libdw: Support DW_OP_addrx/constx and split DWARF addrx/constx support.

DW_OP_addrx/constx and GNU DebugFission DW_OP_GNU_addr/const_index take
as argument an index into the .debug_addr section for the associated CU.
This index gets resolved through dwarf_getlocation_attr. A new fake addr
CU is created per Dwarf for use with this new attribute. For split DWARF
files, the IDX_debug_addr gets replaced with the skeleton section and the
addr base is resolved immediately when constructing the split DWARF CU.
Move __libdw_cu_addr_base to libdwP.h to share with eu-readelf. Also
make it possible to resolve addrx[1234]/GNU_addr_index also as constant
indexes to (also) show when displaying these attributes in eu-readelf.

A new varlocs tests is added to test the resolving for both the DWARF4
and DWARF5 DW_OP variants. And now that addrx forms are resolved in
split DWARF files add the new DIEs with "single ranges" (those DIEs that
have a lowpc/highpc attribute pair) to run-all-dwarf-ranges.sh.

Signed-off-by: Mark Wielaard <[email protected]>

9 files changed, 299 insertions, 14 deletions

diff --git a/tests/ChangeLog b/tests/ChangeLog
index a93b0e98..2f92cc2f 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,17 @@
+2018-05-21  Mark Wielaard  <[email protected]>
+
+	* addrx_constx-4.dwo.bz2: New testfile.
+	* addrx_constx-5.dwo.bz2: Likewise.
+	* testfile-addrx_constx-4.bz2: Likewise.
+	* testfile-addrx_constx-5.bz2: Likewise
+	* Makefile.am (EXTRA_DIST): Add addrx_constx-5.dwo.bz2
+	testfile-addrx_constx-4\ .bz2 testfile-addrx_constx-5.bz2.
+	* run-varlocs.sh: Add addrx_constx tests for DWARF4 and DWARF5.
+	* varlocx.c (print_expr): Handle DW_OP_GNU_addr_index,
+	DW_OP_addrx, DW_OP_GNU_const_index and DW_OP_constx.
+	(main): Handle split DWARF.
+	* run-all-dwarf-ranges.sh: Add new ranges for addrx low/highpc.
+
 2018-05-20  Mark Wielaard  <[email protected]>
 
 	* unit-info.c: New test.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 9beae140..4b13be27 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -305,6 +305,8 @@ EXTRA_DIST = run-arextract.sh run-arsymtest.sh run-ar.sh \
 	     testfile_entry_value.c testfile_entry_value.bz2 \
 	     testfile_implicit_value.c testfile_implicit_value.bz2 \
 	     testfile_aarch64_core.bz2 testfile_i686_core.bz2 \
+	     addrx_constx-4.dwo.bz2 addrx_constx-5.dwo.bz2 \
+	     testfile-addrx_constx-4.bz2 testfile-addrx_constx-5.bz2 \
 	     run-funcretval.sh funcretval_test.c funcretval_test_aarch64.bz2 \
 	     run-backtrace-data.sh run-backtrace-dwarf.sh cleanup-13.c \
 	     run-backtrace-native.sh run-backtrace-native-biarch.sh \
diff --git a/tests/addrx_constx-4.dwo.bz2 b/tests/addrx_constx-4.dwo.bz2
new file mode 100644
index 00000000..f0bae1cd
--- /dev/null
+++ b/tests/addrx_constx-4.dwo.bz2
diff --git a/tests/addrx_constx-5.dwo.bz2 b/tests/addrx_constx-5.dwo.bz2
new file mode 100644
index 00000000..a5f4b1a6
--- /dev/null
+++ b/tests/addrx_constx-5.dwo.bz2
diff --git a/tests/run-all-dwarf-ranges.sh b/tests/run-all-dwarf-ranges.sh
index ba5528d2..ad5e634f 100755
--- a/tests/run-all-dwarf-ranges.sh
+++ b/tests/run-all-dwarf-ranges.sh
@@ -33,9 +33,30 @@ die: hello.c (11)
  4004e0..4004ff
  4003e0..4003f7
 
+die: no_say (2e)
+ 4004f0..4004ff
+
+die: main (2e)
+ 4003e0..4003f7
+
+die: subject (1d)
+ 4003e3..4003ef
+
+die: subject (2e)
+ 4004e0..4004f0
+
 die: world.c (11)
  400500..400567
 
