gdb: Better support for dynamic properties with negative values

When the type of a property is smaller than the CORE_ADDR in which the
property value has been placed, and if the property is signed, then
sign extend the property value from its actual type up to the size of
CORE_ADDR.

gdb/ChangeLog:

	* dwarf2loc.c (dwarf2_evaluate_property): Sign extend property
	value if its desired type is smaller than a CORE_ADDR and signed.

gdb/testsuite/ChangeLog:

	* gdb.fortran/vla-ptype.exp: Print array with negative bounds.
	* gdb.fortran/vla-sizeof.exp: Print the size of an array with
	negative bounds.
	* gdb.fortran/vla-value.exp: Print elements of an array with
	negative bounds.
	* gdb.fortran/vla.f90: Setup an array with negative bounds for
	testing.

7 files changed, 103 insertions, 0 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index d2dec79..d79d89f 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,10 @@
 2019-07-12  Andrew Burgess  <andrew.burgess@embecosm.com>
 
+	* dwarf2loc.c (dwarf2_evaluate_property): Sign extend property
+	value if its desired type is smaller than a CORE_ADDR and signed.
+
+2019-07-12  Andrew Burgess  <andrew.burgess@embecosm.com>
+
 	* dwarf2loc.c (dwarf2_evaluate_property): Update to take account
 	of changes to field names, and use new is_reference field to
 	decide if a property is a reference or not.
diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c
index 00f3d76..63643cb 100644
--- a/gdb/dwarf2loc.c
+++ b/gdb/dwarf2loc.c
@@ -2454,6 +2454,29 @@ dwarf2_evaluate_property (const struct dynamic_prop *prop,
 		struct value *val = value_at (baton->property_type, *value);
 		*value = value_as_address (val);
 	      }
+	    else
+	      {
+		gdb_assert (baton->property_type != NULL);
+
+		struct type *type = check_typedef (baton->property_type);
+		if (TYPE_LENGTH (type) < sizeof (CORE_ADDR)
+		    && !TYPE_UNSIGNED (type))
+		  {
+		    /* If we have a valid return candidate and it's value
+		       is signed, we have to sign-extend the value because
+		       CORE_ADDR on 64bit machine has 8 bytes but address
+		       size of an 32bit application is bytes.  */
+		    const int addr_size
+		      = (dwarf2_per_cu_addr_size (baton->locexpr.per_cu)
+			 * TARGET_CHAR_BIT);
+		    const CORE_ADDR neg_mask
+		      = (~((CORE_ADDR) 0) <<  (addr_size - 1));
+
+		    /* Check if signed bit is set and sign-extend values.  */
+		    if (*value & neg_mask)
+		      *value |= neg_mask;
+		  }
+	      }
 	    return true;
 	  }
       }
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 238fcfc..91b90d8 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,14 @@
+2019-07-12  Bernhard Heckel  <bernhard.heckel@intel.com>
+	    Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* gdb.fortran/vla-ptype.exp: Print array with negative bounds.
+	* gdb.fortran/vla-sizeof.exp: Print the size of an array with
+	negative bounds.
+	* gdb.fortran/vla-value.exp: Print elements of an array with
+	negative bounds.
+	* gdb.fortran/vla.f90: Setup an array with negative bounds for
+	testing.
+
 2019-07-11  Andrew Burgess  <andrew.burgess@embecosm.com>
 
