arm: Handle fixed PIC register in require_pic_register (PR target/115485)

Commit r9-4307-g89d7557202d25a forgot to accept a fixed PIC register
when extending the assert in require_pic_register.

arm_pic_register can be set explicitly by the user
(e.g. -mpic-register=r9) or implicitly as the default value with
-fpic/-fPIC/-fPIE and -mno-pic-data-is-text-relative -mlong-calls, and
we want to use/accept it when recording cfun->machine->pic_reg as used
to be the case.

	PR target/115485
	gcc/
	* config/arm/arm.cc (require_pic_register): Fix typos in
	comment. Handle fixed arm_pic_register.

	gcc/testsuite/
	* g++.target/arm/pr115485.C: New test.

2 files changed, 19 insertions, 2 deletions

diff --git a/gcc/config/arm/arm.cc b/gcc/config/arm/arm.cc
index 00499a2..670f487 100644
--- a/gcc/config/arm/arm.cc
+++ b/gcc/config/arm/arm.cc
@@ -8086,8 +8086,8 @@ legitimate_pic_operand_p (rtx x)
 
 /* Record that the current function needs a PIC register.  If PIC_REG is null,
    a new pseudo is allocated as PIC register, otherwise PIC_REG is used.  In
-   both case cfun->machine->pic_reg is initialized if we have not already done
-   so.  COMPUTE_NOW decide whether and where to set the PIC register.  If true,
+   both cases cfun->machine->pic_reg is initialized if we have not already done
+   so.  COMPUTE_NOW decides whether and where to set the PIC register.  If true,
    PIC register is reloaded in the current position of the instruction stream
    irregardless of whether it was loaded before.  Otherwise, it is only loaded
    if not already done so (crtl->uses_pic_offset_table is null).  Note that
@@ -8107,6 +8107,7 @@ require_pic_register (rtx pic_reg, bool compute_now)
   if (!crtl->uses_pic_offset_table || compute_now)
     {
       gcc_assert (can_create_pseudo_p ()
+		  || (arm_pic_register != INVALID_REGNUM)
 		  || (pic_reg != NULL_RTX
 		      && REG_P (pic_reg)
 		      && GET_MODE (pic_reg) == Pmode));
diff --git a/gcc/testsuite/g++.target/arm/pr115485.C b/gcc/testsuite/g++.target/arm/pr115485.C
new file mode 100644
index 0000000..491b48c
--- /dev/null
+++ b/gcc/testsuite/g++.target/arm/pr115485.C
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "-fPIE -mno-pic-data-is-text-relative -mlong-calls -ffunction-sections" } */
+
+struct c1 {
+  virtual void func1() = 0;
+};
+struct  c2 {
+  virtual ~c2() {}
+};
+struct c3 : c2, c1 {
+  void func1() override;
+  void func3();
+};
+void c3::func1() {
+  func3();
+}