RISC-V: Add support for Zabha extension

The Zabha extension adds support for subword Zaamo ops.

Extension: https://github.com/riscv/riscv-zabha.git
Ratification: https://jira.riscv.org/browse/RVS-1685

gcc/ChangeLog:

	* common/config/riscv/riscv-common.cc
	(riscv_subset_list::to_string): Skip zabha when not supported by
	the assembler.
	* config.in: Regenerate.
	* config/riscv/arch-canonicalize: Make zabha imply zaamo.
	* config/riscv/iterators.md (amobh): Add iterator for amo
	byte/halfword.
	* config/riscv/riscv.opt: Add zabha.
	* config/riscv/sync.md (atomic_<atomic_optab><mode>): Add
	subword atomic op pattern.
	(zabha_atomic_fetch_<atomic_optab><mode>): Add subword
	atomic_fetch op pattern.
	(lrsc_atomic_fetch_<atomic_optab><mode>): Prefer zabha over lrsc
	for subword atomic ops.
	(zabha_atomic_exchange<mode>): Add subword atomic exchange
	pattern.
	(lrsc_atomic_exchange<mode>): Prefer zabha over lrsc for subword
	atomic exchange ops.
	* configure: Regenerate.
	* configure.ac: Add zabha assembler check.
	* doc/sourcebuild.texi: Add zabha documentation.

gcc/testsuite/ChangeLog:

	* lib/target-supports.exp: Add zabha testsuite infra support.
	* gcc.target/riscv/amo/inline-atomics-1.c: Remove zabha to continue to
	test the lr/sc subword patterns.
	* gcc.target/riscv/amo/inline-atomics-2.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-rvwmo-subword-amo-add-char-acq-rel.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-rvwmo-subword-amo-add-char-acquire.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-rvwmo-subword-amo-add-char-relaxed.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-rvwmo-subword-amo-add-char-release.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-rvwmo-subword-amo-add-char-seq-cst.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-ztso-subword-amo-add-char-acq-rel.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-ztso-subword-amo-add-char-acquire.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-ztso-subword-amo-add-char-relaxed.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-ztso-subword-amo-add-char-release.c: Ditto.
	* gcc.target/riscv/amo/zalrsc-ztso-subword-amo-add-char-seq-cst.c: Ditto.
	* gcc.target/riscv/amo/zabha-all-amo-ops-char-run.c: New test.
	* gcc.target/riscv/amo/zabha-all-amo-ops-short-run.c: New test.
	* gcc.target/riscv/amo/zabha-rvwmo-all-amo-ops-char.c: New test.
	* gcc.target/riscv/amo/zabha-rvwmo-all-amo-ops-short.c: New test.
	* gcc.target/riscv/amo/zabha-rvwmo-amo-add-char.c: New test.
	* gcc.target/riscv/amo/zabha-rvwmo-amo-add-short.c: New test.
	* gcc.target/riscv/amo/zabha-ztso-amo-add-char.c: New test.
	* gcc.target/riscv/amo/zabha-ztso-amo-add-short.c: New test.

Co-Authored-By: Patrick O'Neill <patrick@rivosinc.com>
Signed-Off-By: Gianluca Guida <gianluca@rivosinc.com>
Tested-by: Andrea Parri <andrea@rivosinc.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/gcc/common/config/riscv/riscv-common.cc b/gcc/common/config/riscv/riscv-common.cc
index 410e673..16bdb3f 100644
--- a/gcc/common/config/riscv/riscv-common.cc
+++ b/gcc/common/config/riscv/riscv-common.cc
@@ -82,6 +82,8 @@ static const riscv_implied_info_t riscv_implied_info[] =
   {"a", "zaamo"},
   {"a", "zalrsc"},
 
+  {"zabha", "zaamo"},
+
   {"zdinx", "zfinx"},
   {"zfinx", "zicsr"},
   {"zdinx", "zicsr"},
@@ -260,6 +262,7 @@ static const struct riscv_ext_version riscv_ext_version_table[] =
   {"zawrs", ISA_SPEC_CLASS_NONE, 1, 0},
   {"zaamo", ISA_SPEC_CLASS_NONE, 1, 0},
   {"zalrsc", ISA_SPEC_CLASS_NONE, 1, 0},
+  {"zabha", ISA_SPEC_CLASS_NONE, 1, 0},
 
   {"zba", ISA_SPEC_CLASS_NONE, 1, 0},
   {"zbb", ISA_SPEC_CLASS_NONE, 1, 0},
@@ -918,6 +921,7 @@ riscv_subset_list::to_string (bool version_p) const
 
   bool skip_zifencei = false;
   bool skip_zaamo_zalrsc = false;
+  bool skip_zabha = false;
   bool skip_zicsr = false;
   bool i2p0 = false;
 
@@ -949,6 +953,10 @@ riscv_subset_list::to_string (bool version_p) const
   /* Skip since binutils 2.42 and earlier don't recognize zaamo/zalrsc.  */
   skip_zaamo_zalrsc = true;
 #endif
+#ifndef HAVE_AS_MARCH_ZABHA
+  /* Skip since binutils 2.42 and earlier don't recognize zabha.  */
+  skip_zabha = true;
+#endif
 
   for (subset = m_head; subset != NULL; subset = subset->next)
     {
@@ -966,6 +974,9 @@ riscv_subset_list::to_string (bool version_p) const
       if (skip_zaamo_zalrsc && subset->name == "zalrsc")
 	continue;
 
+      if (skip_zabha && subset->name == "zabha")
+	continue;
+
       /* For !version_p, we only separate extension with underline for
 	 multi-letter extension.  */
       if (!first &&
@@ -1638,6 +1649,7 @@ static const riscv_ext_flag_table_t riscv_ext_flag_table[] =
   {"zawrs",   &gcc_options::x_riscv_za_subext, MASK_ZAWRS},
   {"zaamo",   &gcc_options::x_riscv_za_subext, MASK_ZAAMO},
   {"zalrsc",  &gcc_options::x_riscv_za_subext, MASK_ZALRSC},
+  {"zabha",   &gcc_options::x_riscv_za_subext, MASK_ZABHA},
 
   {"zba",    &gcc_options::x_riscv_zb_subext, MASK_ZBA},
   {"zbb",    &gcc_options::x_riscv_zb_subext, MASK_ZBB},