* Makefile.in (dwarf2loc.o): Update dependencies.

	* ax-gdb.c (gen_var_ref): Handle LOC_COMPUTED and LOC_COMPUTED_ARG.
	* dwarf2expr.c (read_uleb128, read_sleb128): Make non-static.
	* dwarf2expr.h (read_uleb128, read_sleb128): Add prototypes.
	* dwarf2loc.c: Include "ax.h" and "ax-gdb.h".
	(locexpr_tracepoint_var_ref): New function.
	(dwarf2_locexpr_funcs): Add locexpr_tracepoint_var_ref.

6 files changed, 89 insertions, 4 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 07f4fba809b..f40b5bf9ad1 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,13 @@
+2003-02-28  Daniel Jacobowitz  <drow@mvista.com>
+
+	* Makefile.in (dwarf2loc.o): Update dependencies.
+	* ax-gdb.c (gen_var_ref): Handle LOC_COMPUTED and LOC_COMPUTED_ARG.
+	* dwarf2expr.c (read_uleb128, read_sleb128): Make non-static.
+	* dwarf2expr.h (read_uleb128, read_sleb128): Add prototypes.
+	* dwarf2loc.c: Include "ax.h" and "ax-gdb.h".
+	(locexpr_tracepoint_var_ref): New function.
+	(dwarf2_locexpr_funcs): Add locexpr_tracepoint_var_ref.
+
 2003-02-28  Andrew Cagney  <cagney@redhat.com>
 
 	* regcache.c (register_size): New function.
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 02e160e23cb..c63f2fb69a0 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -1640,7 +1640,7 @@ dwarf2expr.o: dwarf2expr.c $(defs_h) $(symtab_h) $(gdbtypes_h) $(value_h) \
 	 $(gdbcore_h) $(dwarf2expr_h)
 dwarf2loc.o: dwarf2loc.c $(defs_h) $(ui_out_h) $(value_h) $(frame_h) \
 	$(gdbcore_h) $(target_h) $(inferior_h) $(dwarf2expr_h) \
-	$(dwarf2loc_h) $(gdb_string_h)
+	$(dwarf2loc_h) $(ax_h) $(ax_gdb_h) $(gdb_string_h)
 dwarf2read.o: dwarf2read.c $(defs_h) $(bfd_h) $(symtab_h) $(gdbtypes_h) \
 	$(symfile_h) $(objfiles_h) $(elf_dwarf2_h) $(buildsym_h) \
 	$(demangle_h) $(expression_h) $(filenames_h) $(macrotab_h) \
diff --git a/gdb/ax-gdb.c b/gdb/ax-gdb.c
index e5f3048c0bf..253636973d5 100644
--- a/gdb/ax-gdb.c
+++ b/gdb/ax-gdb.c
@@ -618,6 +618,11 @@ gen_var_ref (struct agent_expr *ax, struct axs_value *value, struct symbol *var)
       }
       break;
 
+    case LOC_COMPUTED:
+    case LOC_COMPUTED_ARG:
+      (*SYMBOL_LOCATION_FUNCS (var)->tracepoint_var_ref) (var, ax, value);
+      break;
+
     case LOC_OPTIMIZED_OUT:
       error ("The variable `%s' has been optimized out.",
 	     SYMBOL_PRINT_NAME (var));
diff --git a/gdb/dwarf2expr.c b/gdb/dwarf2expr.c
index 02e246f6d58..df6fc73ceb7 100644
--- a/gdb/dwarf2expr.c
+++ b/gdb/dwarf2expr.c
@@ -115,7 +115,7 @@ dwarf_expr_eval (struct dwarf_expr_context *ctx, unsigned char *addr,
    by R, and return the new value of BUF.  Verify that it doesn't extend
    past BUF_END.  */
 
-static unsigned char *
+unsigned char *
 read_uleb128 (unsigned char *buf, unsigned char *buf_end, ULONGEST * r)
 {
   unsigned shift = 0;
@@ -141,7 +141,7 @@ read_uleb128 (unsigned char *buf, unsigned char *buf_end, ULONGEST * r)
    by R, and return the new value of BUF.  Verify that it doesn't extend
    past BUF_END.  */
 
