SiFive: Add -z force-zicfilp option

sifive · Nov 21, 2023 · ce77d76 · ce77d76
1 parent fbe2b10
commit ce77d76
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Showing 7 changed files with 121 additions and 3 deletions.
diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c
@@ -184,6 +184,13 @@ struct _bfd_riscv_elf_obj_tdata
 
   /* All GNU_PROPERTY_RISCV_FEATURE_2_OR properties. */
   uint32_t gnu_or_prop;
+
+  /* True to warn when linking objects with incompatible
+     GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP.  */
+  bool zicfilp_warn;
+
+  /* PLT type based on security.  */
+  riscv_plt_type plt_type;
 };
 
 #define _bfd_riscv_elf_tdata(abfd) \
@@ -265,9 +272,22 @@ void
 riscv_elfNN_set_options (struct bfd_link_info *link_info,
 			 struct riscv_elf_params *params)
 {
+  struct bfd *output_bfd = link_info->output_bfd;
   riscv_elf_hash_table (link_info)->params = params;
+  switch (params->plt_type)
+    {
+    case PLT_ZICFILP:
+      _bfd_riscv_elf_tdata (output_bfd)->zicfilp_warn = true;
+      _bfd_riscv_elf_tdata (output_bfd)->gnu_and_prop
+        |= GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP;
+      break;
+
+    default:
+      break;
+    }
 }
 
+
 static bool
 riscv_info_to_howto_rela (bfd *abfd,
 			  arelent *cache_ptr,
@@ -5544,6 +5564,21 @@ elfNN_riscv_link_setup_gnu_properties (struct bfd_link_info *info)
   return pbfd;
 }
 
+/* Warn Zicfilp when -z force-zicfilp is enabled but the bfd doesn't have
+   the property in NOTE. */
+static void
+riscv_warn_zicfilp_if_necessary(const elf_property* prop, const bfd *abfd)
+{
+  if ((prop && !(prop->u.number & GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP))
+       || !prop)
+    {
+      _bfd_error_handler (_("%pB: warning: Zicfilp turned on by -z force-zicfilp when "
+                            "all inputs do not have ZICFILP in NOTE section."),
+                          abfd);
+    }
+}
+
+
 /* Implement elf_backend_merge_gnu_properties for RISC-V.  It serves as a
    wrapper function for _bfd_riscv_elf_merge_gnu_properties to account
    for the effect of GNU properties of the output_bfd.  */
@@ -5555,6 +5590,20 @@ elfNN_riscv_merge_gnu_properties (struct bfd_link_info *info,
 {
   uint32_t and_prop
     = _bfd_riscv_elf_tdata (info->output_bfd)->gnu_and_prop;
+
+  /* If output has been marked with CFILP using command line argument, give out
+     warning if necessary.  */
+  /* Properties are merged per type, hence only check for warnings when merging
+     GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP.  */
+  if (((aprop && aprop->pr_type == GNU_PROPERTY_RISCV_FEATURE_1_AND)
+	|| (bprop && bprop->pr_type == GNU_PROPERTY_RISCV_FEATURE_1_AND))
+      && (and_prop & GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP)
+      && (_bfd_riscv_elf_tdata (info->output_bfd)->zicfilp_warn))
+    {
+      riscv_warn_zicfilp_if_necessary(aprop, abfd);
+      riscv_warn_zicfilp_if_necessary(bprop, bbfd);
+    }
+
   uint32_t or_prop
     = _bfd_riscv_elf_tdata (info->output_bfd)->gnu_or_prop;
   return  _bfd_riscv_elf_merge_gnu_properties (info, abfd, aprop,

diff --git a/bfd/elfxx-riscv.c b/bfd/elfxx-riscv.c
@@ -2777,11 +2777,19 @@ _bfd_riscv_elf_link_setup_gnu_properties (struct bfd_link_info *info,
   if (ebfd != NULL && (and_prop || or_prop))
     {
       prop = _bfd_elf_get_property (ebfd,
-                                   GNU_PROPERTY_RISCV_FEATURE_1_AND,
-                                   4);
+                                    GNU_PROPERTY_RISCV_FEATURE_1_AND,
+                                    4);
+
+      if (and_prop & GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP
+          && !(prop->u.number & GNU_PROPERTY_RISCV_FEATURE_1_ZICFILP))
+      {
+            _bfd_error_handler (_("%pB: warning: Zicfilp turned on by -z force-zicfilp "
+                                  "when all inputs do not have ZICFILP in NOTE "
+                                  "section."), ebfd);
+      }
+
       prop->u.number |= and_prop;
       prop->pr_kind = property_number;
-
       prop = _bfd_elf_get_property (ebfd,
                                    GNU_PROPERTY_RISCV_FEATURE_2_OR,
                                    4);

