These build-ins are used internally for the
TARGET_ATOMIC_ASSIGN_EXPAND_FENV expansion (and therefore can not be
removed):
/* Implement TARGET_ATOMIC_ASSIGN_EXPAND_FENV. */
void
riscv_atomic_assign_expand_fenv (tree *hold, tree *clear, tree *update)
{
if (!(TARGET_HARD_FLOAT || TARGET_ZFINX))
return;
tree frflags = GET_BUILTIN_DECL (CODE_FOR_riscv_frflags);
tree fsflags = GET_BUILTIN_DECL (CODE_FOR_riscv_fsflags);
tree old_flags = create_tmp_var_raw (RISCV_ATYPE_USI);
*hold = build4 (TARGET_EXPR, RISCV_ATYPE_USI, old_flags,
build_call_expr (frflags, 0), NULL_TREE, NULL_TREE);
*clear = build_call_expr (fsflags, 1, old_flags);
*update = NULL_TREE;
}
On Wed, 29 Nov 2023 at 20:58, Christoph Müllner
<christoph.muell...@vrull.eu> wrote:
>
> On Wed, Nov 29, 2023 at 8:24 PM Patrick O'Neill <patr...@rivosinc.com> wrote:
> >
> > Hi Christoph,
> >
> > The precommit-ci is seeing a large number of ICE segmentation faults as a
> > result of this patch:
> > https://github.com/ewlu/gcc-precommit-ci/issues/796#issuecomment-1831853523
> >
> > The failures aren't in riscv.exp testsuite files so that's likely why you
> > didn't run into them in your testing.
>
> Oh, I see.
> Then keeping things like they are is probably the best idea.
> Sorry for the noise!
>
> BR
> Christoph
>
> >
> > Debug log:
> >
> > /home/runner/work/gcc-precommit-ci/gcc-precommit-ci/riscv-gnu-toolchain/gcc/gcc/testsuite/gcc.dg/c11-atomic-2.c:110:3:
> > internal compiler error: Segmentation fault
> > 0x133afb3 crash_signal
> > ../../../gcc/gcc/toplev.cc:316
> > 0x1678d1f contains_struct_check(tree_node*, tree_node_structure_enum, char
> > const*, int, char const*)
> > ../../../gcc/gcc/tree.h:3747
> > 0x1678d1f build_call_expr_loc_array(unsigned int, tree_node*, int,
> > tree_node**)
> > ../../../gcc/gcc/tree.cc:10815
> > 0x1679043 build_call_expr(tree_node*, int, ...)
> > ../../../gcc/gcc/tree.cc:10865
> > 0x17f816e riscv_atomic_assign_expand_fenv(tree_node**, tree_node**,
> > tree_node**)
> > ../../../gcc/gcc/config/riscv/riscv-builtins.cc:420
> > 0xc5209b build_atomic_assign
> > ../../../gcc/gcc/c/c-typeck.cc:4289
> > 0xc60a47 build_modify_expr(unsigned int, tree_node*, tree_node*, tree_code,
> > unsigned int, tree_node*, tree_node*)
> > ../../../gcc/gcc/c/c-typeck.cc:6406
> > 0xc85a61 c_parser_expr_no_commas
> > ../../../gcc/gcc/c/c-parser.cc:9112
> > 0xc85db1 c_parser_expression
> > ../../../gcc/gcc/c/c-parser.cc:12725
> > 0xc862bb c_parser_expression_conv
> > ../../../gcc/gcc/c/c-parser.cc:12765
> > 0xca3607 c_parser_statement_after_labels
> > ../../../gcc/gcc/c/c-parser.cc:7755
> > 0xc9f27e c_parser_compound_statement_nostart
> > ../../../gcc/gcc/c/c-parser.cc:7242
> > 0xc9f804 c_parser_compound_statement
> > ../../../gcc/gcc/c/c-parser.cc:6527
> > 0xca359c c_parser_statement_after_labels
> > ../../../gcc/gcc/c/c-parser.cc:7590
> > 0xca5713 c_parser_statement
> > ../../../gcc/gcc/c/c-parser.cc:7561
> > 0xca5713 c_parser_c99_block_statement
> > ../../../gcc/gcc/c/c-parser.cc:7820
> > 0xca6a2c c_parser_do_statement
> > ../../../gcc/gcc/c/c-parser.cc:8194
> > 0xca3d51 c_parser_statement_after_labels
> > ../../../gcc/gcc/c/c-parser.cc:7605
> > 0xc9f27e c_parser_compound_statement_nostart
> > ../../../gcc/gcc/c/c-parser.cc:7242
> > 0xc9f804 c_parser_compound_statement
> > ../../../gcc/gcc/c/c-parser.cc:6527
> > Please submit a full bug report, with preprocessed source (by using
> > -freport-bug).
> > Please include the complete backtrace with any bug report.
