re PR target/92140 (clang vs gcc optimizing with adc/sbb)

	PR target/92140
	* config/i386/predicates.md (int_nonimmediate_operand): New special
	predicate.
	* config/i386/i386.md (*add<mode>3_eq, *add<mode>3_ne,
	*add<mode>3_eq_0, *add<mode>3_ne_0, *sub<mode>3_eq, *sub<mode>3_ne,
	*sub<mode>3_eq_1, *sub<mode>3_eq_0, *sub<mode>3_ne_0): New
	define_insn_and_split patterns.

	* gcc.target/i386/pr92140.c: New test.
	* gcc.c-torture/execute/pr92140.c: New test.

Co-Authored-By: Uros Bizjak <ubizjak@gmail.com>

From-SVN: r277203

6 files changed, 369 insertions, 0 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 7f77088..4919539 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,14 @@
+2019-10-19  Jakub Jelinek  <jakub@redhat.com>
+	    Uroš Bizjak  <ubizjak@gmail.com>
+
+	PR target/92140
+	* config/i386/predicates.md (int_nonimmediate_operand): New special
+	predicate.
+	* config/i386/i386.md (*add<mode>3_eq, *add<mode>3_ne,
+	*add<mode>3_eq_0, *add<mode>3_ne_0, *sub<mode>3_eq, *sub<mode>3_ne,
+	*sub<mode>3_eq_1, *sub<mode>3_eq_0, *sub<mode>3_ne_0): New
+	define_insn_and_split patterns.
+
 2019-10-19  Iain Sandoe  <iain@sandoe.co.uk>
 
 	* config/rs6000/rs6000.md: Delete out--of-date comment about
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index b7e7d12..a1b849e 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -6843,6 +6843,228 @@
   [(set_attr "type" "alu")
    (set_attr "mode" "SI")])
 
