[PATCH] riscv: allow zero in zacas subword atomic cas

gcc:
	PR target/120995
	* config/riscv/sync.md (zacas_atomic_cas_value_strong<mode>):
	Allow op3 to be zero.

gcc/testsuite:
	PR target/120995
	* gcc.target/riscv/amo/zabha-zacas-atomic-cas.c: New test.

(cherry picked from commit 3fd638a9e5497dfdf00f1783d6e704af03fb44b0)

diff --git a/gcc/config/riscv/sync.md b/gcc/config/riscv/sync.md
index 726800a9662315ef8f1c8c9b5d0e34523a6cf976..22acf0850f676dfee44a2f857f37284dac346a30 100644 (file)
--- a/gcc/config/riscv/sync.md
+++ b/gcc/config/riscv/sync.md
@@ -628,7 +628,7 @@
        (match_operand:SHORT 1 "memory_operand" "+A"))                          ;; memory
    (set (match_dup 1)
        (unspec_volatile:SHORT [(match_operand:SHORT 2 "register_operand" "0")  ;; expected_val
-                               (match_operand:SHORT 3 "register_operand" "rJ") ;; desired_val
+                               (match_operand:SHORT 3 "reg_or_0_operand" "rJ") ;; desired_val
                                (match_operand:SI 4 "const_int_operand")        ;; mod_s
                                (match_operand:SI 5 "const_int_operand")]       ;; mod_f
         UNSPEC_COMPARE_AND_SWAP))]

diff --git a/gcc/testsuite/gcc.target/riscv/amo/zabha-zacas-atomic-cas.c b/gcc/testsuite/gcc.target/riscv/amo/zabha-zacas-atomic-cas.c
new file mode 100644 (file)
index 0000000..d3d84fd
--- /dev/null
+++ b/gcc/testsuite/gcc.target/riscv/amo/zabha-zacas-atomic-cas.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+/* PR target/120995 ICE unrecognized subword atomic cas */
+/* { dg-options "-O" } */
+/* { dg-add-options riscv_zacas } */
+/* { dg-add-options riscv_zabha } */
+
+_Bool b;
+void atomic_bool_cmpxchg()
+{
+  __sync_bool_compare_and_swap(&b, 1, 0);
+}