MATCH: (convert)(zero_one !=/== 0/1) for outer type and zero_one type are the same

When I moved two_value to match.pd, I removed the check for the {0,+-1}
as I had placed it after the {0,+-1} case for cond in match.pd.
In the case of {0,+-1} and non boolean, before we would optmize those
case to just `(convert)a` but after we would get `(convert)(a != 0)`
which was not handled anyways to just `(convert)a`.
So this adds a pattern to match `(convert)(zeroone != 0)` and simplify
to `(convert)zeroone`.

Also this optimizes (convert)(zeroone == 0) into (zeroone^1) if the
type match. Removing the opposite transformation from fold.
The opposite transformation was added with
https://gcc.gnu.org/pipermail/gcc-patches/2006-February/190514.html
It is no longer considered the canonicalization either, even VRP will
transform it back into `(~a) & 1` so removing it is a good idea.

Note the testcase pr69270.c needed a slight update due to not matching
exactly a scan pattern, this update makes it more robust and will match
before and afterwards and if there are other changes in this area too.

Note the testcase gcc.target/i386/pr110790-2.c needs a slight update
for better code generation in LP64 bit mode.

Bootstrapped and tested on x86_64-linux-gnu with no regressions.

gcc/ChangeLog:

	PR tree-optimization/111972
	PR tree-optimization/110637
	* match.pd (`(convert)(zeroone !=/== CST)`): Match
	and simplify to ((convert)zeroone){,^1}.
	* fold-const.cc (fold_binary_loc): Remove
	transformation of `(~a) & 1` and `(a ^ 1) & 1`
	into `(convert)(a == 0)`.

gcc/testsuite/ChangeLog:

	* gcc.dg/tree-ssa/pr110637-1.c: New test.
	* gcc.dg/tree-ssa/pr110637-2.c: New test.
	* gcc.dg/tree-ssa/pr110637-3.c: New test.
	* gcc.dg/tree-ssa/pr111972-1.c: New test.
	* gcc.dg/tree-ssa/pr69270.c: Update testcase.
	* gcc.target/i386/pr110790-2.c: Update testcase.
	* gcc.dg/fold-even-1.c: Removed.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>

diff --git a/gcc/fold-const.cc b/gcc/fold-const.cc
index 2692b98ceac2cf9f216a596a8ff876a4db4c8a59..f5d68ac323a1f287e69a47d27e5d759ed7d39c26 100644 (file)
--- a/gcc/fold-const.cc
+++ b/gcc/fold-const.cc
@@ -12077,33 +12077,6 @@ fold_binary_loc (location_t loc, enum tree_code code, tree type,
       goto bit_rotate;
 
     case BIT_AND_EXPR:
-      /* Fold (X ^ 1) & 1 as (X & 1) == 0.  */
-      if (TREE_CODE (arg0) == BIT_XOR_EXPR
-         && INTEGRAL_TYPE_P (type)
-         && integer_onep (TREE_OPERAND (arg0, 1))
-         && integer_onep (arg1))
-       {
-         tree tem2;
-         tem = TREE_OPERAND (arg0, 0);
-         tem2 = fold_convert_loc (loc, TREE_TYPE (tem), arg1);
-         tem2 = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem),
-                                 tem, tem2);
-         return fold_build2_loc (loc, EQ_EXPR, type, tem2,
-                                 build_zero_cst (TREE_TYPE (tem)));
-       }
-      /* Fold ~X & 1 as (X & 1) == 0.  */
-      if (TREE_CODE (arg0) == BIT_NOT_EXPR
-         && INTEGRAL_TYPE_P (type)
-         && integer_onep (arg1))
-       {
-         tree tem2;
-         tem = TREE_OPERAND (arg0, 0);
-         tem2 = fold_convert_loc (loc, TREE_TYPE (tem), arg1);
-         tem2 = fold_build2_loc (loc, BIT_AND_EXPR, TREE_TYPE (tem),
-                                 tem, tem2);
-         return fold_build2_loc (loc, EQ_EXPR, type, tem2,
-                                 build_zero_cst (TREE_TYPE (tem)));
-       }
       /* Fold !X & 1 as X == 0.  */
       if (TREE_CODE (arg0) == TRUTH_NOT_EXPR
          && integer_onep (arg1))

diff --git a/gcc/match.pd b/gcc/match.pd
index 5deddd57d21ef94d45575f5e2c9d069a6467c03b..15bca217aafba4873cbcb4daa81eb1c80a7a7cf3 100644 (file)
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -3332,6 +3332,22 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
   (if (INTEGRAL_TYPE_P (TREE_TYPE (@0)) || POINTER_TYPE_P (TREE_TYPE (@0)))
     (rcmp @0 @1))))
 