> > See <https://gcc.gnu.org/bugs/> for instructions.
> > compiler exited with status 1
> > FAIL: gcc.dg/c11-atomic-2.c (internal compiler error: Segmentation fault)
> >
> > Let me know if you need any additional info/investigation from me.
> >
> > Thanks,
> > Patrick
> >
> > On 11/29/23 03:49, Christoph Muellner wrote:
> >
> > From: Christoph Müllner <christoph.muell...@vrull.eu>
> >
> > We have two builtins which are undocumented and have no known users.
> > Further, they don't exist in LLVM (so are no portable).
> > This means they are in an unclear state of being supported or not.
> > Let's remove them get them out of this undecided state.
> >
> > A discussion about making these builtins available in all
> > compilers was held many years ago with the decision to
> > not document them in the RISC-V C API documentation:
> > https://github.com/riscv-non-isa/riscv-c-api-doc/pull/3
> >
> > This is an RFC patch as this breaks existing code that uses
> > these builtins, even if we don't know if such code exists.
> >
> > An alternative to this patch would be to document them
> > in gcc/doc/extend.texi (like has been done with __builtin_riscv_pause)
> > and put them into a supported state.
> >
> > This patch removes two tests for these builtins.
> > A test of this patch did not trigger any regressions in riscv.exp.
> >
> > Signed-off-by: Christoph Müllner <christoph.muell...@vrull.eu>
> >
> > gcc/ChangeLog:
> >
> > * config/riscv/riscv-builtins.cc: Remove the builtins
> > __builtin_riscv_frflags and __builtin_riscv_fsflags.
> >
> > gcc/testsuite/ChangeLog:
> >
> > * g++.target/riscv/frflags.C: Removed.
> > * gcc.target/riscv/fsflags.c: Removed.
> > ---
> > gcc/config/riscv/riscv-builtins.cc | 2 --
> > gcc/testsuite/g++.target/riscv/frflags.C | 7 -------
> > gcc/testsuite/gcc.target/riscv/fsflags.c | 16 ----------------
> > 3 files changed, 25 deletions(-)
> > delete mode 100644 gcc/testsuite/g++.target/riscv/frflags.C
> > delete mode 100644 gcc/testsuite/gcc.target/riscv/fsflags.c
> >
> > diff --git a/gcc/config/riscv/riscv-builtins.cc
> > b/gcc/config/riscv/riscv-builtins.cc
> > index fc3976f3ba1..1655492b246 100644
> > --- a/gcc/config/riscv/riscv-builtins.cc
> > +++ b/gcc/config/riscv/riscv-builtins.cc
> > @@ -188,8 +188,6 @@ static const struct riscv_builtin_description
> > riscv_builtins[] = {
> > #include "riscv-scalar-crypto.def"
> > #include "corev.def"
> >
> > - DIRECT_BUILTIN (frflags, RISCV_USI_FTYPE, hard_float),
> > - DIRECT_NO_TARGET_BUILTIN (fsflags, RISCV_VOID_FTYPE_USI, hard_float),
> > RISCV_BUILTIN (pause, "pause", RISCV_BUILTIN_DIRECT_NO_TARGET,
> > RISCV_VOID_FTYPE, hint_pause),
> > };
> >
> > diff --git a/gcc/testsuite/g++.target/riscv/frflags.C
> > b/gcc/testsuite/g++.target/riscv/frflags.C
> > deleted file mode 100644
> > index 6353044dcf7..00000000000
> > --- a/gcc/testsuite/g++.target/riscv/frflags.C
> > +++ /dev/null
> > @@ -1,7 +0,0 @@
> > -/* { dg-options "-O2 -march=rv32if -mabi=ilp32f" } */
> > -/* { dg-do compile } */
> > -
> > -int f()
> > -{
> > - return __builtin_riscv_frflags();
> > -}
> > diff --git a/gcc/testsuite/gcc.target/riscv/fsflags.c
> > b/gcc/testsuite/gcc.target/riscv/fsflags.c
> > deleted file mode 100644
> > index 74a97b8a7c7..00000000000
> > --- a/gcc/testsuite/gcc.target/riscv/fsflags.c
> > +++ /dev/null
> > @@ -1,16 +0,0 @@
> > -/* Verify that fsflags is using the correct register or immediate. */
> > -/* { dg-do compile } */
> > -/* { dg-require-effective-target hard_float } */
> > -/* { dg-options "-O" } */
> > -
> > -void foo1 (int a)
> > -{
> > - __builtin_riscv_fsflags(a);
> > -}
> > -void foo2 ()
> > -{
> > - __builtin_riscv_fsflags(4);
> > -}
> > -
> > -/* { dg-final { scan-assembler-times "fsflags\t" 1 } } */
> > -/* { dg-final { scan-assembler-times "fsflagsi\t" 1 } } */
