[glibc] riscv: Change the relocations handled for RTLD_BOOTSTRAP

[glibc] riscv: Change the relocations handled for RTLD_BOOTSTRAP

[Fangrui Song]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=57919813e732dff2c6cfd1c95056cbc265058bc2

commit 57919813e732dff2c6cfd1c95056cbc265058bc2
Author: Fangrui Song <maskray@google.com>
Date:   Wed Jun 15 18:42:03 2022 -0700

    riscv: Change the relocations handled for RTLD_BOOTSTRAP
    
    The RTLD_BOOTSTRAP branch is used to relocate ld.so itself.  It only
    needs to handle RELATIVE, GLOB_DAT, and the symbolic relocation type
    (R_RISCV_{32,64}).  NONE and IRELATIVE can be removed.
    
    The code relies on ld.so having DT_RELACOUNT so that the RTLD_BOOTSTRAP
    branch does not need handle RELATIVE.  Drop this minor size
    optimization for clarity.
    
    Acked-by: Palmer Dabbelt <palmer@rivosinc.com>

Diff:
---
 sysdeps/riscv/dl-machine.h | 23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/sysdeps/riscv/dl-machine.h b/sysdeps/riscv/dl-machine.h
index 9e026ae011..a60a452952 100644
--- a/sysdeps/riscv/dl-machine.h
+++ b/sysdeps/riscv/dl-machine.h
@@ -181,7 +181,15 @@ elf_machine_rela (struct link_map *map, struct r_scope_elem *scope[],
 
   switch (r_type)
     {
-#ifndef RTLD_BOOTSTRAP
+    case R_RISCV_RELATIVE:
+      *addr_field = map->l_addr + reloc->r_addend;
+      break;
+    case R_RISCV_JUMP_SLOT:
+    case __WORDSIZE == 64 ? R_RISCV_64 : R_RISCV_32:
+      *addr_field = value;
+      break;
+
+# ifndef RTLD_BOOTSTRAP
     case __WORDSIZE == 64 ? R_RISCV_TLS_DTPMOD64 : R_RISCV_TLS_DTPMOD32:
       if (sym_map)
 	*addr_field = sym_map->l_tls_modid;
@@ -232,13 +240,6 @@ elf_machine_rela (struct link_map *map, struct r_scope_elem *scope[],
 	memcpy (reloc_addr, (void *)value, size);
 	break;
       }
-#endif
-
-#if !defined RTLD_BOOTSTRAP
-    case R_RISCV_RELATIVE:
-      *addr_field = map->l_addr + reloc->r_addend;
-      break;
-#endif
 
     case R_RISCV_IRELATIVE:
       value = map->l_addr + reloc->r_addend;
@@ -247,13 +248,9 @@ elf_machine_rela (struct link_map *map, struct r_scope_elem *scope[],
       *addr_field = value;
       break;
 
-    case R_RISCV_JUMP_SLOT:
-    case __WORDSIZE == 64 ? R_RISCV_64 : R_RISCV_32:
-      *addr_field = value;
-      break;
-
     case R_RISCV_NONE:
       break;
+# endif /* !RTLD_BOOTSTRAP */
 
     default:
       _dl_reloc_bad_type (map, r_type, 0);