 	* gdb.base/options.exp (expect_string): Dequote strings in
diff --git a/gdb/testsuite/gdb.fortran/vla-ptype.exp b/gdb/testsuite/gdb.fortran/vla-ptype.exp
index a4c3c9c..7f8268b 100644
--- a/gdb/testsuite/gdb.fortran/vla-ptype.exp
+++ b/gdb/testsuite/gdb.fortran/vla-ptype.exp
@@ -98,3 +98,15 @@ gdb_test "ptype vla2" "type = $real, allocatable \\(:,:,:\\)" "ptype vla2 not al
 gdb_test "ptype vla2(5, 45, 20)" \
   "no such vector element \\\(vector not allocated\\\)" \
   "ptype vla2(5, 45, 20) not allocated"
+
+gdb_breakpoint [gdb_get_line_number "vla1-neg-bounds-v1"]
+gdb_continue_to_breakpoint "vla1-neg-bounds-v1"
+gdb_test "ptype vla1" \
+    "type = $real, allocatable \\(-2:-1,-5:-2,-3:-1\\)" \
+    "ptype vla1 negative bounds"
+
+gdb_breakpoint [gdb_get_line_number "vla1-neg-bounds-v2"]
+gdb_continue_to_breakpoint "vla1-neg-bounds-v2"
+gdb_test "ptype vla1" \
+    "type = $real, allocatable \\(-2:1,-5:2,-3:1\\)" \
+    "ptype vla1 negative lower bounds, positive upper bounds"
diff --git a/gdb/testsuite/gdb.fortran/vla-sizeof.exp b/gdb/testsuite/gdb.fortran/vla-sizeof.exp
index 4fe6938..4aece0b 100644
--- a/gdb/testsuite/gdb.fortran/vla-sizeof.exp
+++ b/gdb/testsuite/gdb.fortran/vla-sizeof.exp
@@ -59,3 +59,13 @@ gdb_test "print sizeof(pvla)" " = 4000" "print sizeof associated pvla"
 gdb_test "print sizeof(pvla(3,2,1))" "4" \
     "print sizeof element from associated pvla"
 gdb_test "print sizeof(pvla(3:4,2,1))" "800" "print sizeof sliced pvla"
+
+gdb_breakpoint [gdb_get_line_number "vla1-neg-bounds-v1"]
+gdb_continue_to_breakpoint "vla1-neg-bounds-v1"
+gdb_test "print sizeof(vla1)" " = 96" \
+    "print sizeof vla1 negative bounds"
+
+gdb_breakpoint [gdb_get_line_number "vla1-neg-bounds-v2"]
+gdb_continue_to_breakpoint "vla1-neg-bounds-v2"
+gdb_test "print sizeof(vla1)" " = 640" \
+    "print sizeof vla1 negative lower bounds, positive upper bounds"
diff --git a/gdb/testsuite/gdb.fortran/vla-value.exp b/gdb/testsuite/gdb.fortran/vla-value.exp
index 3cf5d67..ed0cace 100644
--- a/gdb/testsuite/gdb.fortran/vla-value.exp
+++ b/gdb/testsuite/gdb.fortran/vla-value.exp
@@ -161,3 +161,30 @@ gdb_breakpoint [gdb_get_line_number "pvla-deassociated"]
 gdb_continue_to_breakpoint "pvla-deassociated, second time"
 gdb_test "print \$mypvar(1,3,8)" " = 1001" \
   "print \$mypvar(1,3,8) after deallocated"
+
+gdb_breakpoint [gdb_get_line_number "vla1-neg-bounds-v1"]
+gdb_continue_to_breakpoint "vla1-neg-bounds-v1"
+with_test_prefix "negative bounds" {
+    gdb_test "print vla1(-2,-5,-3)" " = 1"
+    gdb_test "print vla1(-2,-3,-1)" " = -231"
+    gdb_test "print vla1(-3,-5,-3)" "no such vector element"
+    gdb_test "print vla1(-2,-6,-3)" "no such vector element"
+    gdb_test "print vla1(-2,-5,-4)" "no such vector element"
+    gdb_test "print vla1(0,-2,-1)" "no such vector element"
+    gdb_test "print vla1(-1,-1,-1)" "no such vector element"
+    gdb_test "print vla1(-1,-2,0)" "no such vector element"
+}
+
+gdb_breakpoint [gdb_get_line_number "vla1-neg-bounds-v2"]
+gdb_continue_to_breakpoint "vla1-neg-bounds-v2"
+with_test_prefix "negative lower bounds, positive upper bounds" {
+    gdb_test "print vla1(-2,-5,-3)" " = 2"
+    gdb_test "print vla1(-2,-3,-1)" " = 2"
+    gdb_test "print vla1(-2,-4,-2)" " = -242"
+    gdb_test "print vla1(-3,-5,-3)" "no such vector element"
+    gdb_test "print vla1(-2,-6,-3)" "no such vector element"
+    gdb_test "print vla1(-2,-5,-4)" "no such vector element"
+    gdb_test "print vla1(2,2,1)" "no such vector element"
+    gdb_test "print vla1(1,3,1)" "no such vector element"
+    gdb_test "print vla1(1,2,2)" "no such vector element"
+}
diff --git a/gdb/testsuite/gdb.fortran/vla.f90 b/gdb/testsuite/gdb.fortran/vla.f90
index 5bc6087..0ccb5c9 100644
--- a/gdb/testsuite/gdb.fortran/vla.f90
+++ b/gdb/testsuite/gdb.fortran/vla.f90
@@ -54,4 +54,19 @@ program vla
 
   allocate (vla3 (2,2))               ! vla2-deallocated
   vla3(:,:) = 13
+
+  allocate (vla1 (-2:-1, -5:-2, -3:-1))
+  vla1(:, :, :) = 1
+  vla1(-2, -3, -1) = -231
+
+  deallocate (vla1)                   ! vla1-neg-bounds-v1
+  l = allocated(vla1)
+
+  allocate (vla1 (-2:1, -5:2, -3:1))
+  vla1(:, :, :) = 2
+  vla1(-2, -4, -2) = -242
+
+  deallocate (vla1)                   ! vla1-neg-bounds-v2
+  l = allocated(vla1)
+
 end program vla