[gdb/testsuite] Use function_range in gdb.dwarf2/dw2-abs-hi-pc.exp

When I run test-case gdb.dwarf2/dw2-abs-hi-pc.exp with gcc, we have:
...
(gdb) break hello^M
Breakpoint 1 at 0x4004c0: file dw2-abs-hi-pc-hello.c, line 24.^M
(gdb) PASS: gdb.dwarf2/dw2-abs-hi-pc.exp: break hello
...
but with clang, I run into:
...
(gdb) break hello^M
Breakpoint 1 at 0x4004e4^M
(gdb) FAIL: gdb.dwarf2/dw2-abs-hi-pc.exp: break hello
...

The problem is that the CU and function both have an empty address range:
...
 <0><d2>: Abbrev Number: 1 (DW_TAG_compile_unit)
    <108>   DW_AT_name        : dw2-abs-hi-pc-hello.c
    <123>   DW_AT_low_pc      : 0x4004e0
    <127>   DW_AT_high_pc     : 0x4004e0
 <1><12f>: Abbrev Number: 2 (DW_TAG_subprogram)
    <131>   DW_AT_name        : hello
    <13a>   DW_AT_low_pc      : 0x4004e0
    <13e>   DW_AT_high_pc     : 0x4004e0
...

The address ranges are set like this in dw2-abs-hi-pc-hello-dbg.S:
...
        .4byte  .hello_start    /* DW_AT_low_pc */
        .4byte  .hello_end      /* DW_AT_high_pc */
...
where the labels refer to dw2-abs-hi-pc-hello.c:
...
extern int v;

asm (".hello_start: .globl .hello_start\n");
void
hello (void)
{
asm (".hello0: .globl .hello0\n");
  v++;
asm (".hello1: .globl .hello1\n");
}
asm (".hello_end: .globl .hello_end\n");
...

Using asm labels in global scope is a known source of problems, as explained
in the comment of proc function_range in gdb/testsuite/lib/dwarf.exp.

Fix this by using function_range instead.

Tested on x86_64-linux with gcc and clang-7 and clang-12.

5 files changed, 41 insertions, 18 deletions

diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S
index bfe3889..8f7103d 100644
--- a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello-dbg.S
@@ -24,8 +24,8 @@
 	.byte	0x1	/* DW_AT_language */
 	.ascii	"dw2-abs-hi-pc-hello.c\0"     /* DW_AT_name */
 	.ascii  "/tmp\0"        /* DW_AT_comp_dir */
-	.4byte	.hello_start	/* DW_AT_low_pc */
-	.4byte	.hello_end	/* DW_AT_high_pc */
+	.4byte	HELLO_START	/* DW_AT_low_pc */
+	.4byte	HELLO_END	/* DW_AT_high_pc */
 	.4byte	.Ldebug_line0	/* DW_AT_stmt_list */
 	.uleb128 0x2	/* (DIE (0x2d) DW_TAG_subprogram) */
 	.byte	0x1	/* DW_AT_external */
@@ -33,8 +33,8 @@
 	.byte	0x1	/* DW_AT_decl_file (hello.c) */
 	.byte	0x13	/* DW_AT_decl_line */
 	.byte	0x1	/* DW_AT_prototyped */
-	.4byte	.hello_start	/* DW_AT_low_pc */
-	.4byte	.hello_end	/* DW_AT_high_pc */
+	.4byte	HELLO_START	/* DW_AT_low_pc */
+	.4byte	HELLO_END	/* DW_AT_high_pc */
 	.byte	0	/* end of children of DIE 0xb */
 .Ledebug_info0:
 
@@ -114,7 +114,7 @@ LELTP:
         .byte   0        /* set address to .hello_start */
         .uleb128 0x5
         .byte   0x2
-        .4byte  .hello_start
+        .4byte  HELLO_START
         .byte   0x3      /* DW_LNS_advance_line */
         .sleb128 22      /* ... to 23 */
         .byte   0x5      /* column 0 */
@@ -144,7 +144,7 @@ LELTP:
         .byte   0        /* set address to .hello_end */
         .uleb128 0x5
         .byte   0x2
-        .4byte  .hello_end
+        .4byte  HELLO_END
         .byte   0        /* end sequence */
         .uleb128 0x1
         .byte   0x1
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello.c b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello.c
index 4d26968..ab24c9e 100644
--- a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello.c
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-hello.c
@@ -17,12 +17,11 @@
 
 extern int v;
 
