Fix the shift patterns, and add test
authorSegher Boessenkool <segher@kernel.crashing.org>
Thu, 3 Jul 2014 16:39:58 +0000 (18:39 +0200)
committerSegher Boessenkool <segher@gcc.gnu.org>
Thu, 3 Jul 2014 16:39:58 +0000 (18:39 +0200)
Firstly, it adds back the split conditions that I accidentally removed.
Without it the dot insns are never generated, or rather, always split
back to a separate compare instruction.

Secondly, the shift amount should be SI always, not GPR, or GCC will
insert a zero-extend at expand time that it cannot get rid of later.

The test tests whether dot-form instructions are generated for both
"dot" and "dot2" cases, that is, with just a CC output or also a GPR
output; for all four basic shifts, with a register amount or an
immediate amount.  It also tests for superfluous zero-extends.  This
also tests if combine "simplifies" the rotates to right-rotates, which
it shouldn't do anymore.

From-SVN: r212267

gcc/ChangeLog
gcc/config/rs6000/rs6000.md
gcc/testsuite/ChangeLog
gcc/testsuite/gcc.target/powerpc/shift-dot.c [new file with mode: 0644]

index 6f83e8c..de5484e 100644 (file)
@@ -1,3 +1,11 @@
+2014-07-03  Segher Boessenkool  <segher@kernel.crashing.org>
+
+       * config/rs6000/rs6000.md (rotl<mode>3, ashl<mode>3, lshr<mode>3,
+       ashr<mode>3): Correct mode of operands[2].
+       (rotl<mode>3_dot, rotl<mode>3_dot2, ashl<mode>3_dot, ashl<mode>3_dot2,
+       lshr<mode>3_dot, lshr<mode>3_dot2, ashr<mode>3_dot, ashr<mode>3_dot2):
+       Correct mode of operands[2].  Fix split condition.
+
 2014-07-03  Richard Earnshaw  <rearnsha@arm.com>
 
