[NFC] Testcase for Issue #1413

A reproducible testcase for issue #1413 is added. The testcase checks if AVX512 pgmath functions are generated only when
avx512 target options are specified.

Author: shivaramaarao

test/f90_correct/inc/pgmath_avx512.mk

@@ -0,0 +1,24 @@
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+
+$(TEST): run
+
+EXTFLAGS=-O3 -march=x86-64 -mtune=core-avx2 -mfma  -mavx -mavx2 -mllvm -force-vector-width=16
+
+build:  $(SRC)/$(TEST).f90
+	-$(RM) $(TEST).$(EXESUFFIX) core *.d *.mod FOR*.DAT FTN* ftn* fort.*
+	@echo ------------------------------------ building test $@
+	-$(CC) -c $(CFLAGS) $(SRC)/check.c -o check.$(OBJX)
+	-$(FC) -c $(FFLAGS) $(EXTFLAGS) $(LDFLAGS) $(SRC)/$(TEST).f90 -o $(TEST).$(OBJX)
+	-$(FC) $(FFLAGS) $(LDFLAGS) $(TEST).$(OBJX) check.$(OBJX) $(LIBS) -o $(TEST).$(EXESUFFIX)
+
+
+run:
+	@echo ------------------------------------ executing test $(TEST)
+	$(TEST).$(EXESUFFIX)
+
+verify: ;
+

test/f90_correct/lit/pgmath_avx512.sh

@@ -0,0 +1,10 @@
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+# Shared lit script for each tests. Run bash commands that run tests with make.
+
+# REQUIRES: x86_64-host
+# RUN: env KEEP_FILES=%keep FLAGS=%flags TEST_SRC=%/s MAKE_FILE_DIR=%/S/.. bash %/S/runmake | tee %/t
+# RUN: cat %t | FileCheck %S/runmake

test/f90_correct/src/pgmath_avx512.f90

@@ -0,0 +1,37 @@
+!
+! Part of the LLVM Project, under the Apache License v2.0 with LLVM
+! Exceptions.
+! See https://llvm.org/LICENSE.txt for license information.
+! SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+!
+! Test for USE statement when there is rename of user-defined operator in the
+! ONLY option.
+! REQUIRES: x86_64-registered-target
+
+program main
+  real (kind=8) :: a(128), b(128), c(128)
+  integer :: res,expect
+  res=1
+  expect=2
+  do i=1,100
+   c(i) = log(a(i)) + log(b(i))
+  enddo
+  call sub1(a,b,c,128,res)
+  call check(res,expect,1);
+
+contains
+
+  subroutine sub1(a,b,c,N,res)
+   real(kind=8), intent(in) :: a(:), b(:)
+   real(kind=8), intent (out) :: c(:)
+   integer, intent(IN) :: N
+   integer, intent(OUT) :: res
+
+   do i=1,N,16
+     c(i) = exp(log(a(i))) + dlog(b(i))
+   enddo
+   res=2
+  end subroutine
+
+end program
+