-static unsigned char *
+unsigned char *
 read_sleb128 (unsigned char *buf, unsigned char *buf_end, LONGEST * r)
 {
   unsigned shift = 0;
diff --git a/gdb/dwarf2expr.h b/gdb/dwarf2expr.h
index e8cc489dcf6..3d0fcb33e7b 100644
--- a/gdb/dwarf2expr.h
+++ b/gdb/dwarf2expr.h
@@ -94,4 +94,10 @@ void dwarf_expr_eval (struct dwarf_expr_context *ctx, unsigned char *addr,
 		      size_t len);
 CORE_ADDR dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n);
 
+
+unsigned char *read_uleb128 (unsigned char *buf, unsigned char *buf_end,
+			     ULONGEST * r);
+unsigned char *read_sleb128 (unsigned char *buf, unsigned char *buf_end,
+			     LONGEST * r);
+
 #endif
diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c
index 330765d556a..55de8dae74e 100644
--- a/gdb/dwarf2loc.c
+++ b/gdb/dwarf2loc.c
@@ -26,6 +26,8 @@
 #include "gdbcore.h"
 #include "target.h"
 #include "inferior.h"
+#include "ax.h"
+#include "ax-gdb.h"
 
 #include "elf/dwarf2.h"
 #include "dwarf2expr.h"
@@ -277,11 +279,73 @@ locexpr_describe_location (struct symbol *symbol, struct ui_file *stream)
   return 1;
 }
 
+
+/* Describe the location of SYMBOL as an agent value in VALUE, generating
+   any necessary bytecode in AX.
+
+   NOTE drow/2003-02-26: This function is extremely minimal, because
+   doing it correctly is extremely complicated and there is no
+   publicly available stub with tracepoint support for me to test
+   against.  When there is one this function should be revisited.  */
+
+void
+locexpr_tracepoint_var_ref (struct symbol * symbol, struct agent_expr * ax,
+			    struct axs_value * value)
+{
+  struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
+
+  if (dlbaton->size == 0)
+    error ("Symbol \"%s\" has been optimized out.",
+	   SYMBOL_PRINT_NAME (symbol));
+
+  if (dlbaton->size == 1
+      && dlbaton->data[0] >= DW_OP_reg0
+      && dlbaton->data[0] <= DW_OP_reg31)
+    {
+      value->kind = axs_lvalue_register;
+      value->u.reg = dlbaton->data[0] - DW_OP_reg0;
+    }
+  else if (dlbaton->data[0] == DW_OP_regx)
+    {
+      ULONGEST reg;
+      read_uleb128 (dlbaton->data + 1, dlbaton->data + dlbaton->size,
+		    &reg);
+      value->kind = axs_lvalue_register;
+      value->u.reg = reg;
+    }
+  else if (dlbaton->data[0] == DW_OP_fbreg)
+    {
+      /* And this is worse than just minimal; we should honor the frame base
+	 as above.  */
+      int frame_reg;
+      LONGEST frame_offset;
+      unsigned char *buf_end;
+
+      buf_end = read_sleb128 (dlbaton->data + 1, dlbaton->data + dlbaton->size,
+			      &frame_offset);
+      if (buf_end != dlbaton->data + dlbaton->size)
+	error ("Unexpected opcode after DW_OP_fbreg for symbol \"%s\".",
+	       SYMBOL_PRINT_NAME (symbol));
+
+      TARGET_VIRTUAL_FRAME_POINTER (ax->scope, &frame_reg, &frame_offset);
+      ax_reg (ax, frame_reg);
+      ax_const_l (ax, frame_offset);
+      ax_simple (ax, aop_add);
+
+      ax_const_l (ax, frame_offset);
+      ax_simple (ax, aop_add);
+      value->kind = axs_lvalue_memory;
+    }
+  else
+    error ("Unsupported DWARF opcode in the location of \"%s\".",
+	   SYMBOL_PRINT_NAME (symbol));
+}
+
 /* The set of location functions used with the DWARF-2 expression
    evaluator.  */
 struct location_funcs dwarf2_locexpr_funcs = {
   locexpr_read_variable,
   locexpr_read_needs_frame,
   locexpr_describe_location,
-  NULL
+  locexpr_tracepoint_var_ref
 };