diff mbox series

[v4,1/9] RISC-V: Fix local GOT and reloc size calculation for TLS.

Message ID 20240220175556.304692-2-ishitatsuyuki@gmail.com
State Unresolved
Headers
Series RISC-V: Implement TLS Descriptors. |

Checks

Context Check Description
snail/binutils-gdb-check warning Git am fail log

Commit Message

Tatsuyuki Ishi Feb. 20, 2024, 5:55 p.m. UTC 
  The previous code did not account correctly for two cases:
* A TLS symbol can be referenced with multiple TLS types (although rare),
  in which case it only allocated the maximum slot size among the types,
  instead of the sum.
* TLS relocations are only needed for DLLs, unlike normal symbols which
  requires relocations for all PIE code.

Modify the logic to account for the two cases.

bfd/
    * elfnn-riscv.c (riscv_elf_size_dynamic_sections): Handle relocation
    sizing for TLS and non-TLS symbols differently, with the former
    requiring relocs on DLL while the latter requiring on PIE.
    Allocate GOT slots and relocation slots for each TLS type separately,
    accounting for the possibility of a TLS variable getting referenced by
    multiple symbols.
ld/
    * testsuite/ld-riscv-elf/ld-riscv-elf.exp: Updated.
    * testsuite/ld-riscv-elf/tls*: New testcase for TLS GD and IE, with
    symbols referred by both types and global and local symbols.
---
 bfd/elfnn-riscv.c                          | 27 ++++++++++++++++-----
 ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp |  8 +++++++
 ld/testsuite/ld-riscv-elf/tls.d            | 15 ++++++++++++
 ld/testsuite/ld-riscv-elf/tls.s            | 28 ++++++++++++++++++++++
 ld/testsuite/ld-riscv-elf/tlsbin.d         |  7 ++++++
 ld/testsuite/ld-riscv-elf/tlslib.s         |  6 +++++
 6 files changed, 85 insertions(+), 6 deletions(-)
 create mode 100644 ld/testsuite/ld-riscv-elf/tls.d
 create mode 100644 ld/testsuite/ld-riscv-elf/tls.s
 create mode 100644 ld/testsuite/ld-riscv-elf/tlsbin.d
 create mode 100644 ld/testsuite/ld-riscv-elf/tlslib.s
diff mbox series

