[PATCH 3/7] riscv: thead: Add support for XTheadBa and XTheadBs ISA extensions

[Christoph Muellner <christoph.muellner@vrull.eu>]

From: Christoph Müllner <christoph.muellner@vrull.eu>

This patch adds support for the following T-Head vendor extensions:
* XTheadBa
* XTheadBs

Both extensions provide just one instruction, that has a counterpart
in the similar named Bitmanip ISA extension.

gcc/ChangeLog:

	* config/riscv/riscv.cc (riscv_rtx_costs): Adjust for th.tst.
	* config/riscv/riscv.md: Include thead.md.
	* config/riscv/thead.md: New file.

gcc/testsuite/ChangeLog:

	* gcc.target/riscv/xtheadba-addsl-64.c: New test.
	* gcc.target/riscv/xtheadba-addsl.c: New test.
	* gcc.target/riscv/xtheadbs-tst.c: New test.

Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>
---
 gcc/config/riscv/riscv.cc                     |  4 +-
 gcc/config/riscv/riscv.md                     |  1 +
 gcc/config/riscv/thead.md                     | 38 +++++++++++++++++++
 .../gcc.target/riscv/xtheadba-addsl-64.c      | 18 +++++++++
 .../gcc.target/riscv/xtheadba-addsl.c         | 20 ++++++++++
 gcc/testsuite/gcc.target/riscv/xtheadbs-tst.c | 12 ++++++
 6 files changed, 91 insertions(+), 2 deletions(-)
 create mode 100644 gcc/config/riscv/thead.md
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadba-addsl-64.c
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadba-addsl.c
 create mode 100644 gcc/testsuite/gcc.target/riscv/xtheadbs-tst.c

diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index 02a01ca0b7c..decade0fedd 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -2369,8 +2369,8 @@ riscv_rtx_costs (rtx x, machine_mode mode, int outer_code, int opno ATTRIBUTE_UN
 	  *total = COSTS_N_INSNS (SINGLE_SHIFT_COST);
 	  return true;
 	}
-      /* bext pattern for zbs.  */
-      if (TARGET_ZBS && outer_code == SET
+      /* bit extraction pattern (zbs:bext, xtheadbs:tst).  */
+      if ((TARGET_ZBS || TARGET_XTHEADBS) && outer_code == SET
 	  && GET_CODE (XEXP (x, 1)) == CONST_INT
 	  && INTVAL (XEXP (x, 1)) == 1)
 	{
diff --git a/gcc/config/riscv/riscv.md b/gcc/config/riscv/riscv.md
index 798f7370a08..a9254df7820 100644
--- a/gcc/config/riscv/riscv.md
+++ b/gcc/config/riscv/riscv.md
@@ -3009,3 +3009,4 @@ (define_insn "riscv_prefetchi_<mode>"
 (include "generic.md")
 (include "sifive-7.md")
 (include "vector.md")
+(include "thead.md")
diff --git a/gcc/config/riscv/thead.md b/gcc/config/riscv/thead.md
new file mode 100644
index 00000000000..676d10b71d7
--- /dev/null
+++ b/gcc/config/riscv/thead.md
@@ -0,0 +1,38 @@
+;; Machine description for T-Head vendor extensions
+;; Copyright (C) 2021-2022 Free Software Foundation, Inc.
+
+;; This file is part of GCC.
+
+;; GCC is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation; either version 3, or (at your option)
+;; any later version.
+
+;; GCC is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GCC; see the file COPYING3.  If not see
+;; <http://www.gnu.org/licenses/>.
+
+(define_insn "*th_addsl"
+  [(set (match_operand:X 0 "register_operand" "=r")
+	(plus:X (ashift:X (match_operand:X 1 "register_operand" "r")
+			  (match_operand:QI 2 "immediate_operand" "I"))
+		(match_operand:X 3 "register_operand" "r")))]
+  "TARGET_XTHEADBA
+   && (INTVAL (operands[2]) >= 0) && (INTVAL (operands[2]) <= 3)"
+  "th.addsl\t%0,%1,%3,%2"
+  [(set_attr "type" "bitmanip")
+   (set_attr "mode" "<X:MODE>")])
+
+(define_insn "*th_tst"
+  [(set (match_operand:X 0 "register_operand" "=r")
+	(zero_extract:X (match_operand:X 1 "register_operand" "r")
+			(const_int 1)
+			(match_operand 2 "immediate_operand" "i")))]
+  "TARGET_XTHEADBS"
+  "th.tst\t%0,%1,%2"
+  [(set_attr "type" "bitmanip")])
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadba-addsl-64.c b/gcc/testsuite/gcc.target/riscv/xtheadba-addsl-64.c
new file mode 100644
index 00000000000..7f47929967a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadba-addsl-64.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadba -mabi=lp64" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" } } */
+
+/* RV64 only.  */
+int foos(short *x, int n){
+  return x[n];
+}
+int fooi(int *x, int n){
+  return x[n];
+}
+int fooll(long long *x, int n){
+  return x[n];
+}
+
+/* { dg-final { scan-assembler-times "th.addsl\[ \t\]*a\[0-9\]+,a\[0-9\]+,a\[0-9\]+,1" 1 } } */
+/* { dg-final { scan-assembler-times "th.addsl\[ \t\]*a\[0-9\]+,a\[0-9\]+,a\[0-9\]+,2" 1 } } */
+/* { dg-final { scan-assembler-times "th.addsl\[ \t\]*a\[0-9\]+,a\[0-9\]+,a\[0-9\]+,3" 1 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadba-addsl.c b/gcc/testsuite/gcc.target/riscv/xtheadba-addsl.c
new file mode 100644
index 00000000000..d739f715430
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadba-addsl.c
@@ -0,0 +1,20 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadba -mabi=lp64" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" } } */
+
+long test_1(long a, long b)
+{
+  return a + (b << 1);
+}
+long test_2(long a, long b)
+{
+  return a + (b << 2);
+}
+long test_3(long a, long b)
+{
+  return a + (b << 3);
+}
+
+/* { dg-final { scan-assembler-times "th.addsl\[ \t\]*a\[0-9\]+,a\[0-9\]+,a\[0-9\]+,1" 1 } } */
+/* { dg-final { scan-assembler-times "th.addsl\[ \t\]*a\[0-9\]+,a\[0-9\]+,a\[0-9\]+,2" 1 } } */
+/* { dg-final { scan-assembler-times "th.addsl\[ \t\]*a\[0-9\]+,a\[0-9\]+,a\[0-9\]+,3" 1 } } */
diff --git a/gcc/testsuite/gcc.target/riscv/xtheadbs-tst.c b/gcc/testsuite/gcc.target/riscv/xtheadbs-tst.c
new file mode 100644
index 00000000000..f4887bde535
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/xtheadbs-tst.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-march=rv64gc_xtheadbs -mabi=lp64" } */
+/* { dg-skip-if "" { *-*-* } { "-O0" } } */
+
+long
+foo1 (long i)
+{
+  return 1L & (i >> 20);
+}
+
+/* { dg-final { scan-assembler-times "th.tst\t" 1 } } */
+/* { dg-final { scan-assembler-not "andi" } } */
-- 
2.38.1