By default the RISC-V target doesn't have the atomics standard extension
enabled. The first RUN line in `clang/test/CodeGen/atomic_ops.c` didn't
specify a target triple, which meant that on RISC-V Linux hosts it would
target RISC-V, but because it used clang cc1 we didn't get the toolchain
driver functionality to automatically turn on the extensions implied by
the target triple (riscv64-linux includes atomics). This would cause the
test to fail on RISC-V hosts.
This patch changes the test to have RUN lines for two explicit targets,
one with native atomics and one without. To work around FileCheck
limitations and more accurately match the output, some tests now have
separate prefixes for the two cases.
Reviewers: jyknight, eli.friedman, lenary, efriedma
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D74847
Atomic compound expressions try to use atomicrmw if possible, but this
path doesn't set the Result variable, leaving it to crash in later code
if anything ever tries to use the result of the expression. This fixes
that issue by recalculating the new value based on the old one
atomically loaded.
Not all targets generate 'store atomic' instructions for
'_Atomic(_Complex int)'. Some targets use the __atomic_store builtin instead.
This commit makes the test accept either one.
llvm-svn: 229676
Bools are a little tricky, they are i8 in memory and must be coerced
back to i1 before further operations can be performed on them.
This fixes PR22577.
llvm-svn: 229204
- Generate atomicrmw operations in most of the cases when it's sensible to do
so.
- Don't crash in several common cases (and hopefully don't crash in more of
them).
- Add some better tests.
We now generate significantly better code for things like:
_Atomic(int) x;
...
x++;
On MIPS, this now generates a 4-instruction ll/sc loop, where previously it
generated about 30 instructions in two nested loops. On x86-64, we generate a
single lock incl, instead of a lock cmpxchgl loop (one instruction instead of
ten).
llvm-svn: 176420
- Add atomic-to/from-nonatomic cast types
- Emit atomic operations for arithmetic on atomic types
- Emit non-atomic stores for initialisation of atomic types, but atomic stores and loads for every other store / load
- Add a __atomic_init() intrinsic which does a non-atomic store to an _Atomic() type. This is needed for the corresponding C11 stdatomic.h function.
- Enables the relevant __has_feature() checks. The feature isn't 100% complete yet, but it's done enough that we want people testing it.
Still to do:
- Make the arithmetic operations on atomic types (e.g. Atomic(int) foo = 1; foo++;) use the correct LLVM intrinsic if one exists, not a loop with a cmpxchg.
- Add a signal fence builtin
- Properly set the fenv state in atomic operations on floating point values
- Correctly handle things like _Atomic(_Complex double) which are too large for an atomic cmpxchg on some platforms (this requires working out what 'correctly' means in this context)
- Fix the many remaining corner cases
llvm-svn: 148242
Luís Marques