[PATCH v2 2/8] RISC-V: Treat R_RISCV_CALL and R_RISCV_CALL_PLT as the same.

[Fangrui Song]

On 2020-08-06, Nelson Chu wrote:
>	bfd/
>	* elfnn-riscv.c (riscv_elf_check_relocs): Treat R_RISCV_CALL and
>	R_RISCV_CALL_PLT as the same in the riscv_elf_check_relocs.
>	(riscv_elf_relocate_section): Remove the R_RISCV_CALL for the
>	unresolved reloc checks.
>
>	ld/
>	testsuite/ld-riscv-elf/lib-nopic-01a.s: Use R_RISCV_JAL rather
>	than R_RISCV_CALL.
>	testsuite/ld-riscv-elf/lib-nopic-01b.d: Likewise.
>	testsuite/ld-riscv-elf/lib-nopic-01b.s: Likewise.
>---
> bfd/elfnn-riscv.c                         | 19 ++++++++++---------
> ld/testsuite/ld-riscv-elf/lib-nopic-01a.s |  2 +-
> ld/testsuite/ld-riscv-elf/lib-nopic-01b.d |  2 +-
> ld/testsuite/ld-riscv-elf/lib-nopic-01b.s |  2 +-
> 4 files changed, 13 insertions(+), 12 deletions(-)
>
>diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c
>index fee169c..94ee184 100644
>--- a/bfd/elfnn-riscv.c
>+++ b/bfd/elfnn-riscv.c
>@@ -705,18 +705,21 @@ riscv_elf_check_relocs (bfd *abfd, struct bfd_link_info *info,
> 	    return FALSE;
> 	  break;
>
>+	case R_RISCV_CALL:
> 	case R_RISCV_CALL_PLT:
>-	  /* This symbol requires a procedure linkage table entry.  We
>+	  /* These symbols require a procedure linkage table entry.  We
> 	     actually build the entry in adjust_dynamic_symbol,
>-	     because this might be a case of linking PIC code without
>+	     because these might be a case of linking PIC code without
> 	     linking in any dynamic objects, in which case we don't
> 	     need to generate a procedure linkage table after all.  */
>
>-	  if (h != NULL)
>-	    {
>-	      h->needs_plt = 1;
>-	      h->plt.refcount += 1;
>-	    }
>+	  /* If it is a local symbol, then we resolve it directly
>+	     without creating a PLT entry.  */
>+	  if (h == NULL)
>+	    continue;
>+
>+	  h->needs_plt = 1;
>+	  h->plt.refcount += 1;
> 	  break;
>
> 	case R_RISCV_JAL:
>@@ -728,7 +731,6 @@ riscv_elf_check_relocs (bfd *abfd, struct bfd_link_info *info,
> 	    break;
> 	  goto static_reloc;
>
>-	case R_RISCV_CALL:
> 	case R_RISCV_PCREL_HI20:
> 	  /* In shared libraries, these relocs are known to bind locally,
> 	     except IFUNC symbol.  */
>@@ -2669,7 +2671,6 @@ riscv_elf_relocate_section (bfd *output_bfd,
> 	{
> 	  switch (r_type)
> 	    {
>-	    case R_RISCV_CALL:
> 	    case R_RISCV_JAL:
> 	    case R_RISCV_RVC_JUMP:
> 	      if (asprintf (&msg_buf,
>diff --git a/ld/testsuite/ld-riscv-elf/lib-nopic-01a.s b/ld/testsuite/ld-riscv-elf/lib-nopic-01a.s
>index c95cda0..632875d 100644
>--- a/ld/testsuite/ld-riscv-elf/lib-nopic-01a.s
>+++ b/ld/testsuite/ld-riscv-elf/lib-nopic-01a.s
>@@ -4,6 +4,6 @@
> 	.globl  func1
> 	.type   func1, @function
> func1:
>-	call    func2
>+	jal	func2
> 	jr      ra
> 	.size   func1, .-func1
>diff --git a/ld/testsuite/ld-riscv-elf/lib-nopic-01b.d b/ld/testsuite/ld-riscv-elf/lib-nopic-01b.d
>index 0d758a4..1c2c907 100644
>--- a/ld/testsuite/ld-riscv-elf/lib-nopic-01b.d
>+++ b/ld/testsuite/ld-riscv-elf/lib-nopic-01b.d
>@@ -2,4 +2,4 @@
> #source: lib-nopic-01b.s
> #as:
> #ld: -shared tmpdir/lib-nopic-01a.so
>-#error: .*relocation R_RISCV_CALL against `func1' can not be used when making a shared object; recompile with -fPIC
>+#error: .*relocation R_RISCV_JAL against `func1' can not be used when making a shared object; recompile with -fPIC
>diff --git a/ld/testsuite/ld-riscv-elf/lib-nopic-01b.s b/ld/testsuite/ld-riscv-elf/lib-nopic-01b.s
>index 97fe137..ea7b029 100644
>--- a/ld/testsuite/ld-riscv-elf/lib-nopic-01b.s
>+++ b/ld/testsuite/ld-riscv-elf/lib-nopic-01b.s
>@@ -4,6 +4,6 @@
> 	.globl  func2
> 	.type   func2, @function
> func2:
>-	call    func1
>+	jal	func1
> 	jr      ra
> 	.size   func2, .-func2
>-- 
>2.7.4
>

Happy to see this:)

I think this is not tightly connected to the rest of the ifunc patch
series?