Memmove/3/0_median       5.95 ns         5.95 ns           10 bytes_per_cycle=2.71865/s bytes_per_second=5.69687G/s items_per_second=167.967M/s __llvm_libc::memmove,memmove Google L
BM_Memmove/4/0_median       5.63 ns         5.63 ns           10 bytes_per_cycle=2.28294/s bytes_per_second=4.78383G/s items_per_second=177.615M/s __llvm_libc::memmove,memmove Google M
BM_Memmove/5/0_median       5.68 ns         5.68 ns           10 bytes_per_cycle=2.16798/s bytes_per_second=4.54295G/s items_per_second=176.015M/s __llvm_libc::memmove,memmove Google Q
BM_Memmove/6/0_median       7.46 ns         7.46 ns           10 bytes_per_cycle=3.97619/s bytes_per_second=8.332G/s items_per_second=134.044M/s __llvm_libc::memmove,memmove Google S
BM_Memmove/7/0_median       5.40 ns         5.40 ns           10 bytes_per_cycle=1.79695/s bytes_per_second=3.76546G/s items_per_second=185.211M/s __llvm_libc::memmove,memmove Google U
BM_Memmove/8/0_median       5.62 ns         5.62 ns           10 bytes_per_cycle=3.18747/s bytes_per_second=6.67927G/s items_per_second=177.983M/s __llvm_libc::memmove,memmove Google W
BM_Memmove/9/0_median        101 ns          101 ns           10 bytes_per_cycle=9.77359/s bytes_per_second=20.4803G/s items_per_second=9.9333M/s __llvm_libc::memmove,uniform 384 to 4096
```
After
```
BM_Memmove/0/0_median       3.57 ns         3.57 ns           10 bytes_per_cycle=1.71375/s bytes_per_second=3.59112G/s items_per_second=280.411M/s __llvm_libc::memmove,memmove Google A
BM_Memmove/1/0_median       4.52 ns         4.52 ns           10 bytes_per_cycle=4.47557/s bytes_per_second=9.37843G/s items_per_second=221.427M/s __llvm_libc::memmove,memmove Google B
BM_Memmove/2/0_median       5.70 ns         5.70 ns           10 bytes_per_cycle=7.37396/s bytes_per_second=15.4519G/s items_per_second=175.399M/s __llvm_libc::memmove,memmove Google D
BM_Memmove/3/0_median       4.47 ns         4.47 ns           10 bytes_per_cycle=3.4148/s bytes_per_second=7.15563G/s items_per_second=223.743M/s __llvm_libc::memmove,memmove Google L
BM_Memmove/4/0_median       4.53 ns         4.53 ns           10 bytes_per_cycle=2.86071/s bytes_per_second=5.99454G/s items_per_second=220.69M/s __llvm_libc::memmove,memmove Google M
BM_Memmove/5/0_median       4.19 ns         4.19 ns           10 bytes_per_cycle=2.5484/s bytes_per_second=5.3401G/s items_per_second=238.924M/s __llvm_libc::memmove,memmove Google Q
BM_Memmove/6/0_median       5.02 ns         5.02 ns           10 bytes_per_cycle=5.94164/s bytes_per_second=12.4505G/s items_per_second=199.14M/s __llvm_libc::memmove,memmove Google S
BM_Memmove/7/0_median       4.03 ns         4.03 ns           10 bytes_per_cycle=2.47028/s bytes_per_second=5.17641G/s items_per_second=247.906M/s __llvm_libc::memmove,memmove Google U
BM_Memmove/8/0_median       4.70 ns         4.70 ns           10 bytes_per_cycle=3.84975/s bytes_per_second=8.06706G/s items_per_second=212.72M/s __llvm_libc::memmove,memmove Google W
BM_Memmove/9/0_median       90.7 ns         90.7 ns           10 bytes_per_cycle=10.8681/s bytes_per_second=22.7739G/s items_per_second=11.02M/s __llvm_libc::memmove,uniform 384 to 4096
```

Reviewed By: courbet

Differential Revision: https://reviews.llvm.org/D152811
2023-06-14 08:29:15 +00:00
Tue Ly
1557256ab0 [libc] Add Int<> type and fix (U)Int<128> compatibility issues.