        * arm.md (arch): Add armv6_or_vfpv3.
index 8e9039e..83aaa58 100644 (file)
 (define_insn "rotl<mode>3"
   [(set (match_operand:GPR 0 "gpc_reg_operand" "=r")
        (rotate:GPR (match_operand:GPR 1 "gpc_reg_operand" "r")
-                   (match_operand:GPR 2 "reg_or_cint_operand" "rn")))]
+                   (match_operand:SI 2 "reg_or_cint_operand" "rn")))]
   ""
   "rotl<wd>%I2 %0,%1,%<hH>2"
   [(set_attr "type" "shift")
 (define_insn_and_split "*rotl<mode>3_dot"
   [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y")
        (compare:CC (rotate:GPR (match_operand:GPR 1 "gpc_reg_operand" "r,r")
-                               (match_operand:GPR 2 "reg_or_cint_operand" "rn,rn"))
+                               (match_operand:SI 2 "reg_or_cint_operand" "rn,rn"))
                    (const_int 0)))
    (clobber (match_scratch:GPR 0 "=r,r"))]
   "<MODE>mode == Pmode && rs6000_gen_cell_microcode"
   "@
    rotl<wd>%I2. %0,%1,%<hH>2
    #"
-  "&& reload_completed"
+  "&& reload_completed && cc_reg_not_cr0_operand (operands[3], CCmode)"
   [(set (match_dup 0)
        (rotate:GPR (match_dup 1)
                    (match_dup 2)))
 (define_insn_and_split "*rotl<mode>3_dot2"
   [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y")
        (compare:CC (rotate:GPR (match_operand:GPR 1 "gpc_reg_operand" "r,r")
-                               (match_operand:GPR 2 "reg_or_cint_operand" "rn,rn"))
+                               (match_operand:SI 2 "reg_or_cint_operand" "rn,rn"))
                    (const_int 0)))
    (set (match_operand:GPR 0 "gpc_reg_operand" "=r,r")
        (rotate:GPR (match_dup 1)
   "@
    rotl<wd>%I2. %0,%1,%<hH>2
    #"
-  "&& reload_completed"
+  "&& reload_completed && cc_reg_not_cr0_operand (operands[3], CCmode)"
   [(set (match_dup 0)
        (rotate:GPR (match_dup 1)
                    (match_dup 2)))
 (define_insn "ashl<mode>3"
   [(set (match_operand:GPR 0 "gpc_reg_operand" "=r")
        (ashift:GPR (match_operand:GPR 1 "gpc_reg_operand" "r")
-                   (match_operand:GPR 2 "reg_or_cint_operand" "rn")))]
+                   (match_operand:SI 2 "reg_or_cint_operand" "rn")))]
   ""
   "sl<wd>%I2 %0,%1,%<hH>2"
   [(set_attr "type" "shift")
 (define_insn_and_split "*ashl<mode>3_dot"
   [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y")
        (compare:CC (ashift:GPR (match_operand:GPR 1 "gpc_reg_operand" "r,r")
-                               (match_operand:GPR 2 "reg_or_cint_operand" "rn,rn"))
+                               (match_operand:SI 2 "reg_or_cint_operand" "rn,rn"))
                    (const_int 0)))
    (clobber (match_scratch:GPR 0 "=r,r"))]
   "<MODE>mode == Pmode && rs6000_gen_cell_microcode"
   "@
    sl<wd>%I2. %0,%1,%<hH>2
    #"
-  "&& reload_completed"
+  "&& reload_completed && cc_reg_not_cr0_operand (operands[3], CCmode)"
   [(set (match_dup 0)
        (ashift:GPR (match_dup 1)
                    (match_dup 2)))
 (define_insn_and_split "*ashl<mode>3_dot2"
   [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y")
        (compare:CC (ashift:GPR (match_operand:GPR 1 "gpc_reg_operand" "r,r")
-                               (match_operand:GPR 2 "reg_or_cint_operand" "rn,rn"))
+                               (match_operand:SI 2 "reg_or_cint_operand" "rn,rn"))
                    (const_int 0)))
    (set (match_operand:GPR 0 "gpc_reg_operand" "=r,r")
        (ashift:GPR (match_dup 1)
   "@
    sl<wd>%I2. %0,%1,%<hH>2
    #"
-  "&& reload_completed"
+  "&& reload_completed && cc_reg_not_cr0_operand (operands[3], CCmode)"
   [(set (match_dup 0)
        (ashift:GPR (match_dup 1)
                    (match_dup 2)))
 (define_insn "lshr<mode>3"
   [(set (match_operand:GPR 0 "gpc_reg_operand" "=r")
        (lshiftrt:GPR (match_operand:GPR 1 "gpc_reg_operand" "r")
-                     (match_operand:GPR 2 "reg_or_cint_operand" "rn")))]
+                     (match_operand:SI 2 "reg_or_cint_operand" "rn")))]
   ""
   "sr<wd>%I2 %0,%1,%<hH>2"
   [(set_attr "type" "shift")
 (define_insn_and_split "*lshr<mode>3_dot"
   [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y")
        (compare:CC (lshiftrt:GPR (match_operand:GPR 1 "gpc_reg_operand" "r,r")
-                                 (match_operand:GPR 2 "reg_or_cint_operand" "rn,rn"))
+                                 (match_operand:SI 2 "reg_or_cint_operand" "rn,rn"))
                    (const_int 0)))
    (clobber (match_scratch:GPR 0 "=r,r"))]
   "<MODE>mode == Pmode && rs6000_gen_cell_microcode"
   "@
    sr<wd>%I2. %0,%1,%<hH>2
    #"
-  "&& reload_completed"
+  "&& reload_completed && cc_reg_not_cr0_operand (operands[3], CCmode)"
   [(set (match_dup 0)
        (lshiftrt:GPR (match_dup 1)
                      (match_dup 2)))
 (define_insn_and_split "*lshr<mode>3_dot2"
   [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y")
        (compare:CC (lshiftrt:GPR (match_operand:GPR 1 "gpc_reg_operand" "r,r")
-                                 (match_operand:GPR 2 "reg_or_cint_operand" "rn,rn"))
+                                 (match_operand:SI 2 "reg_or_cint_operand" "rn,rn"))
                    (const_int 0)))
    (set (match_operand:GPR 0 "gpc_reg_operand" "=r,r")
        (lshiftrt:GPR (match_dup 1)
   "@
    sr<wd>%I2. %0,%1,%<hH>2
    #"
-  "&& reload_completed"
+  "&& reload_completed && cc_reg_not_cr0_operand (operands[3], CCmode)"
   [(set (match_dup 0)
        (lshiftrt:GPR (match_dup 1)
                      (match_dup 2)))
 (define_expand "ashr<mode>3"
   [(set (match_operand:GPR 0 "gpc_reg_operand" "")
        (ashiftrt:GPR (match_operand:GPR 1 "gpc_reg_operand" "")
-                     (match_operand:GPR 2 "reg_or_cint_operand" "")))]
+                     (match_operand:SI 2 "reg_or_cint_operand" "")))]
   ""
 {
   /* The generic code does not generate optimal code for the low word
 (define_insn "*ashr<mode>3"
   [(set (match_operand:GPR 0 "gpc_reg_operand" "=r")
        (ashiftrt:GPR (match_operand:GPR 1 "gpc_reg_operand" "r")
-                     (match_operand:GPR 2 "reg_or_cint_operand" "rn")))]
+                     (match_operand:SI 2 "reg_or_cint_operand" "rn")))]
   ""
   "sra<wd>%I2 %0,%1,%<hH>2"
   [(set_attr "type" "shift")
 (define_insn_and_split "*ashr<mode>3_dot"
   [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y")
        (compare:CC (ashiftrt:GPR (match_operand:GPR 1 "gpc_reg_operand" "r,r")
-                                 (match_operand:GPR 2 "reg_or_cint_operand" "rn,rn"))
+                                 (match_operand:SI 2 "reg_or_cint_operand" "rn,rn"))
                    (const_int 0)))
    (clobber (match_scratch:GPR 0 "=r,r"))]
   "<MODE>mode == Pmode && rs6000_gen_cell_microcode"
   "@
    sra<wd>%I2. %0,%1,%<hH>2
    #"
-  "&& reload_completed"
+  "&& reload_completed && cc_reg_not_cr0_operand (operands[3], CCmode)"
   [(set (match_dup 0)
        (ashiftrt:GPR (match_dup 1)
                      (match_dup 2)))
 (define_insn_and_split "*ashr<mode>3_dot2"
   [(set (match_operand:CC 3 "cc_reg_operand" "=x,?y")
        (compare:CC (ashiftrt:GPR (match_operand:GPR 1 "gpc_reg_operand" "r,r")
-                                 (match_operand:GPR 2 "reg_or_cint_operand" "rn,rn"))
+                                 (match_operand:SI 2 "reg_or_cint_operand" "rn,rn"))
                    (const_int 0)))
    (set (match_operand:GPR 0 "gpc_reg_operand" "=r,r")
        (ashiftrt:GPR (match_dup 1)
   "@
    sra<wd>%I2. %0,%1,%<hH>2
    #"
-  "&& reload_completed"
+  "&& reload_completed && cc_reg_not_cr0_operand (operands[3], CCmode)"
   [(set (match_dup 0)
        (ashiftrt:GPR (match_dup 1)
                      (match_dup 2)))
index 886a964..50831eb 100644 (file)
@@ -1,3 +1,7 @@
+2014-07-03  Segher Boessenkool  <segher@kernel.crashing.org>
+
+       * gcc.target/powerpc/shift-dot.c: New test.
+
 2014-07-03  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>
 