diff --git a/bfd/elfxx-riscv.h b/bfd/elfxx-riscv.h
@@ -27,10 +27,25 @@
 
 #define RISCV_UNKNOWN_VERSION -1
 
+typedef enum
+{
+    PLT_NORMAL    = 0x0,  /* Normal plts.  */
+    PLT_ZICFILP   = 0x1   /* Landing pad plts.  */
+} riscv_plt_type;
+
+/* To indicate if LP is enabled with/without warning.  */
+typedef enum
+{
+  ZICFILP_NONE  = 0,  /* LP is not enabled.  */
+  ZICFILP_WARN  = 1,  /* LP is enabled with -z force-zicfilp.  */
+} riscv_enable_zicfilp_type;
+
 struct riscv_elf_params
 {
   /* Whether to relax code sequences to GP-relative addressing.  */
   bool relax_gp;
+  riscv_plt_type plt_type;
+  riscv_enable_zicfilp_type zicfilp_type;
 };
 
 extern void riscv_elf32_set_options (struct bfd_link_info *,

diff --git a/ld/emultempl/riscvelf.em b/ld/emultempl/riscvelf.em
@@ -46,8 +46,19 @@ PARSE_AND_LIST_LONGOPTS=${PARSE_AND_LIST_LONGOPTS}'
 PARSE_AND_LIST_OPTIONS=${PARSE_AND_LIST_OPTIONS}'
   fprintf (file, _("  --relax-gp                  Perform GP relaxation\n"));
   fprintf (file, _("  --no-relax-gp               Don'\''t perform GP relaxation\n"));
+  fprintf (file, _("  -z force-zicfilp            Turn on Zicfilp  mechanism and generate PLTs with landing pad. Generate warnings for missing Zicfilp on inputs\n\n"));
 '
 
+PARSE_AND_LIST_ARGS_CASE_Z_RISCV='
+      else if (strcmp (optarg, "force-zicfilp") == 0)
+	{
+          params.plt_type |= PLT_ZICFILP;
+          params.zicfilp_type = ZICFILP_WARN;
+	}
+'
+PARSE_AND_LIST_ARGS_CASE_Z="$PARSE_AND_LIST_ARGS_CASE_Z $PARSE_AND_LIST_ARGS_CASE_Z_RISCV"
+
+
 PARSE_AND_LIST_ARGS_CASES=${PARSE_AND_LIST_ARGS_CASES}'
     case OPTION_RELAX_GP:
       params.relax_gp = 1;

diff --git a/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp b/ld/testsuite/ld-riscv-elf/ld-riscv-elf.exp
@@ -232,6 +232,8 @@ if [istarget "riscv*-*-*"] {
     run_dump_test "property-zicfilp"
     run_dump_test "property-zicfiss"
     run_dump_test "property-combine-and-1"
+    run_dump_test "property-force-zicfilp"
+    run_dump_test "property-force-zicfilp-all-missing"
 
     # IFUNC testcases.
     # Check IFUNC by single type relocs.

diff --git a/ld/testsuite/ld-riscv-elf/property-force-zicfilp-all-missing.d b/ld/testsuite/ld-riscv-elf/property-force-zicfilp-all-missing.d
@@ -0,0 +1,16 @@
+#name: Warn with all missing GNU NOTE Zicfilp input
+#source: property1.s
+#source: property2.s
+#as: -mabi=lp64
+#ld: -shared -z force-zicfilp
+#warning: .*: warning: Zicfilp turned on by -z force-zicfilp.*$
+#readelf: -n
+
+# Should warn about the missing input ZICFILP NOTE but should
+# still mark output as ZICFILP
+
+Displaying notes found in: .note.gnu.property
+[ 	]+Owner[ 	]+Data size[ 	]+Description
+[ 	]+GNU[ 	]+0x00000020[ 	]+NT_GNU_PROPERTY_TYPE_0
+[ 	]+Properties: RISC-V AND feature: ZICFILP
+[ 	]+RISC-V OR feature: 
diff --git a/ld/testsuite/ld-riscv-elf/property-force-zicfilp.d b/ld/testsuite/ld-riscv-elf/property-force-zicfilp.d
@@ -0,0 +1,17 @@
+#name: Warn with one missing GNU NOTE Zicfilp input
+#source: property1.s
+#source: property2.s
+#as: -mabi=lp64 -defsym __property_zicfilp__=1 -defsym __property_zicfiss__=1
+#ld: -shared -z force-zicfilp
+#warning: .*: warning: Zicfilp turned on by -z force-zicfilp.*$
+#readelf: -n
+
+# Should warn about the missing input ZICFILP NOTE but should
+# still mark output as ZICFILP
+
+Displaying notes found in: .note.gnu.property
+[ 	]+Owner[ 	]+Data size[ 	]+Description
+[ 	]+GNU[ 	]+0x00000020[ 	]+NT_GNU_PROPERTY_TYPE_0
+[ 	]+Properties: RISC-V AND feature: ZICFILP
+[ 	]+RISC-V OR feature: ZICFISS
+