Delay evaluation of alignment expressions in output sections

git commit 702d16713 broke expressions using CONSTANT(COMMONPAGESIZE)
in ALIGN or SUBALIGN of output section statements, because these
optional fields were evaluated at script parse time and the patch in
question delayed setting of config.commonpagesize.  The right thing to
do is keep the tree representation of those fields for later
evaluation.

	PR 23571
	* ldlang.h (section_alignment): Make it an expression tree.
	(subsection_alignment): Likewise.
	* ldlang.c (topower): Delete.
	(output_section_statement_newfunc): Adjust initialization.
	(init_os): Evaluate section_alignment.
	(lang_size_sections_1): Likewise.
	(size_input_section): Evaluate subsection_alignment.
	(lang_enter_output_section_statement): Don't evaluate here.
	(lang_new_phdr): Use exp_get_vma rather than exp_get_value_int.
	* ldexp.h (exp_get_value_int): Delete.
	(exp_get_power): Declare.
	* ldexp.c (exp_get_value_int): Delete.
	(exp_get_power): New function.
	* emultempl/pe.em (place_orphan): Build expression for section
	alignment.
	* emultempl/pep.em (place_orphan): Likewise.
	* testsuite/ld-scripts/pr23571.d,
	* testsuite/ld-scripts/pr23571.t: New test.
	* testsuite/ld-scripts/align.exp: Run it.

1 files changed, 16 insertions, 32 deletions

diff --git a/ld/ldlang.c b/ld/ldlang.c
index 350baf2..8878ccd 100644
--- a/ld/ldlang.c
+++ b/ld/ldlang.c
@@ -1199,8 +1199,8 @@ output_section_statement_newfunc (struct bfd_hash_entry *entry,
   ret = (struct out_section_hash_entry *) entry;
   memset (&ret->s, 0, sizeof (ret->s));
   ret->s.header.type = lang_output_section_statement_enum;
-  ret->s.output_section_statement.subsection_alignment = -1;
-  ret->s.output_section_statement.section_alignment = -1;
+  ret->s.output_section_statement.subsection_alignment = NULL;
+  ret->s.output_section_statement.section_alignment = NULL;
   ret->s.output_section_statement.block_value = 1;
   lang_list_init (&ret->s.output_section_statement.children);
   lang_statement_append (stat_ptr, &ret->s, &ret->s.header.next);
@@ -2193,8 +2193,9 @@ init_os (lang_output_section_statement_type *s, flagword flags)
     exp_init_os (s->load_base);
 
   /* If supplied an alignment, set it.  */
-  if (s->section_alignment != -1)
-    s->bfd_section->alignment_power = s->section_alignment;
+  if (s->section_alignment != NULL)
+    s->bfd_section->alignment_power = exp_get_power (s->section_alignment,
+						     "section alignment");
 }
 
 /* Make sure that all output sections mentioned in an expression are
@@ -4706,8 +4707,10 @@ size_input_section
 	 is greater than any seen before, then record it too.  Perform
 	 the alignment by inserting a magic 'padding' statement.  */
 
-      if (output_section_statement->subsection_alignment != -1)
-	i->alignment_power = output_section_statement->subsection_alignment;
+      if (output_section_statement->subsection_alignment != NULL)
+	i->alignment_power
+	  = exp_get_power (output_section_statement->subsection_alignment,
+			   "subsection alignment");
 
       if (o->alignment_power < i->alignment_power)
 	o->alignment_power = i->alignment_power;
@@ -5147,7 +5150,8 @@ lang_size_sections_1
 		    section_alignment = os->bfd_section->alignment_power;
 		  }
 		else
-		  section_alignment = os->section_alignment;
+		  section_alignment = exp_get_power (os->section_alignment,
+						     "section alignment");
 
 		/* Align to what the section needs.  */
 		if (section_alignment > 0)
@@ -5225,7 +5229,8 @@ lang_size_sections_1
 		       only align according to the value in the output
 		       statement.  */
 		    if (os->lma_region != os->region)
-		      section_alignment = os->section_alignment;
+		      section_alignment = exp_get_power (os->section_alignment,
+							 "section alignment");
 		    if (section_alignment > 0)
 		      lma = align_power (lma, section_alignment);
 		  }
@@ -6673,25 +6678,6 @@ lang_add_output (const char *name, int from_script)
     }
 }
 
-static int
-topower (int x)
-{
-  unsigned int i = 1;
-  int l;
-
-  if (x < 0)
-    return -1;
-
-  for (l = 0; l < 32; l++)
-    {
-      if (i >= (unsigned int) x)
-	return l;
-      i <<= 1;
-    }
-
-  return 0;
-}
-
 lang_output_section_statement_type *
 lang_enter_output_section_statement (const char *output_section_statement_name,
 				     etree_type *address_exp,
@@ -6727,10 +6713,8 @@ lang_enter_output_section_statement (const char *output_section_statement_name,
     einfo (_("%F%P:%pS: error: align with input and explicit align specified\n"),
 	   NULL);
 
-  os->subsection_alignment =
-    topower (exp_get_value_int (subalign, -1, "subsection alignment"));
-  os->section_alignment =
-    topower (exp_get_value_int (align, -1, "section alignment"));
+  os->subsection_alignment = subalign;
+  os->section_alignment = align;
 
   os->load_base = ebase;
   return os;
@@ -7748,7 +7732,7 @@ lang_new_phdr (const char *name,
   n = (struct lang_phdr *) stat_alloc (sizeof (struct lang_phdr));
   n->next = NULL;
   n->name = name;
-  n->type = exp_get_value_int (type, 0, "program header type");
+  n->type = exp_get_vma (type, 0, "program header type");
   n->filehdr = filehdr;
   n->phdrs = phdrs;
   n->at = at;