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[1/2] RISC-V: Group relaxation features

Message ID 08e0064b49da8f235f75a45cc04a55e242edca97.1697259797.git.research_trasio@irq.a4lg.com
State New
Headers
Series RISC-V: Preparation for more generic linker relaxation |

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Commit Message

Tsukasa OI Oct. 14, 2023, 5:03 a.m. UTC 
  From: Tsukasa OI <research_trasio@irq.a4lg.com>

It does not only deduplicate multiple relaxation feature detection,
but enable more complex features so that querying the feature availability
will get too slow if we perform it per-relocation (not per-section).

Even if that wouldn't happen any time soon, it will improve the
maintainability around the linker relaxation code.

bfd/ChangeLog:

	* elfnn-riscv.c (RISCV_RELAX_RVC, RISCV_RELAX_GP): New.
	(relax_func_t): Add new relax_features argument.
	(_bfd_riscv_relax_call): Likewise.  Move feature detection to
	_bfd_riscv_relax_section.  Use bool for simplicity.
	(_bfd_riscv_relax_lui): Likewise.  Move feature detection to
	_bfd_riscv_relax_section.
	(_bfd_riscv_relax_tls_le): Likewise but features are not used.
	(_bfd_riscv_relax_align): Likewise but features are not used.
	(_bfd_riscv_relax_pc): Likewise.  Move feature detection to
	_bfd_riscv_relax_section.
	(_bfd_riscv_relax_section): Detect relaxation-related features
	and pass the flags to each relaxation function.
---
 bfd/elfnn-riscv.c | 40 +++++++++++++++++++++++++++++-----------
 1 file changed, 29 insertions(+), 11 deletions(-)
diff mbox series

Patch

diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c
index 09aa7be225ef..15652a08296d 100644
--- a/bfd/elfnn-riscv.c
+++ b/bfd/elfnn-riscv.c
@@ -4085,6 +4085,10 @@  _bfd_riscv_elf_merge_private_bfd_data (bfd *ibfd, struct bfd_link_info *info)
   return false;
 }
 
+/* Enabled relaxation features to use.  */
+#define RISCV_RELAX_RVC   0x01U
+#define RISCV_RELAX_GP    0x02U
+
 /* A second format for recording PC-relative hi relocations.  This stores the
    information required to relax them to GP-relative addresses.  */
 
@@ -4471,7 +4475,8 @@  typedef bool (*relax_func_t) (bfd *, asection *, asection *,
 			      Elf_Internal_Rela *,
 			      bfd_vma, bfd_vma, bfd_vma, bool *,
 			      riscv_pcgp_relocs *,
-			      bool undefined_weak);
+			      bool undefined_weak,
+			      unsigned relax_features);
 
 /* Relax AUIPC + JALR into JAL.  */
 
@@ -4484,13 +4489,15 @@  _bfd_riscv_relax_call (bfd *abfd, asection *sec, asection *sym_sec,
 		       bfd_vma reserve_size ATTRIBUTE_UNUSED,
 		       bool *again,
 		       riscv_pcgp_relocs *pcgp_relocs,
-		       bool undefined_weak ATTRIBUTE_UNUSED)
+		       bool undefined_weak ATTRIBUTE_UNUSED,
+		       unsigned relax_features)
 {
   bfd_byte *contents = elf_section_data (sec)->this_hdr.contents;
   bfd_vma foff = symval - (sec_addr (sec) + rel->r_offset);
   bool near_zero = (symval + RISCV_IMM_REACH / 2) < RISCV_IMM_REACH;
+  bool rvc = (relax_features & RISCV_RELAX_RVC) != 0;
   bfd_vma auipc, jalr;
-  int rd, r_type, len = 4, rvc = elf_elfheader (abfd)->e_flags & EF_RISCV_RVC;
+  int rd, r_type, len = 4;
 