Add Int<> and Int128 types to replace the usage of __int128_t in math
functions.  Clean up to make sure that (U)Int128 and __(u)int128_t are
interchangeable in the code base.

Reviewed By: sivachandra, mikhail.ramalho

Differential Revision: https://reviews.llvm.org/D152459
2023-06-13 09:40:48 -04:00
Joseph Huber
746e72910f [libc] Fix floating point test failing to build on the GPU
A patch enabled this test which uses that `add_fp_unittest`.
Unfortunately we do not support these on the GPU because it attempts to
link in the floating point utils which are not built supporting
hermetic tests. This was attempted to be fixed in D151123 but that had
to be reverted. For now disable these so the tests pass.

Reviewed By: tra

Differential Revision: https://reviews.llvm.org/D152742
2023-06-12 15:06:33 -05:00
Michael Jones
d3074f16a6 [libc] Add qsort_r
This patch adds the reentrent qsort entrypoint, qsort_r. This is done by
extending the qsort functionality and moving it to a shared utility
header. For this reason the qsort_r tests focus mostly on the places
where it differs from qsort, since they share the same sorting code.

Reviewed By: sivachandra, lntue

Differential Revision: https://reviews.llvm.org/D152467
2023-06-12 11:12:17 -07:00
Guillaume Chatelet
5e32765c15 [libc] Improve memcmp latency and codegen
This is based on ideas from @nafi to:
 - use a branchless version of 'cmp' for 'uint32_t',
 - completely resolve the lexicographic comparison through vector
   operations when wide types are available. We also get rid of byte
   reloads and serializing '__builtin_ctzll'.

I did not include the suggestion to replace comparisons of 'uint16_t'
with two 'uint8_t' as it did not seem to help the codegen. This can
be revisited in sub-sequent patches.

The code been rewritten to reduce nested function calls, making the
job of the inliner easier and preventing harmful code duplication.

Reviewed By: nafi3000

Differential Revision: https://reviews.llvm.org/D148717
2023-06-12 13:47:16 +00:00
Tue Ly
a982431295 [libc] Add platform independent floating point rounding mode checks.
Many math functions need to check for floating point rounding modes to
return correct values.  Currently most of them use the internal implementation
of `fegetround`, which is platform-dependent and blocking math functions to be
enabled on platforms with unimplemented `fegetround`.  In this change, we add
platform independent rounding mode checks and switching math functions to use
them instead. https://github.com/llvm/llvm-project/issues/63016

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D152280
2023-06-12 09:36:41 -04:00
Guillaume Chatelet
1ec995cc1c Revert D148717 "[libc] Improve memcmp latency and codegen"
This broke aarch64 debug buildbot https://lab.llvm.org/buildbot/#/builders/223/builds/21703
This reverts commit bd4f978754.
2023-06-12 08:32:00 +00:00
Guillaume Chatelet
bd4f978754 [libc] Improve memcmp latency and codegen
This is based on ideas from @nafi to:
 - use a branchless version of 'cmp' for 'uint32_t',
 - completely resolve the lexicographic comparison through vector
   operations when wide types are available. We also get rid of byte
   reloads and serializing '__builtin_ctzll'.

I did not include the suggestion to replace comparisons of 'uint16_t'
with two 'uint8_t' as it did not seem to help the codegen. This can
be revisited in sub-sequent patches.

The code been rewritten to reduce nested function calls, making the
job of the inliner easier and preventing harmful code duplication.

Reviewed By: nafi3000

Differential Revision: https://reviews.llvm.org/D148717
2023-06-12 07:56:23 +00:00
Guillaume Chatelet
8e44b849da [libc][NFC] Introduce a Location object for consistent failure logging
This is just an implementation detail.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D152532
2023-06-10 06:58:15 +00:00
Guillaume Chatelet
0fd0b74289 [libc][NFC] Clean up matchers namespace
This is a follow up to https://reviews.llvm.org/D152503

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D152533
2023-06-10 06:55:16 +00:00
Tue Ly
37458f6693 [libc][math] Move str method from FPBits class to testing utils.
str method of FPBits class is only used for pretty printing its objects
in tests.  It brings cpp::string dependency to FPBits class, which is not ideal
for embedded use case.  We move str method to a free function in test utils and
remove this dependency of FPBits class.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D152607
2023-06-10 02:50:58 -04:00
Joseph Huber
168fa31816 [libc] Fix some tests on NVPTX due to insufficient stack size
A few of these tests were disabled due to failing on NVPTX. After
looking into it the vast majority of these cases were due to
insufficient stack memory. This can be worked around by increasing the
stack size in the loader or by reducing the memory usage in the case of
large string constants.