+die: no_main (2e)
+ 400550..400567
+
+die: no_subject (1d)
+ 400553..40055f
+
+die: say (2e)
+ 400500..400540
+
 die: happy (1d)
  40051c..400526
  400530..400534
@@ -45,6 +66,9 @@ die: sad (1d)
  40051c..400526
  400535..40053f
 
+die: no_subject (2e)
+ 400540..400550
+
 EOF
 
 exit 0
diff --git a/tests/run-varlocs.sh b/tests/run-varlocs.sh
index 9c4b313e..2781fef4 100755
--- a/tests/run-varlocs.sh
+++ b/tests/run-varlocs.sh
@@ -125,4 +125,212 @@ module 'testfile_implicit_pointer'
 EOF
 
 
+# DW_OP_addrx and DW_OP_constx testcases.
+#
+# int i, j, k;
+# __thread int l, m, n;
+#
+# int main ()
+# {
+#   int r1 = i + j + k;
+#   int r2 = l + m + n;
+#   int res = r1 + r2;
+#
+#   return res;
+# }
+#
+# gcc -O2 -gdwarf-5 -gsplit-dwarf -o addrx_constx-5.o -c addrx_constx.c
+# gcc -O2 -gdwarf-5 -gsplit-dwarf -o testfile-addrx_constx-5 addrx_constx-5.o
+# gcc -O2 -gdwarf-4 -gsplit-dwarf -o addrx_constx-4.o -c addrx_constx.c
+# gcc -O2 -gdwarf-4 -gsplit-dwarf -o testfile-addrx_constx-4 addrx_constx-4.o
+
+testfiles testfile-addrx_constx-5 addrx_constx-5.dwo
+testrun_compare ${abs_top_builddir}/tests/varlocs --exprlocs -e testfile-addrx_constx-5 <<\EOF
+module 'testfile-addrx_constx-5'
+[14] CU 'addrx_constx.c'
+  producer (strx)
+  language (data1)
+  name (strx)
+  comp_dir (strx)
+  [19] variable "i"
+    name (string)
+    decl_file (implicit_const)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {addr: 0x404038}
+  [25] base_type "int"
+    byte_size (data1)
+    encoding (data1)
+    name (string)
+  [2c] variable "j"
+    name (string)
+    decl_file (implicit_const)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {addr: 0x404034}
+  [38] variable "k"
+    name (string)
+    decl_file (implicit_const)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {addr: 0x40403c}
+  [44] variable "l"
+    name (string)
+    decl_file (implicit_const)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {const: 0x403e10, form_tls_address}
+  [51] variable "m"
+    name (string)
+    decl_file (implicit_const)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {const: 0x403e0c, form_tls_address}
+  [5e] variable "n"
+    name (string)
+    decl_file (implicit_const)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {const: 0x403e08, form_tls_address}
+  [6b] subprogram "main"
+    external (flag_present)
+    name (strx)
+    decl_file (data1)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    low_pc (addrx)
+    high_pc (data8)
+    frame_base (exprloc) {call_frame_cfa {bregx(7,8)}}
+    call_all_calls (flag_present)
+    [7f] variable "r1"
+      name (string)
+      decl_file (implicit_const)
+      decl_line (data1)
+      decl_column (implicit_const)
+      type (ref4)
+      location (exprloc) {addr: 0x404038, deref_size(4), addr: 0x404034, deref_size(4), plus, addr: 0x40403c, deref_size(4), plus, stack_value}
+    [98] variable "r2"
+      name (string)
+      decl_file (implicit_const)
+      decl_line (data1)
+      decl_column (implicit_const)
+      type (ref4)
+      location (exprloc) {form_tls_address, const: 0x403e10, deref_size(4), form_tls_address, const: 0x403e0c, deref_size(4), plus, form_tls_address, const: 0x403e08, deref_size(4), plus, stack_value}
+    [b4] variable "res"
+      name (string)
+      decl_file (implicit_const)
+      decl_line (data1)
+      decl_column (implicit_const)
+      type (ref4)
