From 97976c0757ad3173ac00d1e32e335f3f960b0b9f Mon Sep 17 00:00:00 2001
From: Nelson Chu <nelson.chu@sifive.com>
Date: Tue, 10 Nov 2020 19:33:38 -0800
Subject: [PATCH] RISC-V: Enable ifunc if it was supported in the binutils for
 linux toolchain.

	gcc/
	* configure: Regenerated.
	* configure.ac: If ifunc was supported in the binutils for
	linux toolchain, then set enable_gnu_indirect_function to yes.
---
 gcc/configure    | 37 +++++++++++++++++++++++++++++++++++++
 gcc/configure.ac | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 72 insertions(+)

diff --git a/gcc/configure b/gcc/configure
index 9d2fd0dc30b..dbda4415a17 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -23407,6 +23407,43 @@ else
 fi
 
 
+case "${target}" in
+  riscv*-*-linux*)
+    { $as_echo "$as_me:${as_lineno-$LINENO}: checking linker ifunc IRELATIVE support" >&5
+$as_echo_n "checking linker ifunc IRELATIVE support... " >&6; }
+    cat > conftest.s <<EOF
+	.text
+	.type	foo_resolver, @function
+foo_resolver:
+	ret
+	.size	foo_resolver, .-foo_resolver
+
+	.globl	foo
+	.type	foo, %gnu_indirect_function
+	.set	foo, foo_resolver
+
+	.globl	bar
+	.type	bar, @function
+bar:
+	call	foo
+	ret
+	.size	bar, .-bar
+EOF
+    if test x$gcc_cv_as != x \
+       && test x$gcc_cv_ld != x \
+       && test x$gcc_cv_readelf != x \
+       && $gcc_cv_as -o conftest.o conftest.s > /dev/null 2>&1 \
+       && $gcc_cv_ld -o conftest conftest.o > /dev/null 2>&1 \
+       && $gcc_cv_readelf --relocs --wide conftest \
+	  | grep R_RISCV_IRELATIVE > /dev/null 2>&1; then
+      enable_gnu_indirect_function=yes
+    fi
+    rm -f conftest conftest.o conftest.s
+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $enable_gnu_indirect_function" >&5
+$as_echo "$enable_gnu_indirect_function" >&6; }
+    ;;
+esac
+
 gif=`if test x$enable_gnu_indirect_function = xyes; then echo 1; else echo 0; fi`
 
 cat >>confdefs.h <<_ACEOF
diff --git a/gcc/configure.ac b/gcc/configure.ac
index 73034bb902b..08f3034986e 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -2807,6 +2807,41 @@ Valid choices are 'yes' and 'no'.]) ;;
   esac],
  [enable_gnu_indirect_function="$default_gnu_indirect_function"])
 
+case "${target}" in
+  riscv*-*-linux*)
+    AC_MSG_CHECKING(linker ifunc IRELATIVE support)
+    cat > conftest.s <<EOF
+	.text
+	.type	foo_resolver, @function
+foo_resolver:
+	ret
+	.size	foo_resolver, .-foo_resolver
+
+	.globl	foo
+	.type	foo, %gnu_indirect_function
+	.set	foo, foo_resolver
+
+	.globl	bar
+	.type	bar, @function
+bar:
+	call	foo
+	ret
+	.size	bar, .-bar
+EOF
+    if test x$gcc_cv_as != x \
+       && test x$gcc_cv_ld != x \
+       && test x$gcc_cv_readelf != x \
+       && $gcc_cv_as -o conftest.o conftest.s > /dev/null 2>&1 \
+       && $gcc_cv_ld -o conftest conftest.o > /dev/null 2>&1 \
+       && $gcc_cv_readelf --relocs --wide conftest \
+	  | grep R_RISCV_IRELATIVE > /dev/null 2>&1; then
+      enable_gnu_indirect_function=yes
+    fi
+    rm -f conftest conftest.o conftest.s
+    AC_MSG_RESULT($enable_gnu_indirect_function)
+    ;;
+esac
+
 gif=`if test x$enable_gnu_indirect_function = xyes; then echo 1; else echo 0; fi`
 AC_DEFINE_UNQUOTED(HAVE_GNU_INDIRECT_FUNCTION, $gif,
 [Define if your system supports gnu indirect functions.])
-- 
2.30.2