bpf: add define_insn for bswap

Message ID 20221208183540.8667-1-david.faust@oracle.com
State Committed
Commit 5ddfe794405a514824382e96b1047d3195af23cc
Headers
Series bpf: add define_insn for bswap |

Commit Message

David Faust Dec. 8, 2022, 6:35 p.m. UTC
  The eBPF architecture provides 'end[be,le]' instructions for endianness
swapping. Add a define_insn for bswap<mode>2 to use them instaed of
falling back on a libcall.

Tested on bpf-unknown-none, no known regressions.

OK to commit?
Thanks

gcc/

	* config/bpf/bpf.md (bswap<mode>2): New define_insn.

gcc/testsuite/

	* gcc.target/bpf/bswap-1.c: New test.
---
 gcc/config/bpf/bpf.md                  | 17 +++++++++++++++++
 gcc/testsuite/gcc.target/bpf/bswap-1.c | 23 +++++++++++++++++++++++
 2 files changed, 40 insertions(+)
 create mode 100644 gcc/testsuite/gcc.target/bpf/bswap-1.c
  

Comments

Jose E. Marchesi Dec. 8, 2022, 6:50 p.m. UTC | #1
Hi David.

> The eBPF architecture provides 'end[be,le]' instructions for endianness
> swapping. Add a define_insn for bswap<mode>2 to use them instaed of
> falling back on a libcall.
>
> Tested on bpf-unknown-none, no known regressions.
>
> OK to commit?
> Thanks

OK for master.
Thanks!

> gcc/
>
> 	* config/bpf/bpf.md (bswap<mode>2): New define_insn.
>
> gcc/testsuite/
>
> 	* gcc.target/bpf/bswap-1.c: New test.
> ---
>  gcc/config/bpf/bpf.md                  | 17 +++++++++++++++++
>  gcc/testsuite/gcc.target/bpf/bswap-1.c | 23 +++++++++++++++++++++++
>  2 files changed, 40 insertions(+)
>  create mode 100644 gcc/testsuite/gcc.target/bpf/bswap-1.c
>
> diff --git a/gcc/config/bpf/bpf.md b/gcc/config/bpf/bpf.md
> index a28021aef26..22a133f1c79 100644
> --- a/gcc/config/bpf/bpf.md
> +++ b/gcc/config/bpf/bpf.md
> @@ -341,6 +341,23 @@ (define_insn "lshr<SIM:mode>3"
>    "rsh<msuffix>\t%0,%2"
>    [(set_attr "type" "<mtype>")])
>  
> +;;;; Endianness conversion
> +
> +(define_mode_iterator BSM [HI SI DI])
> +(define_mode_attr endmode [(HI "16") (SI "32") (DI "64")])
> +
> +(define_insn "bswap<BSM:mode>2"
> +  [(set (match_operand:BSM 0 "register_operand"            "=r")
> +        (bswap:BSM (match_operand:BSM 1 "register_operand" " r")))]
> +  ""
> +{
> +  if (TARGET_BIG_ENDIAN)
> +    return "endle\t%0, <endmode>";
> +  else
> +    return "endbe\t%0, <endmode>";
> +}
> +  [(set_attr "type" "end")])
> +
>  ;;;; Conditional branches
>  
>  ;; The eBPF jump instructions use 64-bit arithmetic when evaluating
> diff --git a/gcc/testsuite/gcc.target/bpf/bswap-1.c b/gcc/testsuite/gcc.target/bpf/bswap-1.c
> new file mode 100644
> index 00000000000..4748143ada5
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/bpf/bswap-1.c
> @@ -0,0 +1,23 @@
> +/* { dg-do compile } */
> +/* { dg-options "-mlittle-endian" } */
> +
> +unsigned short in16 = 0x1234U;
> +unsigned int   in32 = 0x12345678U;
> +unsigned long  in64 = 0x123456789abcdef0ULL;
> +
> +unsigned short out16 = 0;
> +unsigned int   out32 = 0;
> +unsigned long  out64 = 0;
> +
> +int foo (void)
> +{
> +  out16 = __builtin_bswap16 (in16);
> +  out32 = __builtin_bswap32 (in32);
> +  out64 = __builtin_bswap64 (in64);
> +
> +  return 0;
> +}
> +
> +/* { dg-final { scan-assembler "endbe\t%r., 16" } } */
> +/* { dg-final { scan-assembler "endbe\t%r., 32" } } */
> +/* { dg-final { scan-assembler "endbe\t%r., 64" } } */
  

Patch

diff --git a/gcc/config/bpf/bpf.md b/gcc/config/bpf/bpf.md
index a28021aef26..22a133f1c79 100644
--- a/gcc/config/bpf/bpf.md
+++ b/gcc/config/bpf/bpf.md
@@ -341,6 +341,23 @@  (define_insn "lshr<SIM:mode>3"
   "rsh<msuffix>\t%0,%2"
   [(set_attr "type" "<mtype>")])
 
+;;;; Endianness conversion
+
+(define_mode_iterator BSM [HI SI DI])
+(define_mode_attr endmode [(HI "16") (SI "32") (DI "64")])
+
+(define_insn "bswap<BSM:mode>2"
+  [(set (match_operand:BSM 0 "register_operand"            "=r")
+        (bswap:BSM (match_operand:BSM 1 "register_operand" " r")))]
+  ""
+{
+  if (TARGET_BIG_ENDIAN)
+    return "endle\t%0, <endmode>";
+  else
+    return "endbe\t%0, <endmode>";
+}
+  [(set_attr "type" "end")])
+
 ;;;; Conditional branches
 
 ;; The eBPF jump instructions use 64-bit arithmetic when evaluating
diff --git a/gcc/testsuite/gcc.target/bpf/bswap-1.c b/gcc/testsuite/gcc.target/bpf/bswap-1.c
new file mode 100644
index 00000000000..4748143ada5
--- /dev/null
+++ b/gcc/testsuite/gcc.target/bpf/bswap-1.c
@@ -0,0 +1,23 @@ 
+/* { dg-do compile } */
+/* { dg-options "-mlittle-endian" } */
+
+unsigned short in16 = 0x1234U;
+unsigned int   in32 = 0x12345678U;
+unsigned long  in64 = 0x123456789abcdef0ULL;
+
+unsigned short out16 = 0;
+unsigned int   out32 = 0;
+unsigned long  out64 = 0;
+
+int foo (void)
+{
+  out16 = __builtin_bswap16 (in16);
+  out32 = __builtin_bswap32 (in32);
+  out64 = __builtin_bswap64 (in64);
+
+  return 0;
+}
+
+/* { dg-final { scan-assembler "endbe\t%r., 16" } } */
+/* { dg-final { scan-assembler "endbe\t%r., 32" } } */
+/* { dg-final { scan-assembler "endbe\t%r., 64" } } */