+      location (exprloc) {addr: 0x404038, deref_size(4), form_tls_address, const: 0x403e08, deref_size(4), plus, form_tls_address, const: 0x403e0c, deref_size(4), plus, form_tls_address, const: 0x403e10, deref_size(4), plus, addr: 0x404034, deref_size(4), plus, addr: 0x40403c, deref_size(4), plus, stack_value}
+EOF
+
+testfiles testfile-addrx_constx-4 addrx_constx-4.dwo
+testrun_compare ${abs_top_builddir}/tests/varlocs --exprlocs -e testfile-addrx_constx-4 <<\EOF
+module 'testfile-addrx_constx-4'
+[b] CU 'addrx_constx.c'
+  producer (GNU_str_index)
+  language (data1)
+  name (GNU_str_index)
+  comp_dir (GNU_str_index)
+  GNU_dwo_id (data8)
+  [18] variable "i"
+    name (string)
+    decl_file (data1)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {addr: 0x404038}
+  [25] base_type "int"
+    byte_size (data1)
+    encoding (data1)
+    name (string)
+  [2c] variable "j"
+    name (string)
+    decl_file (data1)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {addr: 0x404034}
+  [39] variable "k"
+    name (string)
+    decl_file (data1)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {addr: 0x40403c}
+  [46] variable "l"
+    name (string)
+    decl_file (data1)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {const: 0x403e10, GNU_push_tls_address}
+  [54] variable "m"
+    name (string)
+    decl_file (data1)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {const: 0x403e0c, GNU_push_tls_address}
+  [62] variable "n"
+    name (string)
+    decl_file (data1)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    external (flag_present)
+    location (exprloc) {const: 0x403e08, GNU_push_tls_address}
+  [70] subprogram "main"
+    external (flag_present)
+    name (GNU_str_index)
+    decl_file (data1)
+    decl_line (data1)
+    decl_column (data1)
+    type (ref4)
+    low_pc (GNU_addr_index)
+    high_pc (data8)
+    frame_base (exprloc) {call_frame_cfa {bregx(7,8)}}
+    GNU_all_call_sites (flag_present)
+    [84] variable "r1"
+      name (string)
+      decl_file (data1)
+      decl_line (data1)
+      decl_column (data1)
+      type (ref4)
+      location (exprloc) {addr: 0x404038, deref_size(4), addr: 0x404034, deref_size(4), plus, addr: 0x40403c, deref_size(4), plus, stack_value}
+    [9f] variable "r2"
+      name (string)
+      decl_file (data1)
+      decl_line (data1)
+      decl_column (data1)
+      type (ref4)
+      location (exprloc) {GNU_push_tls_address, const: 0x403e10, deref_size(4), GNU_push_tls_address, const: 0x403e0c, deref_size(4), plus, GNU_push_tls_address, const: 0x403e08, deref_size(4), plus, stack_value}
+    [bd] variable "res"
+      name (string)
+      decl_file (data1)
+      decl_line (data1)
+      decl_column (data1)
+      type (ref4)
+      location (exprloc) {addr: 0x404038, deref_size(4), GNU_push_tls_address, const: 0x403e08, deref_size(4), plus, GNU_push_tls_address, const: 0x403e0c, deref_size(4), plus, GNU_push_tls_address, const: 0x403e10, deref_size(4), plus, addr: 0x404034, deref_size(4), plus, addr: 0x40403c, deref_size(4), plus, stack_value}
+EOF
+
 exit 0
diff --git a/tests/testfile-addrx_constx-4.bz2 b/tests/testfile-addrx_constx-4.bz2
new file mode 100755
index 00000000..cf10fbb1
--- /dev/null
+++ b/tests/testfile-addrx_constx-4.bz2
diff --git a/tests/testfile-addrx_constx-5.bz2 b/tests/testfile-addrx_constx-5.bz2
new file mode 100755
index 00000000..eb2a1f17
--- /dev/null
+++ b/tests/testfile-addrx_constx-5.bz2
diff --git a/tests/varlocs.c b/tests/varlocs.c
index b2ceda2e..859068d6 100644
--- a/tests/varlocs.c
+++ b/tests/varlocs.c
@@ -652,6 +652,42 @@ print_expr (Dwarf_Attribute *attr, Dwarf_Op *expr, Dwarf_Addr addr)
       }
       break;
 
