powerpc: Fix ICE with fp conditional move (PR target/93073)

The following testcase ICEs, because for TFmode the particular subtraction
pattern (*subtf3) is not enabled with the given options.  Using
expand_simple_binop instead of emitting the subtraction by hand just moves
the ICE one insn later, NEG of ABS is not then recognized, etc., but
ultimately the problem is that when rs6000_emit_cmove is called for floating
point operand mode (and earlier condition ensures that in that case
compare_mode is also floating point), the expander makes sure the
operand mode is SFDF, but for the comparison mode nothing checks it, yet
there is just one *fsel* pattern with 2 separate SFDF iterators.

The following patch fixes it by giving up if compare_mode is not SFmode or
DFmode.

2020-01-21  Jakub Jelinek  <jakub@redhat.com>

	PR target/93073
	* config/rs6000/rs6000.c (rs6000_emit_cmove): If using fsel, punt for
	compare_mode other than SFmode or DFmode.

	* gcc.target/powerpc/pr93073.c: New test.

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a48cb990a45dbd13ebe06411b57406977e4e2ae9..2b0541ea1f0f7c280fccd22db815fefa45b139f7 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2020-01-22  Jakub Jelinek  <jakub@redhat.com>
+
+       Backported from mainline
+       2020-01-21  Jakub Jelinek  <jakub@redhat.com>
+
+       PR target/93073
+       * config/rs6000/rs6000.c (rs6000_emit_cmove): If using fsel, punt for
+       compare_mode other than SFmode or DFmode.
+
 2020-01-22  Jakub Jelinek  <jakub@redhat.com>
 
        Backported from mainline

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index a670096145b9dc5f256edf5aad0111a819a93244..87d60078bb0d14ceaba6ccad54a3e564e875d6c7 100644 (file)
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -23255,6 +23255,11 @@ rs6000_emit_cmove (rtx dest, rtx op, rtx true_cond, rtx false_cond)
 
   /* At this point we know we can use fsel.  */
 
+  /* Don't allow compare_mode other than SFmode or DFmode, for others there
+     is no fsel instruction.  */
+  if (compare_mode != SFmode && compare_mode != DFmode)
+    return 0;
+
   /* Reduce the comparison to a comparison against zero.  */
   if (! is_against_zero)
     {

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d49da0ada2760849f6bf493e6d8c46a22a076609..24c597b33c7fc99183501b6a26729f419d3caf52 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2020-01-22  Jakub Jelinek  <jakub@redhat.com>
+
+       Backported from mainline
+       2020-01-21  Jakub Jelinek  <jakub@redhat.com>
+
+       PR target/93073
+       * gcc.target/powerpc/pr93073.c: New test.
+
 2020-01-22  Jakub Jelinek  <jakub@redhat.com>
 
        Backported from mainline

diff --git a/gcc/testsuite/gcc.target/powerpc/pr93073.c b/gcc/testsuite/gcc.target/powerpc/pr93073.c
new file mode 100644 (file)
index 0000000..6a0a473
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr93073.c
@@ -0,0 +1,16 @@
+/* PR target/93073 */
+/* { dg-do compile { target powerpc_vsx_ok } } */
+/* { dg-options "-mvsx -O1 -ffinite-math-only -fno-trapping-math" } */
+
+void bar (void);
+
+void
+foo (long double x, double y, double z)
+{
+  for (;;)
+    {
+      double a = x > 0.0 ? y : z;
+      if (a == 0.0)
+       bar ();
+    }
+}