+;; x == 0 with zero flag test can be done also as x < 1U with carry flag
+;; test, where the latter is preferrable if we have some carry consuming
+;; instruction.
+;; For x != 0, we need to use x < 1U with negation of carry, i.e.
+;; + (1 - CF).
+(define_insn_and_split "*add<mode>3_eq"
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+	(plus:SWI
+	  (plus:SWI
+	    (eq:SWI (match_operand 3 "int_nonimmediate_operand") (const_int 0))
+	    (match_operand:SWI 1 "nonimmediate_operand"))
+	  (match_operand:SWI 2 "<general_operand>")))
+   (clobber (reg:CC FLAGS_REG))]
+  "ix86_binary_operator_ok (PLUS, <MODE>mode, operands)
+   && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (reg:CC FLAGS_REG)
+	(compare:CC (match_dup 3) (const_int 1)))
+   (parallel [(set (match_dup 0)
+		   (plus:SWI
+		     (plus:SWI (ltu:SWI (reg:CC FLAGS_REG) (const_int 0))
+			       (match_dup 1))
+		     (match_dup 2)))
+	      (clobber (reg:CC FLAGS_REG))])])
+
+(define_insn_and_split "*add<mode>3_ne"
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+	(plus:SWI
+	  (plus:SWI
+	    (ne:SWI (match_operand 3 "int_nonimmediate_operand") (const_int 0))
+	    (match_operand:SWI 1 "nonimmediate_operand"))
+	  (match_operand:SWI 2 "<immediate_operand>")))
+   (clobber (reg:CC FLAGS_REG))]
+  "CONST_INT_P (operands[2])
+   && (<MODE>mode != DImode
+       || INTVAL (operands[2]) != HOST_WIDE_INT_C (-0x80000000))
+   && ix86_binary_operator_ok (PLUS, <MODE>mode, operands)
+   && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (reg:CC FLAGS_REG)
+	(compare:CC (match_dup 3) (const_int 1)))
+   (parallel [(set (match_dup 0)
+		   (minus:SWI
+		     (minus:SWI (match_dup 1)
+				(ltu:SWI (reg:CC FLAGS_REG) (const_int 0)))
+		     (match_dup 2)))
+	      (clobber (reg:CC FLAGS_REG))])]
+{
+  operands[2] = gen_int_mode (~INTVAL (operands[2]),
+			      <MODE>mode == DImode ? SImode : <MODE>mode);
+})
+
+(define_insn_and_split "*add<mode>3_eq_0"
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+	(plus:SWI
+	  (eq:SWI (match_operand 2 "int_nonimmediate_operand") (const_int 0))
+	  (match_operand:SWI 1 "<general_operand>")))
+   (clobber (reg:CC FLAGS_REG))]
+  "ix86_unary_operator_ok (PLUS, <MODE>mode, operands)
+   && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (reg:CC FLAGS_REG)
+	(compare:CC (match_dup 2) (const_int 1)))
+   (parallel [(set (match_dup 0)
+		   (plus:SWI (ltu:SWI (reg:CC FLAGS_REG) (const_int 0))
+			     (match_dup 1)))
+	      (clobber (reg:CC FLAGS_REG))])]
+{
+  if (!nonimmediate_operand (operands[1], <MODE>mode))
+    operands[1] = force_reg (<MODE>mode, operands[1]);
+})
+
+(define_insn_and_split "*add<mode>3_ne_0"
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+	(plus:SWI
+	  (ne:SWI (match_operand 2 "int_nonimmediate_operand") (const_int 0))
+	  (match_operand:SWI 1 "<general_operand>")))
+   (clobber (reg:CC FLAGS_REG))]
+  "ix86_unary_operator_ok (PLUS, <MODE>mode, operands)
+   && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (reg:CC FLAGS_REG)
+	(compare:CC (match_dup 2) (const_int 1)))
+   (parallel [(set (match_dup 0)
+		   (minus:SWI (minus:SWI
+				(match_dup 1)
+				(ltu:SWI (reg:CC FLAGS_REG) (const_int 0)))
+			      (const_int -1)))
+	      (clobber (reg:CC FLAGS_REG))])]
+{
+  if (!nonimmediate_operand (operands[1], <MODE>mode))
+    operands[1] = force_reg (<MODE>mode, operands[1]);
+})
+
+(define_insn_and_split "*sub<mode>3_eq"
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+	(minus:SWI
+	  (minus:SWI
+	    (match_operand:SWI 1 "nonimmediate_operand")
+	    (eq:SWI (match_operand 3 "int_nonimmediate_operand")
+		    (const_int 0)))
+	  (match_operand:SWI 2 "<general_operand>")))
+   (clobber (reg:CC FLAGS_REG))]
+  "ix86_binary_operator_ok (MINUS, <MODE>mode, operands)
+   && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (reg:CC FLAGS_REG)
+	(compare:CC (match_dup 3) (const_int 1)))
+   (parallel [(set (match_dup 0)
+		   (minus:SWI
+		     (minus:SWI (match_dup 1)
+				(ltu:SWI (reg:CC FLAGS_REG) (const_int 0)))
+		     (match_dup 2)))
+	      (clobber (reg:CC FLAGS_REG))])])
+
+(define_insn_and_split "*sub<mode>3_ne"
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+	(plus:SWI
+	  (minus:SWI
+	    (match_operand:SWI 1 "nonimmediate_operand")
+	    (ne:SWI (match_operand 3 "int_nonimmediate_operand")
+		    (const_int 0)))
+	  (match_operand:SWI 2 "<immediate_operand>")))
+   (clobber (reg:CC FLAGS_REG))]
+  "CONST_INT_P (operands[2])
+   && (<MODE>mode != DImode
+       || INTVAL (operands[2]) != HOST_WIDE_INT_C (-0x80000000))
+   && ix86_binary_operator_ok (MINUS, <MODE>mode, operands)
+   && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (reg:CC FLAGS_REG)
+	(compare:CC (match_dup 3) (const_int 1)))
+   (parallel [(set (match_dup 0)
+		   (plus:SWI
+		     (plus:SWI (ltu:SWI (reg:CC FLAGS_REG) (const_int 0))
+			       (match_dup 1))
+		     (match_dup 2)))
+	      (clobber (reg:CC FLAGS_REG))])]
+{
+  operands[2] = gen_int_mode (INTVAL (operands[2]) - 1,
+			      <MODE>mode == DImode ? SImode : <MODE>mode);
+})
+
+(define_insn_and_split "*sub<mode>3_eq_1"
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+	(plus:SWI
+	  (minus:SWI
+	    (match_operand:SWI 1 "nonimmediate_operand")
+	    (eq:SWI (match_operand 3 "int_nonimmediate_operand")
+		    (const_int 0)))
+	  (match_operand:SWI 2 "<immediate_operand>")))
+   (clobber (reg:CC FLAGS_REG))]
+  "CONST_INT_P (operands[2])
+   && (<MODE>mode != DImode
+       || INTVAL (operands[2]) != HOST_WIDE_INT_C (-0x80000000))
+   && ix86_binary_operator_ok (MINUS, <MODE>mode, operands)
+   && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (reg:CC FLAGS_REG)
+	(compare:CC (match_dup 3) (const_int 1)))
+   (parallel [(set (match_dup 0)
+		   (minus:SWI
+		     (minus:SWI (match_dup 1)
+				(ltu:SWI (reg:CC FLAGS_REG) (const_int 0)))
+		     (match_dup 2)))
+	      (clobber (reg:CC FLAGS_REG))])]
+{
+  operands[2] = gen_int_mode (-INTVAL (operands[2]),
+			      <MODE>mode == DImode ? SImode : <MODE>mode);
+})
+
+(define_insn_and_split "*sub<mode>3_eq_0"
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+	(minus:SWI
+	  (match_operand:SWI 1 "<general_operand>")
+	  (eq:SWI (match_operand 2 "int_nonimmediate_operand") (const_int 0))))
+   (clobber (reg:CC FLAGS_REG))]
+  "ix86_unary_operator_ok (MINUS, <MODE>mode, operands)
+   && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (reg:CC FLAGS_REG)
+	(compare:CC (match_dup 2) (const_int 1)))
+   (parallel [(set (match_dup 0)
+		   (minus:SWI (match_dup 1)
+			      (ltu:SWI (reg:CC FLAGS_REG) (const_int 0))))
+	      (clobber (reg:CC FLAGS_REG))])]
+{
+  if (!nonimmediate_operand (operands[1], <MODE>mode))
+    operands[1] = force_reg (<MODE>mode, operands[1]);
+})
+
+(define_insn_and_split "*sub<mode>3_ne_0"
+  [(set (match_operand:SWI 0 "nonimmediate_operand")
+	(minus:SWI
+	  (match_operand:SWI 1 "<general_operand>")
+	  (ne:SWI (match_operand 2 "int_nonimmediate_operand") (const_int 0))))
+   (clobber (reg:CC FLAGS_REG))]
+  "ix86_unary_operator_ok (MINUS, <MODE>mode, operands)
+   && can_create_pseudo_p ()"
+  "#"
+  "&& 1"
+  [(set (reg:CC FLAGS_REG)
+	(compare:CC (match_dup 2) (const_int 1)))
+   (parallel [(set (match_dup 0)
+		   (plus:SWI (plus:SWI
+			       (ltu:SWI (reg:CC FLAGS_REG) (const_int 0))
+			       (match_dup 1))
+			     (const_int -1)))
+	      (clobber (reg:CC FLAGS_REG))])]
+{
+  if (!nonimmediate_operand (operands[1], <MODE>mode))
+    operands[1] = force_reg (<MODE>mode, operands[1]);
+})
+
 ;; The patterns that match these are at the end of this file.
 