+    case DW_OP_GNU_addr_index:
+    case DW_OP_addrx:
+      /* Address from the .debug_addr section (indexed based on CU).  */
+      {
+	Dwarf_Attribute addr_attr;
+	if (dwarf_getlocation_attr (attr, expr, &addr_attr) != 0)
+	  error (EXIT_FAILURE, 0, "dwarf_getlocation_attr for addr: %s",
+		 dwarf_errmsg (-1));
+
+	Dwarf_Addr address;
+	if (dwarf_formaddr (&addr_attr, &address) != 0)
+	  error (EXIT_FAILURE, 0, "dwarf_formaddr address failed: %s",
+		 dwarf_errmsg (-1));
+
+	printf ("addr: 0x%" PRIx64, address);
+      }
+      break;
+
+    case DW_OP_GNU_const_index:
+    case DW_OP_constx:
+      /* Constant from the .debug_addr section (indexed based on CU).  */
+      {
+	Dwarf_Attribute addr_attr;
+	if (dwarf_getlocation_attr (attr, expr, &addr_attr) != 0)
+	  error (EXIT_FAILURE, 0, "dwarf_getlocation_attr for addr: %s",
+		 dwarf_errmsg (-1));
+
+	Dwarf_Word constant;
+	if (dwarf_formudata (&addr_attr, &constant) != 0)
+	  error (EXIT_FAILURE, 0, "dwarf_formudata constant failed: %s",
+		 dwarf_errmsg (-1));
+
+	printf ("const: 0x%" PRIx64, constant);
+      }
+      break;
+
     default:
       error (EXIT_FAILURE, 0, "unhandled opcode: DW_OP_%s (0x%x)",
 	     opname, atom);
@@ -1019,9 +1055,18 @@ main (int argc, char *argv[])
       /* Only walk actual compile units (not partial units) that
 	 contain code if we are only interested in the function variable
 	 locations.  */
+      Dwarf_Die cudie;
+      Dwarf_Die subdie;
+      uint8_t unit_type;
+      if (dwarf_cu_info (cu->cu, NULL, &unit_type, &cudie, &subdie,
+		         NULL, NULL, NULL) != 0)
+	error (EXIT_FAILURE, 0, "dwarf_cu_info: %s", dwarf_errmsg (-1));
+      if (unit_type == DW_UT_skeleton)
+	cudie = subdie;
+
       Dwarf_Addr cubase;
-      if (dwarf_tag (cu) == DW_TAG_compile_unit
-	  && (exprlocs || dwarf_lowpc (cu, &cubase) == 0))
+      if (dwarf_tag (&cudie) == DW_TAG_compile_unit
+	  && (exprlocs || dwarf_lowpc (&cudie, &cubase) == 0))
 	{
 	  found_cu = true;
 
@@ -1043,7 +1088,7 @@ main (int argc, char *argv[])
 			      ? modname
 			      :  basename (mainfile));
 	  printf ("module '%s'\n", name);
-	  print_die (cu, "CU", 0);
+	  print_die (&cudie, "CU", 0);
 
 	  Dwarf_Addr elfbias;
 	  Elf *elf = dwfl_module_getelf (mod, &elfbias);
@@ -1060,18 +1105,10 @@ main (int argc, char *argv[])
 	  GElf_Ehdr ehdr_mem, *ehdr = gelf_getehdr (elf, &ehdr_mem);
 	  is_ET_REL = ehdr->e_type == ET_REL;
 
-	  // Get the actual CU DIE and walk all all DIEs (or just the
-	  // functions) inside it.
-	  Dwarf_Die cudie;
-	  uint8_t offsize;
-	  uint8_t addrsize;
-	  if (dwarf_diecu (cu, &cudie, &addrsize, &offsize) == NULL)
-	    error (EXIT_FAILURE, 0, "dwarf_diecu %s", dwarf_errmsg (-1));
-
 	  if (exprlocs)
 	    {
 	      Dwarf_Addr entrypc;
-	      if (dwarf_entrypc (cu, &entrypc) != 0)
+	      if (dwarf_entrypc (&cudie, &entrypc) != 0)
 		entrypc = 0;
 
 	      /* XXX - Passing true for has_frame_base is not really true.
@@ -1079,9 +1116,9 @@ main (int argc, char *argv[])
 		 attributes. Technically we should check that the DIE
 		 (types) are referenced from variables that are defined in
 		 a context (function) that has a frame base.  */
-	      handle_die (cu, 0, true /* Should be false */, entrypc);
+	      handle_die (&cudie, 0, true /* Should be false */, entrypc);
 	    }
-	  else if (dwarf_getfuncs (cu, handle_function, NULL, 0) != 0)
+	  else if (dwarf_getfuncs (&cudie, handle_function, NULL, 0) != 0)
 	    error (EXIT_FAILURE, 0, "dwarf_getfuncs %s",
 		   dwarf_errmsg (-1));
 	}