compat-libgfortran-48/gcc48-pr78378.patch

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2021-01-21 00:56:15 +00:00
2017-05-30 Jakub Jelinek <jakub@redhat.com>
Backported from mainline
2016-11-16 Jakub Jelinek <jakub@redhat.com>
PR rtl-optimization/78378
* combine.c (make_extraction): Use force_to_mode for non-{REG,MEM}
inner only if pos is 0.
* gcc.c-torture/execute/pr78378.c: New test.
--- gcc/combine.c
+++ gcc/combine.c
@@ -7342,6 +7342,7 @@ make_extraction (machine_mode mode, rtx inner, HOST_WIDE_INT pos,
if (tmode != BLKmode
&& ((pos_rtx == 0 && (pos % BITS_PER_WORD) == 0
&& !MEM_P (inner)
+ && (pos == 0 || REG_P (inner))
&& (inner_mode == tmode
|| !REG_P (inner)
|| TRULY_NOOP_TRUNCATION_MODES_P (tmode, inner_mode)
--- /dev/null
+++ gcc/testsuite/gcc.c-torture/execute/pr78378.c
@@ -0,0 +1,18 @@
+/* PR rtl-optimization/78378 */
+
+unsigned long long __attribute__ ((noinline, noclone))
+foo (unsigned long long x)
+{
+ x <<= 41;
+ x /= 232;
+ return 1 + (unsigned short) x;
+}
+
+int
+main ()
+{
+ unsigned long long x = foo (1);
+ if (x != 0x2c24)
+ __builtin_abort();
+ return 0;
+}