i386: Improve [QH]Imode rotates with masked shift count [PR99405]

The following testcase shows that while we nicely optimize away the
useless and? of shift count before rotation for [SD]Imode rotates,
we don't do that for [QH]Imode.

The following patch optimizes that by using the right iterator on those
4 patterns.

2021-04-27  Jakub Jelinek  <jakub@redhat.com>

	PR target/99405
	* config/i386/i386.md (*<insn><mode>3_mask, *<insn><mode>3_mask_1):
	For any_rotate define_insn_split and following splitters, use
	SWI iterator instead of SWI48.

	* gcc.target/i386/pr99405.c: New test.

diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index 27f100c9767212d76ca90d553b6efb6c451f5ab4..eff189f17b4d3e9c5e3960ca4f41a5f2835b7764 100644 (file)
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -11933,9 +11933,9 @@
 
 ;; Avoid useless masking of count operand.
 (define_insn_and_split "*<insn><mode>3_mask"
-  [(set (match_operand:SWI48 0 "nonimmediate_operand")
-       (any_rotate:SWI48
-         (match_operand:SWI48 1 "nonimmediate_operand")
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+       (any_rotate:SWI
+         (match_operand:SWI 1 "nonimmediate_operand")
          (subreg:QI
            (and:SI
              (match_operand:SI 2 "register_operand" "c")
@@ -11949,15 +11949,15 @@
   "&& 1"
   [(parallel
      [(set (match_dup 0)
-          (any_rotate:SWI48 (match_dup 1)
-                            (match_dup 2)))
+          (any_rotate:SWI (match_dup 1)
+                          (match_dup 2)))
       (clobber (reg:CC FLAGS_REG))])]
   "operands[2] = gen_lowpart (QImode, operands[2]);")
 
 (define_split
-  [(set (match_operand:SWI48 0 "register_operand")
-       (any_rotate:SWI48
-         (match_operand:SWI48 1 "const_int_operand")
+  [(set (match_operand:SWI 0 "register_operand")
+       (any_rotate:SWI
+         (match_operand:SWI 1 "const_int_operand")
          (subreg:QI
            (and:SI
              (match_operand:SI 2 "register_operand")
@@ -11966,14 +11966,14 @@
    == GET_MODE_BITSIZE (<MODE>mode) - 1"
  [(set (match_dup 4) (match_dup 1))
   (set (match_dup 0)
-       (any_rotate:SWI48 (match_dup 4)
-                        (subreg:QI (match_dup 2) 0)))]
+       (any_rotate:SWI (match_dup 4)
+                      (subreg:QI (match_dup 2) 0)))]
  "operands[4] = gen_reg_rtx (<MODE>mode);")
 
 (define_insn_and_split "*<insn><mode>3_mask_1"
-  [(set (match_operand:SWI48 0 "nonimmediate_operand")
-       (any_rotate:SWI48
-         (match_operand:SWI48 1 "nonimmediate_operand")
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+       (any_rotate:SWI
+         (match_operand:SWI 1 "nonimmediate_operand")
          (and:QI
            (match_operand:QI 2 "register_operand" "c")
            (match_operand:QI 3 "const_int_operand"))))
@@ -11986,14 +11986,14 @@
   "&& 1"
   [(parallel
      [(set (match_dup 0)
-          (any_rotate:SWI48 (match_dup 1)
-                            (match_dup 2)))
+          (any_rotate:SWI (match_dup 1)
+                          (match_dup 2)))
       (clobber (reg:CC FLAGS_REG))])])
 
 (define_split
-  [(set (match_operand:SWI48 0 "register_operand")
-       (any_rotate:SWI48
-         (match_operand:SWI48 1 "const_int_operand")
+  [(set (match_operand:SWI 0 "register_operand")
+       (any_rotate:SWI
+         (match_operand:SWI 1 "const_int_operand")
          (and:QI
            (match_operand:QI 2 "register_operand")
            (match_operand:QI 3 "const_int_operand"))))]
@@ -12001,7 +12001,7 @@
   == GET_MODE_BITSIZE (<MODE>mode) - 1"
  [(set (match_dup 4) (match_dup 1))
   (set (match_dup 0)
-       (any_rotate:SWI48 (match_dup 4) (match_dup 2)))]
+       (any_rotate:SWI (match_dup 4) (match_dup 2)))]
  "operands[4] = gen_reg_rtx (<MODE>mode);")
 
 ;; Implement rotation using two double-precision

diff --git a/gcc/testsuite/gcc.target/i386/pr99405.c b/gcc/testsuite/gcc.target/i386/pr99405.c
new file mode 100644 (file)
index 0000000..f3f49e3
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr99405.c
@@ -0,0 +1,23 @@
+/* PR target/99405 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -mtune=generic -fomit-frame-pointer" } */
+/* { dg-final { scan-assembler-not "\tand\[bl]\t\\\$" } } */
+
+unsigned char f1 (unsigned char x, unsigned y) { return (x << (y & 7)) | (x >> (-y & 7)); }
+unsigned short f2 (unsigned short x, unsigned y) { return (x << (y & 15)) | (x >> (-y & 15)); }
+unsigned int f3 (unsigned int x, unsigned y) { return (x << (y & 31)) | (x >> (-y & 31)); }
+unsigned char f4 (unsigned char x, unsigned y) { return (x >> (y & 7)) | (x << (-y & 7)); }
+unsigned short f5 (unsigned short x, unsigned y) { return (x >> (y & 15)) | (x << (-y & 15)); }
+unsigned int f6 (unsigned int x, unsigned y) { return (x >> (y & 31)) | (x << (-y & 31)); }
+unsigned char f7 (unsigned char x, unsigned char y) { unsigned char v = y & 7; unsigned char w = -y & 7; return (x << v) | (x >> w); }
+unsigned short f8 (unsigned short x, unsigned char y) { unsigned char v = y & 15; unsigned char w = -y & 15; return (x << v) | (x >> w); }
+unsigned int f9 (unsigned int x, unsigned char y) { unsigned char v = y & 31; unsigned char w = -y & 31; return (x << v) | (x >> w); }
+unsigned char f10 (unsigned char x, unsigned char y) { unsigned char v = y & 7; unsigned char w = -y & 7; return (x >> v) | (x << w); }
+unsigned short f11 (unsigned short x, unsigned char y) { unsigned char v = y & 15; unsigned char w = -y & 15; return (x >> v) | (x << w); }
+unsigned int f12 (unsigned int x, unsigned char y) { unsigned char v = y & 31; unsigned char w = -y & 31; return (x >> v) | (x << w); }
+#ifdef __x86_64__
+unsigned long long f13 (unsigned long long x, unsigned y) { return (x << (y & 63)) | (x >> (-y & 63)); }
+unsigned long long f14 (unsigned long long x, unsigned y) { return (x >> (y & 63)) | (x << (-y & 63)); }
+unsigned long long f15 (unsigned long long x, unsigned char y) { unsigned char v = y & 63; unsigned char w = -y & 63; return (x << v) | (x >> w); }
+unsigned long long f16 (unsigned long long x, unsigned char y) { unsigned char v = y & 63; unsigned char w = -y & 63; return (x >> v) | (x << w); }
+#endif