Check whether symbols with MOVW_.ABS relocations require PLT entries (aarch64).

2019-02-19  Egeyar Bagcioglu  <[email protected]>

gold/
     PR gold/23870
     * aarch64.cc (Target_aarch64::Scan::global): Check if a symbol with
     R_AARCH64_MOVW_.ABS_* relocations requires a PLT entry.
     * testsuite/Makefile.am: Add aarch64_pr23870 test case.
     * testsuite/Makefile.in: Regenerate.
     * testsuite/aarch64_pr23870_bar.c: New file.
     * testsuite/aarch64_pr23870_foo.c: New file.
     * testsuite/aarch64_pr23870_main.S: New file.

Author: Egeyar Bagcioglu

gold/ChangeLog

@@ -1,3 +1,14 @@
+2019-02-19  Egeyar Bagcioglu  <[email protected]>
+
+     PR gold/23870
+     * aarch64.cc (Target_aarch64::Scan::global): Check if a symbol with
+     R_AARCH64_MOVW_.ABS_* relocations requires a PLT entry.
+     * testsuite/Makefile.am: Add aarch64_pr23870 test case.
+     * testsuite/Makefile.in: Regenerate.
+     * testsuite/aarch64_pr23870_bar.c: New file.
+     * testsuite/aarch64_pr23870_foo.c: New file.
+     * testsuite/aarch64_pr23870_main.S: New file.
+
 2019-02-12  Nick Clifton  <[email protected]>
 
 	* po/fr.po: Updated French translation.

gold/aarch64.cc

@@ -6496,6 +6496,17 @@ Target_aarch64<size, big_endian>::Scan::global(
 	  gold_error(_("%s: unsupported reloc %u in pos independent link."),
 		     object->name().c_str(), r_type);
 	}
+      // Make a PLT entry if necessary.
+      if (gsym->needs_plt_entry())
+	{
+	  target->make_plt_entry(symtab, layout, gsym);
+	  // Since this is not a PC-relative relocation, we may be
+	  // taking the address of a function. In that case we need to
+	  // set the entry in the dynamic symbol table to the address of
+	  // the PLT entry.
+	  if (gsym->is_from_dynobj() && !parameters->options().shared())
+	    gsym->set_needs_dynsym_value();
+	}
       break;
 
     case elfcpp::R_AARCH64_LD_PREL_LO19:        // 273

gold/testsuite/Makefile.am

@@ -3285,6 +3285,26 @@ pr22266: pr22266_main.o pr22266_ar.o gcctestdir/ld
 pr22266_ar.o: pr22266_a.o gcctestdir/ld
 	gcctestdir/ld -r -T $(srcdir)/pr22266_script.t -o $@ pr22266_a.o
 
+if DEFAULT_TARGET_AARCH64
+
+check_PROGRAMS += aarch64_pr23870
+aarch64_pr23870_SOURCES = aarch64_pr23870_foo.c
+aarch64_pr23870_DEPENDENCIES = \
+	gcctestdir/ld gcctestdir/as aarch64_pr23870_main.o \
+	aarch64_pr23870_foo.o aarch64_pr23870_bar.so
+aarch64_pr23870_LDFLAGS = -Wl,-R,. -L. -Wl,-l:aarch64_pr23870_bar.so
+aarch64_pr23870_LDADD = aarch64_pr23870_main.o
+aarch64_pr23870_main.o: aarch64_pr23870_main.S
+	$(COMPILE) -c -o $@ $<
+aarch64_pr23870_foo.o: aarch64_pr23870_foo.c
+	$(COMPILE) -c -o $@ $<
+aarch64_pr23870_bar.o: aarch64_pr23870_bar.c
+	$(COMPILE) -c -fPIC -o $@ $<
+aarch64_pr23870_bar.so: aarch64_pr23870_bar.o
+	$(COMPILE) -shared -o $@ $<
+
+endif DEFAULT_TARGET_AARCH64
+
 endif GCC
 endif NATIVE_LINKER
 

gold/testsuite/Makefile.in

@@ -0,0 +1,6 @@
+void bar (void);
+
+void bar ()
+{
+  return;
+}

gold/testsuite/aarch64_pr23870_bar.c

@@ -0,0 +1,6 @@
+void foo (void (*bar)(void));
+
+void foo (void (*bar)(void))
+{
+  bar();
+}

gold/testsuite/aarch64_pr23870_foo.c

@@ -0,0 +1,15 @@
+
+	.text
+	.globl main
+	.type main,#function
+main:
+	stp	x29, x30, [sp,#-16]!
+	mov	x29, sp
+	movz	x0, #:abs_g3:bar
+	movk	x0, #:abs_g2_nc:bar
+	movk	x0, #:abs_g1_nc:bar
+	movk	x0, #:abs_g0_nc:bar
+	add     x0, x0, #0x0
+	bl      foo
+	ldp     x29, x30, [sp],#16
+	ret