 (define_expand "<plusminus_insn>xf3"
diff --git a/gcc/config/i386/predicates.md b/gcc/config/i386/predicates.md
index 31f1cea..279827f 100644
--- a/gcc/config/i386/predicates.md
+++ b/gcc/config/i386/predicates.md
@@ -100,6 +100,15 @@
 	    (match_test "GET_MODE (op) == SImode")
 	    (match_test "GET_MODE (op) == HImode"))))
 
+;; Match a DI, SI, HI or QImode nonimmediate_operand.
+(define_special_predicate "int_nonimmediate_operand"
+  (and (match_operand 0 "nonimmediate_operand")
+       (ior (and (match_test "TARGET_64BIT")
+		 (match_test "GET_MODE (op) == DImode"))
+	    (match_test "GET_MODE (op) == SImode")
+	    (match_test "GET_MODE (op) == HImode")
+	    (match_test "GET_MODE (op) == QImode"))))
+
 ;; Match register operands, but include memory operands for TARGET_SSE_MATH.
 (define_predicate "register_ssemem_operand"
   (if_then_else
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6fc0c82..c22b137 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2019-10-19  Jakub Jelinek  <jakub@redhat.com>
+
+	PR target/92140
+	* gcc.target/i386/pr92140.c: New test.
+	* gcc.c-torture/execute/pr92140.c: New test.
+
 2019-10-19  Iain Sandoe  <iain@sandoe.co.uk>
 
