[28/77] Use is_a <scalar_int_mode> for miscellaneous types of test

This patch adds is_a <scalar_int_mode> checks to various places
that were explicitly or implicitly restricted to integers already,
in cases where adding an explicit is_a <scalar_int_mode> is useful
for later patches.

In simplify_if_then_else, the:

  GET_MODE (XEXP (XEXP (t, 0), N))

expressions were equivalent to:

  GET_MODE (XEXP (t, 0))

due to the type of operation.

2017-08-30  Richard Sandiford  <richard.sandiford@linaro.org>
	    Alan Hayward  <alan.hayward@arm.com>
	    David Sherwood  <david.sherwood@arm.com>

gcc/
	* combine.c (sign_extend_short_imm): Add is_a <scalar_int_mode>
	checks.
	(try_combine): Likewise.
	(simplify_if_then_else): Likewise.
	* cse.c (cse_insn): Likewise.
	* dwarf2out.c (mem_loc_descriptor): Likewise.
	* emit-rtl.c (gen_lowpart_common): Likewise.
	* simplify-rtx.c (simplify_truncation): Likewise.
	(simplify_binary_operation_1): Likewise.
	(simplify_const_relational_operation): Likewise.
	(simplify_ternary_operation): Likewise.
	* tree-ssa-loop-ivopts.c (force_expr_to_var_cost): Likewise.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>

From-SVN: r251480

1 files changed, 4 insertions, 3 deletions

diff --git a/gcc/cse.c b/gcc/cse.c
index 755ac3b..02f5fc3 100644
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -4878,13 +4878,14 @@ cse_insn (rtx_insn *insn)
 	 value.  */
 
       if (flag_expensive_optimizations && ! src_related
+	  && is_a <scalar_int_mode> (mode, &int_mode)
 	  && GET_CODE (src) == AND && CONST_INT_P (XEXP (src, 1))
-	  && GET_MODE_SIZE (mode) < UNITS_PER_WORD)
+	  && GET_MODE_SIZE (int_mode) < UNITS_PER_WORD)
 	{
 	  machine_mode tmode;
 	  rtx new_and = gen_rtx_AND (VOIDmode, NULL_RTX, XEXP (src, 1));
 
-	  FOR_EACH_WIDER_MODE (tmode, mode)
+	  FOR_EACH_WIDER_MODE (tmode, int_mode)
 	    {
 	      if (GET_MODE_SIZE (tmode) > UNITS_PER_WORD)
 		break;
@@ -4905,7 +4906,7 @@ cse_insn (rtx_insn *insn)
 		    if (REG_P (larger_elt->exp))
 		      {
 			src_related
-			  = gen_lowpart (mode, larger_elt->exp);
+			  = gen_lowpart (int_mode, larger_elt->exp);
 			break;
 		      }