Patch

diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c
index 951b19a911d..e5cecd79cf3 100644
--- a/bfd/elfnn-riscv.c
+++ b/bfd/elfnn-riscv.c
@@ -1559,12 +1559,27 @@  riscv_elf_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
 	  if (*local_got > 0)
 	    {
 	      *local_got = s->size;
-	      s->size += RISCV_ELF_WORD_BYTES;
-	      if (*local_tls_type & GOT_TLS_GD)
-		s->size += RISCV_ELF_WORD_BYTES;
-	      if (bfd_link_pic (info)
-		  || (*local_tls_type & (GOT_TLS_GD | GOT_TLS_IE)))
-		srel->size += sizeof (ElfNN_External_Rela);
+	      if (*local_tls_type & (GOT_TLS_GD | GOT_TLS_IE))
+		{
+		  if (*local_tls_type & GOT_TLS_GD)
+		    {
+		      s->size += 2 * RISCV_ELF_WORD_BYTES;
+		      if (bfd_link_dll (info))
+			srel->size += sizeof (ElfNN_External_Rela);
+		    }
+		  if (*local_tls_type & GOT_TLS_IE)
+		    {
+		      s->size += RISCV_ELF_WORD_BYTES;
+		      if (bfd_link_dll (info))
+			srel->size += sizeof (ElfNN_External_Rela);
+		    }
+		}
+	      else
+		{
+		  s->size += RISCV_ELF_WORD_BYTES;
+		  if (bfd_link_pic (info))
+		    srel->size += sizeof (ElfNN_External_Rela);
+		}
 	    }
 	  else
 	    *local_got = (bfd_vma) -1;
diff --git a/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp b/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
index 7e1281d826b..a1dd0e5e37e 100644
--- a/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
+++ b/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
@@ -319,4 +319,12 @@  if [istarget "riscv*-*-*"] {
     run_dump_test "pcrel-reloc-rel-pie"
     run_dump_test "pcrel-reloc-abs-nopie"
     run_dump_test "pcrel-reloc-abs-pie"
+
+    run_ld_link_tests {
+       { "Build shared library for TLS runtime"
+	 "-shared" "" "" {tlslib.s}
+	 {} "tlslib.so" }
+    }
+    run_dump_test "tls"
+    run_dump_test "tlsbin"
 }
diff --git a/ld/testsuite/ld-riscv-elf/tls.d b/ld/testsuite/ld-riscv-elf/tls.d
new file mode 100644
index 00000000000..e7f20309bf1
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/tls.d
@@ -0,0 +1,15 @@ 
+#source: tls.s
+#ld: --shared tmpdir/tlslib.so
+#readelf: -Wr
+
+Relocation section '.rela.dyn' at offset 0x[0-9a-f]+ contains 5 entries:
+ +Offset +Info +Type +Symbol's Value +Symbol's Name \+ Addend
+[0-9a-f]+ +[0-9a-f]+ R_RISCV_TLS_DTPMOD64 +0
+[0-9a-f]+ +[0-9a-f]+ R_RISCV_TLS_TPREL64 +4
+[0-9a-f]+ +[0-9a-f]+ R_RISCV_TLS_DTPMOD64 +0+ sg1 \+ 0
+[0-9a-f]+ +[0-9a-f]+ R_RISCV_TLS_DTPREL64 +0+ sg1 \+ 0
+[0-9a-f]+ +[0-9a-f]+ R_RISCV_TLS_TPREL64 +0+ sg1 \+ 0
+
+Relocation section '.rela.plt' at offset 0x[0-9a-f]+ contains 1 entry:
+ +Offset +Info +Type +Symbol's Value +Symbol's Name \+ Addend
+[0-9a-f]+ +[0-9a-f]+ R_RISCV_JUMP_SLOT +0+ __tls_get_addr \+ 0
diff --git a/ld/testsuite/ld-riscv-elf/tls.s b/ld/testsuite/ld-riscv-elf/tls.s
new file mode 100644
index 00000000000..79e9bc20374
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/tls.s
@@ -0,0 +1,28 @@ 
+	.section	.tbss,"awT",@nobits
+	.global sg1
+sg1:
+	.zero	4
+sl1:
+	.zero	4
+
+	.text
+	.globl	_start
+	.type	_start,@function
+_start:
+	/* GD, global var */
+	la.tls.gd	a0,sg1
+	call  __tls_get_addr
+
+	/* IE, global var */
+	la.tls.ie	a0,sg1
+	add	a0,a0,tp
+
+	/* GD, local var */
+	la.tls.gd	a0,sl1
+	call  __tls_get_addr
+
+	/* IE, local var */
+	la.tls.ie	a0,sl1
+	add	a0,a0,tp
+
+	ret
diff --git a/ld/testsuite/ld-riscv-elf/tlsbin.d b/ld/testsuite/ld-riscv-elf/tlsbin.d
new file mode 100644
index 00000000000..cdcd51a9199
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/tlsbin.d
@@ -0,0 +1,7 @@ 
+#source: tls.s
+#ld: -no-pie tmpdir/tlslib.so
+#readelf: -Wr
+
+Relocation section '.rela.plt' at offset 0x[0-9a-f]+ contains 1 entry:
+ +Offset +Info +Type +Symbol's Value +Symbol's Name \+ Addend
+[0-9a-f]+ +[0-9a-f]+ R_RISCV_JUMP_SLOT +[0-9a-f]+ __tls_get_addr \+ 0
diff --git a/ld/testsuite/ld-riscv-elf/tlslib.s b/ld/testsuite/ld-riscv-elf/tlslib.s
new file mode 100644
index 00000000000..17c770786d0
--- /dev/null
+++ b/ld/testsuite/ld-riscv-elf/tlslib.s
@@ -0,0 +1,6 @@ 
+	.text
+	/* Dummy.  */
+	.globl	__tls_get_addr
+	.type	__tls_get_addr,@function
+__tls_get_addr:
+	ret