Refactor and update CTF testcases [PR105089]

This commit splits the ctf-array-2.c into ctf-array-5.c and
ctf-variables.c with the following responsibilities:

[1] ctf-array-2.c: Test CTF generation for unsized arrays.
[2] ctf-array-5.c: Test CTF generation for unsized but initialized array.
[3] ctf-variables-3.c: Test CTF generation for extern variable with defining
decl.

Earlier all three tests above were being done in ctf-array-2.c.  The
checks around [3] were very loose in the original version of ctf-array-2.c
in that the testcase was only checking that the types are as expected.  The
compiler was emitting two CTF variable records as follows:

 Variables:
  _CTF_NEWSTR ->  5: const const char [0] (size 0x0) -> 4: const char [0] (size 0x0)
  _CTF_NEWSTR ->  8: const const char [8] (size 0x8) -> 7: const char [8] (size 0x8)

This is incorrect behaviour as it creates ambiguity.  The testcase
ctf-variables-3.c now has added checks that only one CTF variable record
is expected.

2022-04-14  Indu Bhagat  <indu.bhagat@oracle.com>

gcc/testsuite/ChangeLog:

	PR debug/105089
	* gcc.dg/debug/ctf/ctf-array-2.c: Refactor testcase.  Move some
	checks ...
	* gcc.dg/debug/ctf/ctf-array-5.c: ... to here.
	* gcc.dg/debug/ctf/ctf-variables-3.c: ... and here.  Add
	additional checks for one CTF variable and one CTF object info
	record.

3 files changed, 46 insertions, 15 deletions

diff --git a/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-2.c b/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-2.c
index 2a19da0..4721c4f 100644
--- a/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-2.c
+++ b/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-2.c
@@ -5,34 +5,26 @@
 
    TBD_CTF_FORMAT_OPEN_ISSUES (1) - 
    This testcase makes a note of the case of a probable misrepresentation.
-   See Note 1 and Note 2 below.
+   See Note 1 below.
 
    In the CTF section, these types are encoded as :
 
      Variables:
-      _CTF_NEWSTR ->  7: const char [0] (size 0x0)
-      _CTF_SECTION ->  6: const char [5] (size 0x5)
-      b1 ->  2: int [0] (size 0x0)
-      b2 ->  3: int [0] (size 0x0)
+      b1 ->  3: int [0] (size 0x0)
+      b2 ->  5: int [0] (size 0x0)
 
     Note 1 : There is misrepresentation in that b1 and b2 are specified
     differently by the user.
-    Note 2 : It is arguable though whether the representation for
-    _CTF_NEWSTR is incorrect.  */
+    
+    In this testcase, two CTF array records each of type int [0] is expected.  */
 
 /* { dg-do compile )  */
 /* { dg-options "-O0 -gctf -dA" } */
 
-/* { dg-final { scan-assembler-times "0x12000000\[\t \]+\[^\n\]*ctt_info" 5 } } */
+/* { dg-final { scan-assembler-times "0x12000000\[\t \]+\[^\n\]*ctt_info" 2 } } */
 
-/* { dg-final { scan-assembler-times "\[\t \]0\[\t \]+\[^\n\]*cta_nelems" 3 } } */
-/* { dg-final { scan-assembler-times "\[\t \]0x5\[\t \]+\[^\n\]*cta_nelems" 1 } } */
+/* { dg-final { scan-assembler-times "\[\t \]0\[\t \]+\[^\n\]*cta_nelems" 2 } } */
 
 static int b1[] = {};
 
 int b2[0];
-
-const char _CTF_SECTION[] = ".ctf";
-
-extern const char _CTF_NEWSTR[];
-const char _CTF_NEWSTR[] = "ctfinfo"; 
diff --git a/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-5.c b/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-5.c
new file mode 100644
index 0000000..ec50441
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-5.c
@@ -0,0 +1,17 @@
+/* CTF generation for unsized (but initialized) arrays
+
+   In this testcase, one CTF array type record of size 5 is expected.
+
+     Variables:
+      _CTF_SECTION ->  5: const const char [5] (size 0x5) -> 4: const char [5] (size 0x5)
+
+*/
+
+/* { dg-do compile )  */
+/* { dg-options "-O0 -gctf -dA" } */
+
+/* { dg-final { scan-assembler-times "0x12000000\[\t \]+\[^\n\]*ctt_info" 1 } } */
+
+/* { dg-final { scan-assembler-times "\[\t \]0x5\[\t \]+\[^\n\]*cta_nelems" 1 } } */
+
+const char _CTF_SECTION[] = ".ctf";
diff --git a/gcc/testsuite/gcc.dg/debug/ctf/ctf-variables-3.c b/gcc/testsuite/gcc.dg/debug/ctf/ctf-variables-3.c
new file mode 100644
index 0000000..8aea1e8
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/debug/ctf/ctf-variables-3.c
@@ -0,0 +1,22 @@
+/* CTF generation for extern variable with defining and non-defining decl
+   in the same CU.
+
+   This testcase checks the case when a non-defining decl is followed by
+   a defining decl for the same variable.  See PR debug/105089.
+   
+   In this testcase,  although two CTF array types are generated, only a
+   single CTF variable and a single entry in the CTF object info section
+   are expected.  */
+
+/* { dg-do compile )  */
+/* { dg-options "-O0 -gctf -dA" } */
+
+/* { dg-final { scan-assembler-times "0x12000000\[\t \]+\[^\n\]*ctt_info" 2 } } */
+
+/* { dg-final { scan-assembler-times "\[\t \]0\[\t \]+\[^\n\]*cta_nelems" 1 } } */
+/* { dg-final { scan-assembler-times "\[\t \]0x8\[\t \]+\[^\n\]*cta_nelems" 1 } } */
+/* { dg-final { scan-assembler-times "ctv_name" 1 } } */
+/* { dg-final { scan-assembler-times "objtinfo_var_type" 1 } } */
+
+extern const char _CTF_NEWSTR[];
+const char _CTF_NEWSTR[] = "ctfinfo";