        * gfortran.dg/ieee/ieee_1.F90: Mark variables as volatile to
diff --git a/gcc/testsuite/gcc.target/powerpc/shift-dot.c b/gcc/testsuite/gcc.target/powerpc/shift-dot.c
new file mode 100644 (file)
index 0000000..002948c
--- /dev/null
@@ -0,0 +1,49 @@
+/* Check that record-form instructions are used.  */
+
+/* { dg-do compile } */
+/* { dg-options "-O2 -mgen-cell-microcode" } */
+
+/* { dg-final { scan-assembler-times {\mrotl[wd]\.} 2 } } */
+/* { dg-final { scan-assembler-times {\msl[wd]\.} 2 } } */
+/* { dg-final { scan-assembler-times {\msr[wd]\.} 2 } } */
+/* { dg-final { scan-assembler-times {\msra[wd]\.} 2 } } */
+
+/* { dg-final { scan-assembler-times {\mrotl[wd]i\.} 2 } } */
+/* { dg-final { scan-assembler-times {\msl[wd]i\.} 2 } } */
+/* { dg-final { scan-assembler-times {\msr[wd]i\.} 2 } } */
+/* Combine converts the arith shift right compares to a (more expensive)
+   direct compare.  Luckily not the other shifts.  XFAIL for now.  */
+/* { dg-final { scan-assembler-times {\msra[wd]i\.} 2 { xfail *-*-* } } } */
+
+/* There should not be any extends of the shift amount (or anything else).  */
+/* { dg-final { scan-assembler-not {\mextsw\M} } } */
+/* { dg-final { scan-assembler-not {\mrldicl\M} } } */
+/* { dg-final { scan-assembler-not {\mclrldi\M} } } */
+/* { dg-final { scan-assembler-not {\mrlwinm\M} } } */
+
+
+typedef unsigned long u;
+typedef long s;
+#define M(n) (8 * sizeof(long) - (n))
+#define T1 if ((s)x > 0) g();
+#define T2 if ((s)x > 0) g(); return x;
+
+void g(void);
+
+void rot1(u x, u n) { x = (x << M(n)) | (x >> n); T1 }
+   u rot2(u x, u n) { x = (x << M(n)) | (x >> n); T2 }
+void shl1(u x, u n) { x <<= n; T1 }
+   u shl2(u x, u n) { x <<= n; T2 }
+void shr1(u x, u n) { x >>= n; T1 }
+   u shr2(u x, u n) { x >>= n; T2 }
+void asr1(s x, u n) { x >>= n; T1 }
+   s asr2(s x, u n) { x >>= n; T2 }
+
+void rot1i(u x) { x = (x << M(23)) | (x >> 23); T1 }
+   u rot2i(u x) { x = (x << M(23)) | (x >> 23); T2 }
+void shl1i(u x) { x <<= 23; T1 }
+   u shl2i(u x) { x <<= 23; T2 }
+void shr1i(u x) { x >>= 23; T1 }
+   u shr2i(u x) { x >>= 23; T2 }
+void asr1i(s x) { x >>= 23; T1 }
+   s asr2i(s x) { x >>= 23; T2 }