Translate DW_CFA_expression/DW_CFA_val_expression properly to imply pushing CFA before given expression.

5 files changed, 32 insertions, 8 deletions

diff --git a/libdw/ChangeLog b/libdw/ChangeLog
index 5fa75151..f927032e 100644
--- a/libdw/ChangeLog
+++ b/libdw/ChangeLog
@@ -1,3 +1,12 @@
+2010-04-26  Roland McGrath  <roland@redhat.com>
+
+	* dwarf_getlocation.c (__libdw_intern_expression): Take new arg CFAP.
+	Prepend DW_OP_call_frame_cfa if true.
+	(getlocation): Update caller.
+	* dwarf_frame_cfa.c (dwarf_frame_cfa): Likewise.
+	* dwarf_frame_register.c (dwarf_frame_register): Likewise.
+	* libdwP.h: Update decl.
+
 2010-04-22  Roland McGrath  <roland@redhat.com>
 
 	* cfi.c (execute_cfi): Track last-set CFA regno and offset even
diff --git a/libdw/dwarf_frame_cfa.c b/libdw/dwarf_frame_cfa.c
index d1c57108..03c5fbd2 100644
--- a/libdw/dwarf_frame_cfa.c
+++ b/libdw/dwarf_frame_cfa.c
@@ -84,7 +84,7 @@ dwarf_frame_cfa (fs, ops, nops)
       result = __libdw_intern_expression
 	(NULL, fs->cache->other_byte_order,
 	 fs->cache->e_ident[EI_CLASS] == ELFCLASS32 ? 4 : 8,
-	 &fs->cache->expr_tree, &fs->cfa_data.expr, false,
+	 &fs->cache->expr_tree, &fs->cfa_data.expr, false, false,
 	 ops, nops, IDX_debug_frame);
       break;
 
diff --git a/libdw/dwarf_frame_register.c b/libdw/dwarf_frame_register.c
index 3d232e95..e42b76bf 100644
--- a/libdw/dwarf_frame_register.c
+++ b/libdw/dwarf_frame_register.c
@@ -1,5 +1,5 @@
 /* Get register location expression for frame.
-   Copyright (C) 2009 Red Hat, Inc.
+   Copyright (C) 2009-2010 Red Hat, Inc.
    This file is part of Red Hat elfutils.
 
    Red Hat elfutils is free software; you can redistribute it and/or modify
@@ -131,7 +131,7 @@ dwarf_frame_register (fs, regno, ops_mem, ops, nops)
 				       fs->cache->other_byte_order,
 				       address_size,
 				       &fs->cache->expr_tree, &block,
-				       reg->rule == reg_val_expression,
+				       true, reg->rule == reg_val_expression,
 				       ops, nops, IDX_debug_frame) < 0)
 	  return -1;
 	break;
diff --git a/libdw/dwarf_getlocation.c b/libdw/dwarf_getlocation.c
index 720b20f4..f362fe22 100644
--- a/libdw/dwarf_getlocation.c
+++ b/libdw/dwarf_getlocation.c
@@ -1,5 +1,5 @@
 /* Return location expression list.
-   Copyright (C) 2000-2009 Red Hat, Inc.
+   Copyright (C) 2000-2010 Red Hat, Inc.
    This file is part of Red Hat elfutils.
    Written by Ulrich Drepper <drepper@redhat.com>, 2000.
 
@@ -221,7 +221,8 @@ int
 internal_function
 __libdw_intern_expression (Dwarf *dbg,
 			   bool other_byte_order, unsigned int address_size,
-			   void **cache, const Dwarf_Block *block, bool valuep,
+			   void **cache, const Dwarf_Block *block,
+			   bool cfap, bool valuep,
 			   Dwarf_Op **llbuf, size_t *listlen, int sec_index)
 {
   /* Check whether we already looked at this list.  */
@@ -444,6 +445,9 @@ __libdw_intern_expression (Dwarf *dbg,
       ++n;
     }
 
+  if (cfap)
+    ++n;
+
   /* Allocate the array.  */
   Dwarf_Op *result;
   if (dbg != NULL)
@@ -463,6 +467,16 @@ __libdw_intern_expression (Dwarf *dbg,
   *llbuf = result;
   *listlen = n;
 
+  if (cfap)
+    {
+      /* Synthesize the operation to push the CFA before the expression.  */
+      --n;
+      result[0].atom = DW_OP_call_frame_cfa;
+      result[0].number = 0;
+      result[0].number2 = 0;
+      result[0].offset = -1;
+    }
+
   do
     {
       /* We populate the array from the back since the list is backwards.  */
@@ -507,7 +521,8 @@ getlocation (struct Dwarf_CU *cu, const Dwarf_Block *block,
 	     Dwarf_Op **llbuf, size_t *listlen, int sec_index)
 {
   return __libdw_intern_expression (cu->dbg, cu->dbg->other_byte_order,
-				    cu->address_size, &cu->locs, block, false,
+				    cu->address_size, &cu->locs, block,
+				    false, false,
 				    llbuf, listlen, sec_index);
 }
 
diff --git a/libdw/libdwP.h b/libdw/libdwP.h
index 248a58d5..44beac67 100644
--- a/libdw/libdwP.h
+++ b/libdw/libdwP.h
@@ -433,10 +433,10 @@ extern int __libdw_intern_expression (Dwarf *dbg,
 				      bool other_byte_order,
 				      unsigned int address_size,
 				      void **cache, const Dwarf_Block *block,
-				      bool valuep,
+				      bool cfap, bool valuep,
 				      Dwarf_Op **llbuf, size_t *listlen,
 				      int sec_index)
-  __nonnull_attribute__ (4, 5, 7, 8) internal_function;
+  __nonnull_attribute__ (4, 5, 8, 9) internal_function;
 
 
 /* Return error code of last failing function call.  This value is kept