 	* gcc.dg/Wnonnull.c: Add attributed function declarations for
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr92140.c b/gcc/testsuite/gcc.c-torture/execute/pr92140.c
new file mode 100644
index 0000000..1036fd8
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr92140.c
@@ -0,0 +1,83 @@
+/* PR target/92140 */
+
+char c;
+int v;
+
+__attribute__((noipa)) void f1 (void) { v += c != 0; }
+__attribute__((noipa)) void f2 (void) { v -= c != 0; }
+__attribute__((noipa)) void f3 (void) { v += c == 0; }
+__attribute__((noipa)) void f4 (void) { v -= c == 0; }
+__attribute__((noipa)) void f5 (void) { v += (c != 0) - 26; }
+__attribute__((noipa)) void f6 (void) { v -= (c != 0) - 26; }
+__attribute__((noipa)) void f7 (void) { v += (c == 0) - 26; }
+__attribute__((noipa)) void f8 (void) { v -= (c == 0) - 26; }
+__attribute__((noipa)) void f9 (void) { v += (c != 0) + 42; }
+__attribute__((noipa)) void f10 (void) { v -= (c != 0) + 42; }
+__attribute__((noipa)) void f11 (void) { v += (c == 0) + 42; }
+__attribute__((noipa)) void f12 (void) { v -= (c == 0) + 42; }
+__attribute__((noipa)) void f13 (int z) { v += (c == 0) + z; }
+__attribute__((noipa)) void f14 (int z) { v -= (c == 0) + z; }
+__attribute__((noipa)) unsigned int f15 (unsigned int n) { return n ? 2 : 1; }
+
+int
+main ()
+{
+  int i;
+  for (i = 0; i < 2; i++)
+    {
+      v = 15;
+      if (i == 1)
+	c = 37;
+      f1 ();
+      if (v != 15 + i)
+	__builtin_abort ();
+      f2 ();
+      if (v != 15)
+	__builtin_abort ();
+      f3 ();
+      if (v != 16 - i)
+	__builtin_abort ();
+      f4 ();
+      if (v != 15)
+	__builtin_abort ();
+      f5 ();
+      if (v != 15 + i - 26)
+	__builtin_abort ();
+      f6 ();
+      if (v != 15)
+	__builtin_abort ();
+      f7 ();
+      if (v != 16 - i - 26)
+	__builtin_abort ();
+      f8 ();
+      if (v != 15)
+	__builtin_abort ();
+      f9 ();
+      if (v != 15 + i + 42)
+	__builtin_abort ();
+      f10 ();
+      if (v != 15)
+	__builtin_abort ();
+      f11 ();
+      if (v != 16 - i + 42)
+	__builtin_abort ();
+      f12 ();
+      if (v != 15)
+	__builtin_abort ();
+      f13 (173);
+      if (v != 16 - i + 173)
+	__builtin_abort ();
+      f14 (173);
+      if (v != 15)
+	__builtin_abort ();
+      f13 (-35);
+      if (v != 16 - i - 35)
+	__builtin_abort ();
+      f14 (-35);
+      if (v != 15)
+	__builtin_abort ();
+    }
+  if (f15 (0) != 1 || f15 (1) != 2 || f15 (371) != 2)
+    __builtin_abort ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.target/i386/pr92140.c b/gcc/testsuite/gcc.target/i386/pr92140.c
new file mode 100644
index 0000000..f21544e
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr92140.c
@@ -0,0 +1,38 @@
+/* PR target/92140 */
+/* { dg-do compile { target nonpic } } */
+/* { dg-options "-O2 -mtune=generic -masm=att" } */
+/* { dg-additional-options "-mregparm=1" { target ia32 } } */
+/* { dg-final { scan-assembler-times "\tsbbl\t\\\$-1, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tadcl\t\\\$-1, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tadcl\t\\\$0, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tsbbl\t\\\$0, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tsbbl\t\\\$25, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tadcl\t\\\$25, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tadcl\t\\\$-26, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tsbbl\t\\\$-26, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tsbbl\t\\\$-43, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tadcl\t\\\$-43, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tadcl\t\\\$42, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tsbbl\t\\\$42, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tadcl\t%\[a-z0-9]*, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tsbbl\t%\[a-z0-9]*, v" 1 } } */
+/* { dg-final { scan-assembler-times "\tsbbl\t\\\$-1, %" 1 } } */
+
+char c;
+int v;
+
+__attribute__((noipa)) void f1 (void) { v += c != 0; }
+__attribute__((noipa)) void f2 (void) { v -= c != 0; }
+__attribute__((noipa)) void f3 (void) { v += c == 0; }
+__attribute__((noipa)) void f4 (void) { v -= c == 0; }
+__attribute__((noipa)) void f5 (void) { v += (c != 0) - 26; }
+__attribute__((noipa)) void f6 (void) { v -= (c != 0) - 26; }
+__attribute__((noipa)) void f7 (void) { v += (c == 0) - 26; }
+__attribute__((noipa)) void f8 (void) { v -= (c == 0) - 26; }
+__attribute__((noipa)) void f9 (void) { v += (c != 0) + 42; }
+__attribute__((noipa)) void f10 (void) { v -= (c != 0) + 42; }
+__attribute__((noipa)) void f11 (void) { v += (c == 0) + 42; }
+__attribute__((noipa)) void f12 (void) { v -= (c == 0) + 42; }
+__attribute__((noipa)) void f13 (int z) { v += (c == 0) + z; }
+__attribute__((noipa)) void f14 (int z) { v -= (c == 0) + z; }
+__attribute__((noipa)) unsigned int f15 (unsigned int n) { return n ? 2 : 1; }