[PATCH] i386: Load external function address via GOT slot

[H.J. Lu]

With noplt attribute, we load the external function address via the GOT
slot so that linker won't create an PLT entry for extern function address.

gcc/

        PR target/88954
        * config/i386/i386.c (ix86_force_load_from_GOT_p): Also check
        noplt attribute.

gcc/testsuite/

        PR target/88954
        * gcc.target/i386/pr88954-1.c: New test.
        * gcc.target/i386/pr88954-2.c: Likewise.
---
 gcc/config/i386/i386.c                    |  6 +++++-
 gcc/testsuite/gcc.target/i386/pr88954-1.c | 15 +++++++++++++++
 gcc/testsuite/gcc.target/i386/pr88954-2.c | 16 ++++++++++++++++
 3 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/gcc.target/i386/pr88954-1.c
 create mode 100644 gcc/testsuite/gcc.target/i386/pr88954-2.c

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 8abff99cc62..9ca5596c4af 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -15189,10 +15189,14 @@ ix86_force_load_from_GOT_p (rtx x)
 {
   return ((TARGET_64BIT || HAVE_AS_IX86_GOT32X)
          && !TARGET_PECOFF && !TARGET_MACHO
-         && !flag_plt && !flag_pic
+         && !flag_pic
          && ix86_cmodel != CM_LARGE
          && GET_CODE (x) == SYMBOL_REF
          && SYMBOL_REF_FUNCTION_P (x)
+         && (!flag_plt
+             || (SYMBOL_REF_DECL (x)
+                 && lookup_attribute ("noplt",
+                                      DECL_ATTRIBUTES (SYMBOL_REF_DECL (x)))))
          && !SYMBOL_REF_LOCAL_P (x));
 }
 
diff --git a/gcc/testsuite/gcc.target/i386/pr88954-1.c 
b/gcc/testsuite/gcc.target/i386/pr88954-1.c
new file mode 100644
index 00000000000..69cb940ae4f
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr88954-1.c
@@ -0,0 +1,15 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -fno-pic -fplt" } */
+
+extern void bar (void) __attribute__((noplt));
+
+void *
+foo (void)
+{
+  return &bar;
+}
+
+/* { dg-final { scan-assembler "mov\(l|q\)\[ \t\]*bar@GOTPCREL" { target { ! 
ia32 } } } } */
+/* { dg-final { scan-assembler "movl\[ \t\]*bar@GOT," { target { ia32 && 
got32x_reloc } } } } */
+/* { dg-final { scan-assembler-not "\(mov|lea\)\(l|q\)\[ \t\]*\(\\\$|\)bar," { 
target { ! ia32 } } } } */
+/* { dg-final { scan-assembler-not "\(mov|lea\)l\[ \t\]*\(\\\$|\)bar," { 
target { ia32 && got32x_reloc } } } } */
diff --git a/gcc/testsuite/gcc.target/i386/pr88954-2.c 
b/gcc/testsuite/gcc.target/i386/pr88954-2.c
new file mode 100644
index 00000000000..3bc4ee47bae
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr88954-2.c
@@ -0,0 +1,16 @@
+/* { dg-do compile { target *-*-linux* } } */
+/* { dg-options "-O2 -fno-pic -fplt" } */
+
+extern void bar (void) __attribute__((noplt));
+extern void *p;
+
+void
+foo (void)
+{
+  p = &bar;
+}
+
+/* { dg-final { scan-assembler "mov\(l|q\)\[ \t\]*bar@GOTPCREL" { target { ! 
ia32 } } } } */
+/* { dg-final { scan-assembler "movl\[ \t\]*bar@GOT," { target { ia32 && 
got32x_reloc } } } } */
+/* { dg-final { scan-assembler-not "mov\(l|q\)\[ \t\]*\\\$bar," { target { ! 
ia32 } } } } */
+/* { dg-final { scan-assembler-not "mov\(l|q\)\[ \t\]*\\\$bar," { target { 
ia32 && got32x_reloc } } } } */
-- 
2.20.1