diff mbox

[7/9] cprop: Leave RTX_FRAME_RELATED_P instructions alone

Message ID 9e78a6b1a3239ef2bfa57361f9d452647ac123f3.1465347472.git.segher@kernel.crashing.org
State New
Headers show

Commit Message

Segher Boessenkool June 8, 2016, 1:47 a.m. UTC 
Doing cprop on frame-related instructions blows up spectacularly.
So don't.


2016-06-07  Segher Boessenkool  <segher@kernel.crashing.org>

	* regcprop.c (copyprop_hardreg_forward_1): Don't change
	RTX_FRAME_RELATED_P instructions.

---
 gcc/regcprop.c | 3 +++
 1 file changed, 3 insertions(+)
diff mbox

Patch

diff --git a/gcc/regcprop.c b/gcc/regcprop.c
index 933cc8a..0c01aab 100644
--- a/gcc/regcprop.c
+++ b/gcc/regcprop.c
@@ -829,6 +829,10 @@  copyprop_hardreg_forward_1 (basic_block bb, struct value_data *vd)
 	    }
 	}
 
+      /* Don't change prologue instructions.  */
+      if (RTX_FRAME_RELATED_P (insn))
+	set = NULL;
+
       /* Special-case plain move instructions, since we may well
 	 be able to do the move from a different register class.  */
       if (set && REG_P (SET_SRC (set)))