[PATCH 2/2] xtensa: Implement new target hook: TARGET_CONSTANT_OK_FOR_CPROP_P

[Takayuki 'January June' Suwa via Gcc-patches]

This patch implements new target hook TARGET_CONSTANT_OK_FOR_CPROP_P in
order to exclude CONST_INTs that cannot fit into a MOVI machine instruction
from cprop.

gcc/ChangeLog:

        * config/xtensa/xtensa.c (TARGET_CONSTANT_OK_FOR_CPROP_P):
        New macro definition.
        (xtensa_constant_ok_for_cprop_p):
        Implement the hook as mentioned above.
---
 gcc/config/xtensa/xtensa.cc | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/gcc/config/xtensa/xtensa.cc b/gcc/config/xtensa/xtensa.cc
index ac52c015a94..5c432cc65aa 100644
--- a/gcc/config/xtensa/xtensa.cc
+++ b/gcc/config/xtensa/xtensa.cc
@@ -191,6 +191,7 @@ static bool xtensa_can_eliminate (const int from 
ATTRIBUTE_UNUSED,
 static HOST_WIDE_INT xtensa_starting_frame_offset (void);
 static unsigned HOST_WIDE_INT xtensa_asan_shadow_offset (void);
 static bool xtensa_function_ok_for_sibcall (tree, tree);
+static bool xtensa_constant_ok_for_cprop_p (const_rtx);
 static rtx xtensa_delegitimize_address (rtx);
 
 
@@ -345,12 +346,15 @@ static rtx xtensa_delegitimize_address (rtx);
 #undef TARGET_HAVE_SPECULATION_SAFE_VALUE
 #define TARGET_HAVE_SPECULATION_SAFE_VALUE speculation_safe_value_not_needed
 
-#undef TARGET_DELEGITIMIZE_ADDRESS
-#define TARGET_DELEGITIMIZE_ADDRESS xtensa_delegitimize_address
-
 #undef TARGET_FUNCTION_OK_FOR_SIBCALL
 #define TARGET_FUNCTION_OK_FOR_SIBCALL xtensa_function_ok_for_sibcall
 
+#undef TARGET_CONSTANT_OK_FOR_CPROP_P
+#define TARGET_CONSTANT_OK_FOR_CPROP_P xtensa_constant_ok_for_cprop_p
+
+#undef TARGET_DELEGITIMIZE_ADDRESS
+#define TARGET_DELEGITIMIZE_ADDRESS xtensa_delegitimize_address
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 
@@ -4983,6 +4987,16 @@ xtensa_function_ok_for_sibcall (tree decl 
ATTRIBUTE_UNUSED, tree exp ATTRIBUTE_U
   return true;
 }
 
+/* Implement TARGET_CONSTANT_OK_FOR_CPROP_P.  */
+static bool
+xtensa_constant_ok_for_cprop_p (const_rtx x)
+{
+  if (CONST_INT_P (x) && ! xtensa_simm12b (INTVAL (x)))
+    return false;
+
+  return true;
+}
+
 static rtx
 xtensa_delegitimize_address (rtx op)
 {
-- 
2.20.1