Hello!
As explained in the PR, ix86_cost switches to ix86_size_cost when -Os
is used. This defeats the intention of speed variable to
ix86_rtx_costs, which is set according to the optimization level at
the point of insn insertion.
2019-05-23 Uroš Bizjak <ubiz...@gmail.com>
PR target/90552
* config/i386/i386.c (gen_rtx_cost):
Use ix86_tune_cost instead of ix86_cost.
testsuite/ChangeLog:
2019-05-23 Uroš Bizjak <ubiz...@gmail.com>
PR target/90552
* gcc.target/i386/pr90552.c: New test.
Bootstrapped and regression tested on x86_64-linux-gnu {,-m32}.
Committed to mainline SVN.
Uros.
Index: config/i386/i386.c
===================================================================
--- config/i386/i386.c (revision 271562)
+++ config/i386/i386.c (working copy)
@@ -19124,7 +19124,8 @@ ix86_rtx_costs (rtx x, machine_mode mode, int oute
rtx mask;
enum rtx_code code = GET_CODE (x);
enum rtx_code outer_code = (enum rtx_code) outer_code_i;
- const struct processor_costs *cost = speed ? ix86_cost : &ix86_size_cost;
+ const struct processor_costs *cost
+ = speed ? ix86_tune_cost : &ix86_size_cost;
int src_cost;
switch (code)
Index: testsuite/gcc.target/i386/pr90552.c
===================================================================
--- testsuite/gcc.target/i386/pr90552.c (nonexistent)
+++ testsuite/gcc.target/i386/pr90552.c (working copy)
@@ -0,0 +1,11 @@
+/* PR target/90552 *
+/* { dg-do compile } */
+/* { dg-options "-Os" } */
+
+__attribute__((optimize(2)))
+int foo (int x)
+{
+ return x / 3;
+}
+
+/* { dg-final { scan-assembler-not "idiv" } } */
