re PR target/84700 (ICE on 32-bit BE powerpc targets w/ -misel -O1)

	PR target/84700
	* combine.c (combine_simplify_rtx): Don't try to simplify if
	if_then_else_cond returned non-NULL, but either true_rtx or false_rtx
	are equal to x.

	* gcc.target/powerpc/pr84700.c: New test.

From-SVN: r258263

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5630a84a949a5215d579256967bff3ae9d3e6669..716e77abc99f2eb03d010ab70e30b4d882405b47 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2018-03-05  Jakub Jelinek  <jakub@redhat.com>
+
+       PR target/84700
+       * combine.c (combine_simplify_rtx): Don't try to simplify if
+       if_then_else_cond returned non-NULL, but either true_rtx or false_rtx
+       are equal to x.
+
 2018-03-05  Segher Boessenkool  <segher@kernel.crashing.org>
 
        * config/rs6000/rs6000.c (rs6000_loop_align): Don't align tiny loops

diff --git a/gcc/combine.c b/gcc/combine.c
index ddea5b18fe07cf282e9a3714c87de0309d9a9faf..a4efd11703cf903a042fd2de9c1609c35e8250b1 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -5734,7 +5734,11 @@ combine_simplify_rtx (rtx x, machine_mode op0_mode, int in_dest,
          /* If everything is a comparison, what we have is highly unlikely
             to be simpler, so don't use it.  */
          && ! (COMPARISON_P (x)
-               && (COMPARISON_P (true_rtx) || COMPARISON_P (false_rtx))))
+               && (COMPARISON_P (true_rtx) || COMPARISON_P (false_rtx)))
+         /* Similarly, if we end up with one of the expressions the same
+            as the original, it is certainly not simpler.  */
+         && ! rtx_equal_p (x, true_rtx)
+         && ! rtx_equal_p (x, false_rtx))
        {
          rtx cop1 = const0_rtx;
          enum rtx_code cond_code = simplify_comparison (NE, &cond, &cop1);

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9f9afb0df1290c0ab5d85c180135008465a266f8..ca2986b62210b829934e33600a4917590a6085ae 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-03-05  Jakub Jelinek  <jakub@redhat.com>
+
+       PR target/84700
+       * gcc.target/powerpc/pr84700.c: New test.
+
 2018-03-05  Nathan Sidwell  <nathan@acm.org>
 
        PR c++/84702

diff --git a/gcc/testsuite/gcc.target/powerpc/pr84700.c b/gcc/testsuite/gcc.target/powerpc/pr84700.c
new file mode 100644 (file)
index 0000000..c89094a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr84700.c
@@ -0,0 +1,12 @@
+/* PR target/84700 */
+/* { dg-do compile } */
+/* { dg-options "-O1 -misel" } */
+
+long long int
+foo (long long int x)
+{
+  long long int a = x < 2;
+  int b = a >= 0;
+
+  return a + ((x == 0) ? a : b);
+}