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Re: [PATCH 1/2] simplify-rtx: The truncation of an IOR can have all bits set (PR81423)
On 24/07/17 09:50, Segher Boessenkool wrote:
On Wed, Jul 19, 2017 at 12:19:32AM -0600, Jeff Law wrote:
On 07/18/2017 01:36 PM, Segher Boessenkool wrote:
* simplify-rtx.c (simplify_truncation): Handle truncating an IOR
with a constant that is -1 in the truncated to mode.
OK. A testcase would be advisable :-)
jeff
Like this. Is this okay for trunk? (Is int32plus the correct test
to use here?)
We sometimes use the __mode__ attribute to force certain sizes in C types.
For example: typedef int ditype __attribute__ ((mode (DI)));
Maybe you can do this to force the right sizes. I don't know if there are any targets
that don't support DImode ops though :)
Kyrill
Segher
2017-07-24 Segher Boessenkool <segher@kernel.crashing.org>
gcc/testsuite/
PR rtl-optimization/81423
* gcc.c-torture/execute/pr81423.c: New testcase.
---
gcc/testsuite/gcc.c-torture/execute/pr81423.c | 30 +++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr81423.c
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr81423.c b/gcc/testsuite/gcc.c-torture/execute/pr81423.c
new file mode 100644
index 0000000..75c3518
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr81423.c
@@ -0,0 +1,30 @@
+/* { dg-require-effective-target int32plus } */
+
+extern void abort (void);
+
+unsigned long long int ll = 0;
+unsigned long long int ull1 = 1ULL;
+unsigned long long int ull2 = 12008284144813806346ULL;
+unsigned long long int ull3;
+
+void
+foo (void)
+{
+ ll = -5597998501375493990LL;
+
+ ll = (5677365550390624949L - ll) - (ull1 > 0);
+ ull3 = (unsigned int)
+ (2067854353L <<
+ (((ll + -2129105131L) ^ 10280750144413668236ULL) -
+ 10280750143997242009ULL)) >> ((2873442921854271231ULL | ull2)
+ - 12098357307243495419ULL);
+}
+
+int
+main (void)
+{
+ foo ();
+ if (ull3 != 3998784)
+ abort ();
+ return 0;
+}