[committed][nvptx] Add shf.{l,r}.wrap insn

[Tom de Vries via Gcc-patches]

On 2/23/22 12:40, Tom de Vries wrote:

Hi,

Ptx contains funnel shift operations shf.l.wrap and shf.r.wrap that can be
used to implement 32-bit left or right rotate.

Add define_insns rotlsi3 and rotrsi3.

Currently testing.

And committed.

Thanks,
- Tom

[nvptx] Add shf.{l,r}.wrap insn

gcc/ChangeLog:

2022-02-23  Tom de Vries  <tdevr...@suse.de>

        * config/nvptx/nvptx.md (define_insn "rotlsi3", define_insn
        "rotrsi3"): New define_insn.

gcc/testsuite/ChangeLog:

2022-02-23  Tom de Vries  <tdevr...@suse.de>

        * gcc.target/nvptx/rotate-run.c: New test.
        * gcc.target/nvptx/rotate.c: New test.

---
  gcc/config/nvptx/nvptx.md                   | 16 ++++++++++++++++
  gcc/testsuite/gcc.target/nvptx/rotate-run.c | 23 +++++++++++++++++++++++
  gcc/testsuite/gcc.target/nvptx/rotate.c     | 20 ++++++++++++++++++++
  3 files changed, 59 insertions(+)

diff --git a/gcc/config/nvptx/nvptx.md b/gcc/config/nvptx/nvptx.md
index 216e89f230ac..4989b5642e29 100644
--- a/gcc/config/nvptx/nvptx.md
+++ b/gcc/config/nvptx/nvptx.md
@@ -808,6 +808,22 @@
    ""
    "%.\\tshr.u%T0\\t%0, %1, %2;")

+(define_insn "rotlsi3"

+  [(set (match_operand:SI 0 "nvptx_register_operand" "=R")
+       (rotate:SI (match_operand:SI 1 "nvptx_register_operand" "R")
+                  (and:SI (match_operand:SI 2 "nvptx_nonmemory_operand" "Ri")
+                          (const_int 31))))]
+  "TARGET_SM35"
+  "%.\\tshf.l.wrap.b32\\t%0, %1, %1, %2;")
+
+(define_insn "rotrsi3"
+  [(set (match_operand:SI 0 "nvptx_register_operand" "=R")
+       (rotatert:SI (match_operand:SI 1 "nvptx_register_operand" "R")
+                    (and:SI (match_operand:SI 2 "nvptx_nonmemory_operand" "Ri")
+                            (const_int 31))))]
+  "TARGET_SM35"
+  "%.\\tshf.r.wrap.b32\\t%0, %1, %1, %2;")
+
  ;; Logical operations

(define_code_iterator any_logic [and ior xor])

diff --git a/gcc/testsuite/gcc.target/nvptx/rotate-run.c 
b/gcc/testsuite/gcc.target/nvptx/rotate-run.c
new file mode 100644
index 000000000000..14cb6f8b0b3f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/nvptx/rotate-run.c
@@ -0,0 +1,23 @@
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+#include "rotate.c"
+
+#define ASSERT(EXPR)                           \
+  do                                           \
+    {                                          \
+      if (!(EXPR))                             \
+       __builtin_abort ();                     \
+    } while (0)
+
+int
+main (void)
+{
+  ASSERT (rotl (0x12345678, 8) == 0x34567812);
+  ASSERT (rotl (0x12345678, 8 + 32) == 0x34567812);
+
+  ASSERT (rotr (0x12345678, 8) == 0x78123456);
+  ASSERT (rotr (0x12345678, 8 + 32) == 0x78123456);
+
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.target/nvptx/rotate.c 
b/gcc/testsuite/gcc.target/nvptx/rotate.c
new file mode 100644
index 000000000000..1c9b83b4809d
--- /dev/null
+++ b/gcc/testsuite/gcc.target/nvptx/rotate.c
@@ -0,0 +1,20 @@
+/* { dg-do assemble } */
+/* { dg-options "-O2 -save-temps" } */
+
+#define MASK 0x1f
+
+unsigned int
+rotl (unsigned int val, unsigned int cnt) {
+  cnt &= MASK;
+  return (val << cnt) | (val >> (-cnt & MASK));
+}
+
+unsigned int
+rotr (unsigned int val, unsigned int cnt) {
+  cnt &= MASK;
+  return (val >> cnt) | (val << (-cnt & MASK));
+}
+
+/* { dg-final { scan-assembler-times "shf.l.wrap.b32" 1 } } */
+/* { dg-final { scan-assembler-times "shf.r.wrap.b32" 1 } } */
+/* { dg-final { scan-assembler-not "and.b32" } } */