   /* If the call crosses section boundaries, an alignment directive could
      cause the PC-relative offset to later increase, so we need to add in the
@@ -4590,15 +4597,16 @@  _bfd_riscv_relax_lui (bfd *abfd,
 		      bfd_vma reserve_size,
 		      bool *again,
 		      riscv_pcgp_relocs *pcgp_relocs,
-		      bool undefined_weak)
+		      bool undefined_weak,
+		      unsigned relax_features)
 {
   struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (link_info);
   bfd_byte *contents = elf_section_data (sec)->this_hdr.contents;
   /* Can relax to x0 even when gp relaxation is disabled.  */
-  bfd_vma gp = htab->params->relax_gp
+  bfd_vma gp = (relax_features & RISCV_RELAX_GP) != 0
 	       ? riscv_global_pointer_value (link_info)
 	       : 0;
-  int use_rvc = elf_elfheader (abfd)->e_flags & EF_RISCV_RVC;
+  bool use_rvc = (relax_features & RISCV_RELAX_RVC) != 0;
 
   BFD_ASSERT (rel->r_offset + 4 <= sec->size);
 
@@ -4703,7 +4711,8 @@  _bfd_riscv_relax_tls_le (bfd *abfd,
 			 bfd_vma reserve_size ATTRIBUTE_UNUSED,
 			 bool *again,
 			 riscv_pcgp_relocs *pcgp_relocs,
-			 bool undefined_weak ATTRIBUTE_UNUSED)
+			 bool undefined_weak ATTRIBUTE_UNUSED,
+			 unsigned relax_features ATTRIBUTE_UNUSED)
 {
   /* See if this symbol is in range of tp.  */
   if (RISCV_CONST_HIGH_PART (tpoff (link_info, symval)) != 0)
@@ -4745,7 +4754,8 @@  _bfd_riscv_relax_align (bfd *abfd, asection *sec,
 			bfd_vma reserve_size ATTRIBUTE_UNUSED,
 			bool *again ATTRIBUTE_UNUSED,
 			riscv_pcgp_relocs *pcgp_relocs ATTRIBUTE_UNUSED,
-			bool undefined_weak ATTRIBUTE_UNUSED)
+			bool undefined_weak ATTRIBUTE_UNUSED,
+			unsigned relax_features ATTRIBUTE_UNUSED)
 {
   bfd_byte *contents = elf_section_data (sec)->this_hdr.contents;
   bfd_vma alignment = 1, pos;
@@ -4805,11 +4815,12 @@  _bfd_riscv_relax_pc (bfd *abfd ATTRIBUTE_UNUSED,
 		     bfd_vma reserve_size,
 		     bool *again,
 		     riscv_pcgp_relocs *pcgp_relocs,
-		     bool undefined_weak)
+		     bool undefined_weak,
+		     unsigned relax_features)
 {
   struct riscv_elf_link_hash_table *htab = riscv_elf_hash_table (link_info);
   /* Can relax to x0 even when gp relaxation is disabled.  */
-  bfd_vma gp = htab->params->relax_gp
+  bfd_vma gp = (relax_features & RISCV_RELAX_GP) != 0
 	       ? riscv_global_pointer_value (link_info)
 	       : 0;
 
@@ -4965,6 +4976,13 @@  _bfd_riscv_relax_section (bfd *abfd, asection *sec,
   bfd_vma max_alignment, reserve_size = 0;
   riscv_pcgp_relocs pcgp_relocs;
   static asection *first_section = NULL;
+  unsigned relax_features = 0;
+
+  /* Detect available/enabled relaxation features.  */
+  if (elf_elfheader (abfd)->e_flags & EF_RISCV_RVC)
+    relax_features |= RISCV_RELAX_RVC;
+  if (htab->params->relax_gp)
+    relax_features |= RISCV_RELAX_GP;
 
   *again = false;
 
@@ -5208,7 +5226,7 @@  _bfd_riscv_relax_section (bfd *abfd, asection *sec,
 
       if (!relax_func (abfd, sec, sym_sec, info, rel, symval,
 		       max_alignment, reserve_size, again,
-		       &pcgp_relocs, undefined_weak))
+		       &pcgp_relocs, undefined_weak, relax_features))
 	goto fail;
     }