LoongArch Port: gcc/testsuite

LoongArch Port: gcc/testsuite

2022-03-29  Chenghua Xu  <xuchenghua@loongson.cn>
	    Lulu Cheng  <chenglulu@loongson.cn>

gcc/testsuite/ChangeLog:

	* g++.dg/cpp0x/constexpr-rom.C: Add build options for LoongArch.
	* g++.old-deja/g++.abi/ptrmem.C: Add LoongArch support.
	* g++.old-deja/g++.pt/ptrmem6.C: xfail for LoongArch.
	* gcc.dg/20020312-2.c: Add LoongArch support.
	* c-c++-common/zero-scratch-regs-10.c: Like wise
	* c-c++-common/zero-scratch-regs-11.c: Like wise
	* c-c++-common/zero-scratch-regs-8.c: Like wise
	* c-c++-common/zero-scratch-regs-9.c: Like wise
	* gcc.dg/loop-8.c: Skip on LoongArch.
	* gcc.dg/torture/stackalign/builtin-apply-2.c: Likewise.
	* gcc.dg/tree-ssa/ssa-fre-3.c: Likewise.
	* go.test/go-test.exp: Define the LoongArch target.
	* lib/target-supports.exp: Like wise.
	* gcc.target/loongarch/loongarch.exp: New file.
	* gcc.target/loongarch/tst-asm-const.c: Like wise.
	* gcc.target/loongarch/larch-builtin.c: Like wise.