add patch fixing gcc pr93402 (wrong codegen)

affects all gcc versions 6.x and later. same patch works for all.

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93402

patches/gcc-6.5.0/0023-pr93402.diff

@@ -0,0 +1,45 @@
+2020-01-23  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/93402
+	* postreload.c (reload_combine_recognize_pattern): Don't try to adjust
+	USE insns.
+
+	* gcc.c-torture/execute/pr93402.c: New test.
+
+--- a/gcc/postreload.c.jj	2020-01-12 11:54:36.000000000 +0100
++++ b/gcc/postreload.c	2020-01-23 17:23:25.359929516 +0100
+@@ -1078,6 +1078,10 @@ reload_combine_recognize_pattern (rtx_in
+       struct reg_use *use = reg_state[regno].reg_use + i;
+       if (GET_MODE (*use->usep) != mode)
+ 	return false;
++      /* Don't try to adjust (use (REGX)).  */
++      if (GET_CODE (PATTERN (use->insn)) == USE
++	  && &XEXP (PATTERN (use->insn), 0) == use->usep)
++	return false;
+     }
+ 
+   /* Look for (set (REGX) (CONST_INT))
+--- a/gcc/testsuite/gcc.c-torture/execute/pr93402.c.jj	2020-01-23 17:25:46.496803852 +0100
++++ b/gcc/testsuite/gcc.c-torture/execute/pr93402.c	2020-01-23 17:25:05.221425501 +0100
+@@ -0,0 +1,21 @@
++/* PR rtl-optimization/93402 */
++
++struct S { unsigned int a; unsigned long long b; };
++
++__attribute__((noipa)) struct S
++foo (unsigned long long x)
++{
++  struct S ret;
++  ret.a = 0;
++  ret.b = x * 11111111111ULL + 111111111111ULL;
++  return ret;
++}
++
++int
++main ()
++{
++  struct S a = foo (1);
++  if (a.a != 0 || a.b != 122222222222ULL)
++    __builtin_abort ();
++  return 0;
++}

patches/gcc-7.3.0/0020-pr93402.diff

@@ -0,0 +1,45 @@
+2020-01-23  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/93402
+	* postreload.c (reload_combine_recognize_pattern): Don't try to adjust
+	USE insns.
+
+	* gcc.c-torture/execute/pr93402.c: New test.
+
+--- a/gcc/postreload.c.jj	2020-01-12 11:54:36.000000000 +0100
++++ b/gcc/postreload.c	2020-01-23 17:23:25.359929516 +0100
+@@ -1078,6 +1078,10 @@ reload_combine_recognize_pattern (rtx_in
+       struct reg_use *use = reg_state[regno].reg_use + i;
+       if (GET_MODE (*use->usep) != mode)
+ 	return false;
++      /* Don't try to adjust (use (REGX)).  */
++      if (GET_CODE (PATTERN (use->insn)) == USE
++	  && &XEXP (PATTERN (use->insn), 0) == use->usep)
++	return false;
+     }
+ 
+   /* Look for (set (REGX) (CONST_INT))
+--- a/gcc/testsuite/gcc.c-torture/execute/pr93402.c.jj	2020-01-23 17:25:46.496803852 +0100
++++ b/gcc/testsuite/gcc.c-torture/execute/pr93402.c	2020-01-23 17:25:05.221425501 +0100
+@@ -0,0 +1,21 @@
++/* PR rtl-optimization/93402 */
++
++struct S { unsigned int a; unsigned long long b; };
++
++__attribute__((noipa)) struct S
++foo (unsigned long long x)
++{
++  struct S ret;
++  ret.a = 0;
++  ret.b = x * 11111111111ULL + 111111111111ULL;
++  return ret;
++}
++
++int
++main ()
++{
++  struct S a = foo (1);
++  if (a.a != 0 || a.b != 122222222222ULL)
++    __builtin_abort ();
++  return 0;
++}

patches/gcc-8.3.0/0017-pr93402.diff

@@ -0,0 +1,45 @@
+2020-01-23  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/93402
+	* postreload.c (reload_combine_recognize_pattern): Don't try to adjust
+	USE insns.
+
+	* gcc.c-torture/execute/pr93402.c: New test.
+
+--- a/gcc/postreload.c.jj	2020-01-12 11:54:36.000000000 +0100
++++ b/gcc/postreload.c	2020-01-23 17:23:25.359929516 +0100
+@@ -1078,6 +1078,10 @@ reload_combine_recognize_pattern (rtx_in
+       struct reg_use *use = reg_state[regno].reg_use + i;
+       if (GET_MODE (*use->usep) != mode)
+ 	return false;
++      /* Don't try to adjust (use (REGX)).  */
++      if (GET_CODE (PATTERN (use->insn)) == USE
++	  && &XEXP (PATTERN (use->insn), 0) == use->usep)
++	return false;
+     }
+ 
+   /* Look for (set (REGX) (CONST_INT))
+--- a/gcc/testsuite/gcc.c-torture/execute/pr93402.c.jj	2020-01-23 17:25:46.496803852 +0100
++++ b/gcc/testsuite/gcc.c-torture/execute/pr93402.c	2020-01-23 17:25:05.221425501 +0100
+@@ -0,0 +1,21 @@
++/* PR rtl-optimization/93402 */
++
++struct S { unsigned int a; unsigned long long b; };
++
++__attribute__((noipa)) struct S
++foo (unsigned long long x)
++{
++  struct S ret;
++  ret.a = 0;
++  ret.b = x * 11111111111ULL + 111111111111ULL;
++  return ret;
++}
++
++int
++main ()
++{
++  struct S a = foo (1);
++  if (a.a != 0 || a.b != 122222222222ULL)
++    __builtin_abort ();
++  return 0;
++}

patches/gcc-9.2.0/0017-pr93402.diff

@@ -0,0 +1,45 @@
+2020-01-23  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/93402
+	* postreload.c (reload_combine_recognize_pattern): Don't try to adjust
+	USE insns.
+
+	* gcc.c-torture/execute/pr93402.c: New test.
+
+--- a/gcc/postreload.c.jj	2020-01-12 11:54:36.000000000 +0100
++++ b/gcc/postreload.c	2020-01-23 17:23:25.359929516 +0100
+@@ -1078,6 +1078,10 @@ reload_combine_recognize_pattern (rtx_in
+       struct reg_use *use = reg_state[regno].reg_use + i;
+       if (GET_MODE (*use->usep) != mode)
+ 	return false;
++      /* Don't try to adjust (use (REGX)).  */
++      if (GET_CODE (PATTERN (use->insn)) == USE
++	  && &XEXP (PATTERN (use->insn), 0) == use->usep)
++	return false;
+     }
+ 
+   /* Look for (set (REGX) (CONST_INT))
+--- a/gcc/testsuite/gcc.c-torture/execute/pr93402.c.jj	2020-01-23 17:25:46.496803852 +0100
++++ b/gcc/testsuite/gcc.c-torture/execute/pr93402.c	2020-01-23 17:25:05.221425501 +0100
+@@ -0,0 +1,21 @@
++/* PR rtl-optimization/93402 */
++
++struct S { unsigned int a; unsigned long long b; };
++
++__attribute__((noipa)) struct S
++foo (unsigned long long x)
++{
++  struct S ret;
++  ret.a = 0;
++  ret.b = x * 11111111111ULL + 111111111111ULL;
++  return ret;
++}
++
++int
++main ()
++{
++  struct S a = foo (1);
++  if (a.a != 0 || a.b != 122222222222ULL)
++    __builtin_abort ();
++  return 0;
++}