[ARM/FDPIC v6 21/24] [ARM] FDPIC: Handle stack-protector combined patterns

The recent stack_protect_combined_set_insn and
stack_protect_combined_test_insn force recomputing of GOT base, but
need to take into account that in FDPIC mode, the PIC register is
fixed by the ABI (r9).

2019-09-10  Christophe Lyon  <christophe.lyon@st.com>

	gcc/
	* config/arm/arm.md (stack_protect_combined_set_insn): Handle
	FDPIC mode.
	(stack_protect_combined_test_insn): Likewise.

From-SVN: r275582

gcc/ChangeLog

 2019-09-10  Christophe Lyon  <christophe.lyon@st.com>
+
+	* config/arm/arm.md (stack_protect_combined_set_insn): Handle
+	FDPIC mode.
+	(stack_protect_combined_test_insn): Likewise.
+
+2019-09-10  Christophe Lyon  <christophe.lyon@st.com>
 	Mickaël Guêné <mickael.guene@st.com>
 
 	* config/arm/arm.c (arm_load_tp): Add FDPIC support.

gcc/config/arm/arm.md

@@ -8270,8 +8270,15 @@
 {
   if (flag_pic)
     {
+      rtx pic_reg;
+
+      if (TARGET_FDPIC)
+	  pic_reg = gen_rtx_REG (Pmode, FDPIC_REGNUM);
+      else
+	  pic_reg = operands[3];
+
       /* Forces recomputing of GOT base now.  */
-      legitimize_pic_address (operands[1], SImode, operands[2], operands[3],
+      legitimize_pic_address (operands[1], SImode, operands[2], pic_reg,
 			      true /*compute_now*/);
     }
   else
@@ -8346,8 +8353,15 @@
 
   if (flag_pic)
     {
+      rtx pic_reg;
+
+      if (TARGET_FDPIC)
+	  pic_reg = gen_rtx_REG (Pmode, FDPIC_REGNUM);
+      else
+	  pic_reg = operands[4];
+
       /* Forces recomputing of GOT base now.  */
-      legitimize_pic_address (operands[1], SImode, operands[3], operands[4],
+      legitimize_pic_address (operands[1], SImode, operands[3], pic_reg,
 			      true /*compute_now*/);
     }
   else