From: Alex Coplan <alex.coplan@arm.com>
Date: Tue, 11 May 2021 12:11:09 +0000 (+0100)
Subject: arm: Avoid emitting bogus CFA adjusts for CMSE nonsecure calls [PR99725]
X-Git-Tag: upstream/12.2.0~7982
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2ac1f0eb3887335b7a7e845812956fa436e72a91;p=platform%2Fupstream%2Fgcc.git

arm: Avoid emitting bogus CFA adjusts for CMSE nonsecure calls [PR99725]

The PR shows us attaching REG_CFA_ADJUST_CFA notes to stack pointer
adjustments emitted in cmse_nonsecure_call_inline_register_clear (when
-march=armv8.1-m.main). However, the stack pointer is not guaranteed to
be the CFA reg. If we're at -O0 or we have -fno-omit-frame-pointer, then
the frame pointer will be used as the CFA reg, and these notes on the sp
adjustments will lead to ICEs in dwarf2out_frame_debug_adjust_cfa.

This patch avoids emitting these notes if the current function has a
frame pointer.

gcc/ChangeLog:

	PR target/99725
	* config/arm/arm.c (cmse_nonsecure_call_inline_register_clear):
	Avoid emitting CFA adjusts on the sp if we have the fp.

gcc/testsuite/ChangeLog:

	PR target/99725
	* gcc.target/arm/cmse/pr99725.c: New test.
---

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 0371d98..2962071 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -18774,10 +18774,14 @@ cmse_nonsecure_call_inline_register_clear (void)
 		  imm = gen_int_mode (- lazy_store_stack_frame_size, SImode);
 		  add_insn = emit_insn (gen_addsi3 (stack_pointer_rtx,
 						    stack_pointer_rtx, imm));
-		  arm_add_cfa_adjust_cfa_note (add_insn,
-					       - lazy_store_stack_frame_size,
-					       stack_pointer_rtx,
-					       stack_pointer_rtx);
+		  /* If we have the frame pointer, then it will be the
+		     CFA reg.  Otherwise, the stack pointer is the CFA
+		     reg, so we need to emit a CFA adjust.  */
+		  if (!frame_pointer_needed)
+		    arm_add_cfa_adjust_cfa_note (add_insn,
+						 - lazy_store_stack_frame_size,
+						 stack_pointer_rtx,
+						 stack_pointer_rtx);
 		  emit_insn (gen_lazy_store_multiple_insn (stack_pointer_rtx));
 		}
 	      /* Save VFP callee-saved registers.  */
@@ -18815,10 +18819,11 @@ cmse_nonsecure_call_inline_register_clear (void)
 		  rtx_insn *add_insn =
 		    emit_insn (gen_addsi3 (stack_pointer_rtx,
 					   stack_pointer_rtx, imm));
-		  arm_add_cfa_adjust_cfa_note (add_insn,
-					       lazy_store_stack_frame_size,
-					       stack_pointer_rtx,
-					       stack_pointer_rtx);
+		  if (!frame_pointer_needed)
+		    arm_add_cfa_adjust_cfa_note (add_insn,
+						 lazy_store_stack_frame_size,
+						 stack_pointer_rtx,
+						 stack_pointer_rtx);
 		}
 	      /* Restore VFP callee-saved registers.  */
 	      else
diff --git a/gcc/testsuite/gcc.target/arm/cmse/pr99725.c b/gcc/testsuite/gcc.target/arm/cmse/pr99725.c
new file mode 100644
index 0000000..284da18
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/cmse/pr99725.c
@@ -0,0 +1,5 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-mcmse -g" } */
+typedef int __attribute__((cmse_nonsecure_call)) (*t)();
+t f;
+void g() { f(); }