+/* (type)([0,1]@a != 0) -> (type)a
+   (type)([0,1]@a == 1) -> (type)a
+   (type)([0,1]@a == 0) -> a ^ 1
+   (type)([0,1]@a != 1) -> a ^ 1.  */
+(for eqne (eq ne)
+ (simplify
+  (convert (eqne zero_one_valued_p@0 INTEGER_CST@1))
+  (if ((integer_zerop (@1) || integer_onep (@1)))
+   (if ((eqne == EQ_EXPR) ^ integer_zerop (@1))
+    (convert @0)
+    /* Only do this if the types match as (type)(a == 0) is
+       canonical form normally, while `a ^ 1` is canonical when
+       there is no type change. */
+    (if (types_match (type, TREE_TYPE (@0)))
+     (bit_xor @0 { build_one_cst (type); } ))))))
+
 /* We can't reassociate at all for saturating types.  */
 (if (!TYPE_SATURATING (type))
 

diff --git a/gcc/testsuite/gcc.dg/fold-even-1.c b/gcc/testsuite/gcc.dg/fold-even-1.c
deleted file mode 100644 (file)
index 94711ab..0000000
--- a/gcc/testsuite/gcc.dg/fold-even-1.c
+++ /dev/null
@@ -1,32 +0,0 @@
-/* { dg-do compile } */
-/* { dg-options "-O2 -fdump-tree-original" } */
-int test1(int a)
-{
-  return !(a & 1);
-}
-
-int test2(int b)
-{
-  return (b & 1) == 0;
-}
-
-int test3(int c)
-{
-  return (c & 1) ^ 1;
-}
-
-int test4(int d)
-{
-  return (d ^ 1) & 1;
-}
-
-int test5(int e)
-{
-  return ~e & 1;
-}
-
-/* { dg-final { scan-tree-dump-times "\\(a \& 1\\) == 0" 1 "original" } } */
-/* { dg-final { scan-tree-dump-times "\\(b \& 1\\) == 0" 1 "original" } } */
-/* { dg-final { scan-tree-dump-times "\\(c \& 1\\) == 0" 1 "original" } } */
-/* { dg-final { scan-tree-dump-times "\\(d \& 1\\) == 0" 1 "original" } } */
-/* { dg-final { scan-tree-dump-times "\\(e \& 1\\) == 0" 1 "original" } } */

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr110637-1.c b/gcc/testsuite/gcc.dg/tree-ssa/pr110637-1.c
new file mode 100644 (file)
index 0000000..3d03b09
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr110637-1.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+int f(int a)
+{
+        int b = (a & 1)!=0;
+        return b;
+}
+
+/* This should be optimized to just return (a & 1); */
+/* { dg-final { scan-tree-dump-not " == " "optimized"} } */

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr110637-2.c b/gcc/testsuite/gcc.dg/tree-ssa/pr110637-2.c
new file mode 100644 (file)
index 0000000..f1c5b90
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr110637-2.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+int f(int a)
+{
+        int b = a & 1;
+        int c = b == 0;
+        return c;
+}
+
+/* This should be optimized to just return `(a&1) ^ 1` or `(~a) & 1`. */
+/* { dg-final { scan-tree-dump-not " == " "optimized"} } */
+/* { dg-final { scan-tree-dump-times "~a" 1 "optimized"} } */
+/* { dg-final { scan-tree-dump-times " & 1" 1 "optimized"} } */

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr110637-3.c b/gcc/testsuite/gcc.dg/tree-ssa/pr110637-3.c
new file mode 100644 (file)
index 0000000..ce80146
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr110637-3.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+int f(int a)
+{
+        int b = a & 1;
+        int c = b == 0;
+        int d = ~a;
+        int e = d & 1;
+        return c == e;
+}
+
+/* This should be optimized to just `return 1` */
+/* { dg-final { scan-tree-dump-not " == " "optimized"} } */
+/* { dg-final { scan-tree-dump-times "return 1" 1 "optimized"} } */

