http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53366
Bug #: 53366
Summary: wrong code generation by tree vectorizer using AVX
Classification: Unclassified
Product: gcc
Version: 4.7.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: mar...@mpa-garching.mpg.de
Created attachment 27410
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27410
Testcase demonstrating the problem
The attached code is the reduction of a numerical library. It should print
"2.816937e+08" if executed correctly.
Using the current head of the 4.7 branch and trunk, and compiling on an
Intel Core i3-2120 using
gcc testcase.c -std=c99 -g -O3 -march=native -fno-tree-vectorize
everything works as expected.
When omitting the "-fno-tree-vectorize", random results are printed, and a
different number is generated for every run.
The testcase is the result of several hours' reduction. Currently I don't have
time to reduce it further.