Reviewed By: tra

Differential Revision: https://reviews.llvm.org/D152583
2023-06-09 16:42:14 -05:00
Guillaume Chatelet
fd2c74c8ed [libc][NFC] Simplify LibcTest and trim down string allocations
This is a bit of cleanup before working on logging via stream operator (i.e., `EXPECT_XXX() << ...`).

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D152503
2023-06-09 09:36:18 +00:00
Joseph Huber
63710fd529 [libc] Disable uint test on NVPTX GPUs
This test started failing on Nvidia, we need to disable it to keep the
bot green until we can investigate the root cause.

Differential Revision: https://reviews.llvm.org/D152481
2023-06-08 17:54:27 -05:00
Michael Jones
5df182f121 [libc] disable printf Lf tests for float128 plats
The results for the %Lf tests were calculated on 80 bit long double
systems, meaning the results are not necessarily accurate for float128
systems. In future these will be fixed, but for the moment I'm just
turning them off.

Differential Revision: https://reviews.llvm.org/D152471
2023-06-08 14:35:51 -07:00
Michael Jones
688b9730d1 [libc] add options to printf decimal floats
This patch adds three options for printf decimal long doubles, and these
can also apply to doubles.

1. Use a giant table which is fast and accurate, but takes up ~5MB).
2. Use dyadic floats for approximations, which only gives ~50 digits of
   accuracy but is very fast.
3. Use large integers for approximations, which is accurate but very
   slow.

Reviewed By: sivachandra, lntue

Differential Revision: https://reviews.llvm.org/D150399
2023-06-08 14:23:15 -07:00
Tue Ly
b95ed8b6d9 [libc] Remove operator T from cpp::expected.
The libc's equivalent of std::expected has a non-standard and
non-explicit operator T - https://github.com/llvm/llvm-project/issues/62738

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D152270
2023-06-06 13:57:44 -04:00
Joseph Huber
e6c401b5e8 [libc] Add initial support for 'puts' and 'fputs' to the GPU
This patch adds the initial support required to support basic priting in
`stdio.h` via `puts` and `fputs`. This is done using the existing LLVM C
library `File` API. In this sense we can think of the RPC interface as
our system call to dump the character string to the file. We carry a
`uintptr_t` reference as our native "file descriptor" as it will be used
as an opaque reference to the host's version once functions like
`fopen` are supported.

For some unknown reason the declaration of the `StdIn` variable causes
both the AMDGPU and NVPTX backends to crash if I use the `READ` flag.
This is not used currently as we only support output now, but it needs
to be fixed

Reviewed By: sivachandra, lntue

Differential Revision: https://reviews.llvm.org/D151282
2023-06-05 17:56:55 -05:00
Joseph Huber
a621308881 [libc] Implement basic malloc and free support on the GPU
This patch adds support for the `malloc` and `free` functions. These
currently aren't implemented in-tree so we first add the interface
filies.

This patch provides the most basic support for a true `malloc` and
`free` by using the RPC interface. This is functional, but in the future
we will want to implement a more intelligent system and primarily use
the RPC interface more as a `brk()` or `sbrk()` interface only called
when absolutely necessary. We will need to design an intelligent
allocator in the future.

The semantics of these memory allocations will need to be checked. I am
somewhat iffy on the details. I've heard that HSA can allocate
asynchronously which seems to work with my tests at least. CUDA uses an
implicit synchronization scheme so we need to use an explicitly separate
stream from the one launching the kernel or the default stream. I will
need to test the NVPTX case.

I would appreciate if anyone more experienced with the implementation details
here could chime in for the HSA and CUDA cases.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D151735
2023-06-05 17:56:53 -05:00