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr111972-1.c b/gcc/testsuite/gcc.dg/tree-ssa/pr111972-1.c
new file mode 100644 (file)
index 0000000..0611808
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr111972-1.c
@@ -0,0 +1,34 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-phiopt" } */
+double
+foo() {
+  long n3 = 3450000, xtra = 7270;
+  long i,ix;
+  long j;
+  double Check;
+
+  /* Section 3, Conditional jumps */
+  j = 0;
+  {
+    for (ix=0; ix<xtra; ix++)
+      {
+        for(i=0; i<n3; i++)
+          {
+            if(j==1)       j = 2;
+            else           j = 3;
+            if(j>2)        j = 0;
+            else           j = 1;
+            if(j<1)        j = 1;
+            else           j = 0;
+          }
+      }
+  }
+  Check = Check + (double)j;
+  return Check;
+}
+
+/* the above if statements in loop should be optimized to just `j ^ 1`
+   and should not be (type)(j != 1).  */
+/* { dg-final { scan-tree-dump-not " != 1" "phiopt2"} } */
+/* { dg-final { scan-tree-dump-times " \\^ 1" 1 "phiopt2"} } */
+

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr69270.c b/gcc/testsuite/gcc.dg/tree-ssa/pr69270.c
index 0d66cc4383f2d77ba9cf05ff52de8a1bea8d452a..b08ec9d6ddb445720930b54c60282951f4ed4159 100644 (file)
--- a/gcc/testsuite/gcc.dg/tree-ssa/pr69270.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr69270.c
@@ -7,8 +7,8 @@
 /* { dg-final { scan-tree-dump-times "Replaced .bufferstep_\[0-9\]+. with constant .1." 1 "dom3"} } */
 
 /* And some assignments ought to fold down to constants.  */
-/* { dg-final { scan-tree-dump-times "Folded to: _\[0-9\]+ = 1;" 1 "dom3"} } */
-/* { dg-final { scan-tree-dump-times "Folded to: _\[0-9\]+ = 0;" 1 "dom3"} } */
+/* { dg-final { scan-tree-dump-times "Folded to: (?:bufferstep)?_\[0-9\]+ = 1;" 1 "dom3"} } */
+/* { dg-final { scan-tree-dump-times "Folded to: (?:bufferstep)?_\[0-9\]+ = 0;" 1 "dom3"} } */
 
 /* The XOR operations should have been optimized to constants.  */
 /* { dg-final { scan-tree-dump-not "bit_xor" "dom3"} } */

diff --git a/gcc/testsuite/gcc.target/i386/pr110790-2.c b/gcc/testsuite/gcc.target/i386/pr110790-2.c
index 8b9d650c6e9b012cdebacbdc323c178d4f8b786b..16c73cb74659dcf653241d1c46ad8494d0350f68 100644 (file)
--- a/gcc/testsuite/gcc.target/i386/pr110790-2.c
+++ b/gcc/testsuite/gcc.target/i386/pr110790-2.c
@@ -9,5 +9,17 @@ refmpn_tstbit_bad (mp_srcptr ptr, unsigned long bit)
   return (((ptr)[(bit)/(32 - 0)] & (((mp_limb_t) 1L) << ((bit)%(32 - 0)))) != 0);
 }
 
-/* { dg-final { scan-assembler "bt\[ql\]" } } */
-/* { dg-final { scan-assembler "setc" } } */
+/* 32bit produces:
+        btl     %eax, %edx
+        setc    %al
+        movzbl  %al, %eax
+ */
+/* { dg-final { scan-assembler "bt\[ql\]" { target { ! lp64 } } } } */
+/* { dg-final { scan-assembler "setc" { target {  ! lp64 } } } } */
+
+/* 64bit produces:
+        shrq    %cl, %rax
+        andl   $1, %eax
+ */
+/* { dg-final { scan-assembler-times "shrq" 2 { target { lp64 } } } } */
+/* { dg-final { scan-assembler-times "andl" 2 { target { lp64 } } } } */