-asm (".hello_start: .globl .hello_start\n");
 void
 hello (void)
 {
+asm ("hello_label: .globl hello_label\n");
 asm (".hello0: .globl .hello0\n");
   v++;
 asm (".hello1: .globl .hello1\n");
 }
-asm (".hello_end: .globl .hello_end\n");
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S
index 4e19f66..ed74c99 100644
--- a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world-dbg.S
@@ -24,8 +24,8 @@
 	.byte	0x1	/* DW_AT_language */
 	.ascii	"dw2-abs-hi-pc-world.c\0"     /* DW_AT_name */
 	.ascii  "/tmp\0"        /* DW_AT_comp_dir */
-	.4byte	.world_start	/* DW_AT_low_pc */
-	.4byte	.world_end	/* DW_AT_high_pc */
+	.4byte	WORLD_START	/* DW_AT_low_pc */
+	.4byte	WORLD_END	/* DW_AT_high_pc */
 	.4byte	.Ldebug_line0	/* DW_AT_stmt_list */
 	.uleb128 0x2	/* (DIE (0x2d) DW_TAG_subprogram) */
 	.byte	0x1	/* DW_AT_external */
@@ -33,8 +33,8 @@
 	.byte	0x1	/* DW_AT_decl_file (world.c) */
 	.byte	0x13	/* DW_AT_decl_line */
 	.byte	0x1	/* DW_AT_prototyped */
-	.4byte	.world_start	/* DW_AT_low_pc */
-	.4byte	.world_end	/* DW_AT_high_pc */
+	.4byte	WORLD_START	/* DW_AT_low_pc */
+	.4byte	WORLD_END	/* DW_AT_high_pc */
 	.byte	0	/* end of children of DIE 0xb */
 .Ledebug_info0:
 
@@ -114,7 +114,7 @@ LELTP:
         .byte   0        /* set address to .world_start */
         .uleb128 0x5
         .byte   0x2
-        .4byte  .world_start
+        .4byte  WORLD_START
         .byte   0x3      /* DW_LNS_advance_line */
         .sleb128 22      /* ... to 23 */
         .byte   0x5      /* column 0 */
@@ -144,7 +144,7 @@ LELTP:
         .byte   0        /* set address to .world_end */
         .uleb128 0x5
         .byte   0x2
-        .4byte  .world_end
+        .4byte  WORLD_END
         .byte   0        /* end sequence */
         .uleb128 0x1
         .byte   0x1
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world.c b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world.c
index 0e4a60d..d06734c 100644
--- a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world.c
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc-world.c
@@ -17,12 +17,11 @@
 
 extern int v;
 
-asm (".world_start: .globl .world_start\n");
 void
 world (void)
 {
+asm ("world_label: .globl world_label\n");
 asm (".world0: .globl .world0\n");
   v++;
 asm (".world1: .globl .world1\n");
 }
-asm (".world_end: .globl .world_end\n");
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.exp b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.exp
index 9a30b61..0bb49f1 100644
--- a/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.exp
+++ b/gdb/testsuite/gdb.dwarf2/dw2-abs-hi-pc.exp
@@ -20,9 +20,34 @@ if {![dwarf2_support]} {
 }
 
 standard_testfile
-set executable ${testfile}
 
-if {[build_executable ${testfile}.exp ${executable} "${testfile}.c ${testfile}-hello-dbg.S ${testfile}-hello.c ${testfile}-world-dbg.S ${testfile}-world.c" "nodebug"] == -1} {
+set sources \
+    [list \
+	 ${testfile}.c \
+	 ${testfile}-hello.c \
+	 ${testfile}-world.c]
+set sources [lmap i $sources { string cat "${srcdir}/${subdir}/" $i }]
+lassign [function_range hello $sources] \
+    hello_start hello_len
+lassign [function_range world $sources] \
+    world_start world_len
+
+set sources \
+    [list \
+	 ${testfile}.c \
+	 ${testfile}-hello-dbg.S \
+	 ${testfile}-hello.c \
+	 ${testfile}-world-dbg.S \
+	 ${testfile}-world.c]
+set flags \
+    [list \
+	 "nodebug" \
+	 "additional_flags=\"-DHELLO_START=$hello_start\"" \
+	 "additional_flags=\"-DHELLO_END=$hello_start + $hello_len\"" \
+	 "additional_flags=\"-DWORLD_START=$world_start\"" \
+	 "additional_flags=\"-DWORLD_END=$world_start + $world_len\""]
+set executable ${testfile}
+if {[build_executable ${testfile}.exp ${executable} $sources $flags] == -1} {
     return -1
 }