[X86, Darwin] Backport fix for pr82920 (part 1).

[X86, Darwin] Backport fix for pr82920 (part 1).

The various thunks output codes have inconsistent output
mechanisms. The patch factors out some common code that
writes out the jumps and uses the regular output scheme
that accounts for __USER_LABEL_PREFIX__.

The testsuite changes are largely mechanical compensation
for the revised output (and the fact that Darwin doesn't
use non-PIC by default).

gcc/

2019-09-28  Iain Sandoe  <iain@sandoe.co.uk>

	Backport from mainline.
	2019-05-12  Iain Sandoe  <iain@sandoe.co.uk>

	PR target/82920
	* config/i386/i386.c (ix86_output_jmp_thunk_or_indirect): New.
	(ix86_output_indirect_branch_via_reg): Use output mechanism
	accounting for __USER_LABEL_PREFIX__.
	(ix86_output_indirect_branch_via_push): Likewise.
	(ix86_output_function_return): Likewise.
	(ix86_output_indirect_function_return): Likewise.

gcc/testsuite/

2019-09-28  Iain Sandoe  <iain@sandoe.co.uk>

	Backport from mainline.
	2019-05-12  Iain Sandoe  <iain@sandoe.co.uk>
	    Dominique d'Humieres  <dominiq@gcc.gnu.org>

	PR target/82920
	* gcc.target/i386/indirect-thunk-1.c: Adjust scan-asms for Darwin,
	do not use -fno-pic on Darwin.
	* gcc.target/i386/indirect-thunk-2.c: Likewise.
	* gcc.target/i386/indirect-thunk-3.c: Likewise.
	* gcc.target/i386/indirect-thunk-4.c: Likewise.
	* gcc.target/i386/indirect-thunk-7.c: Likewise.
	* gcc.target/i386/indirect-thunk-attr-1.c: Likewise.
	* gcc.target/i386/indirect-thunk-attr-2.c: Likewise.
	* gcc.target/i386/indirect-thunk-attr-3.c: Likewise.
	* gcc.target/i386/indirect-thunk-attr-4.c: Likewise.
	* gcc.target/i386/indirect-thunk-attr-5.c: Likewise.
	* gcc.target/i386/indirect-thunk-attr-6.c: Likewise.
	* gcc.target/i386/indirect-thunk-attr-7.c: Likewise.
	* gcc.target/i386/indirect-thunk-attr-8.c: Likewise.
	* gcc.target/i386/indirect-thunk-extern-1.c: Likewise.
	* gcc.target/i386/indirect-thunk-extern-2.c: Likewise.
	* gcc.target/i386/indirect-thunk-extern-3.c: Likewise.
	* gcc.target/i386/indirect-thunk-extern-4.c: Likewise.
	* gcc.target/i386/indirect-thunk-extern-7.c: Likewise.
	* gcc.target/i386/indirect-thunk-inline-1.c: Likewise.
	* gcc.target/i386/indirect-thunk-inline-2.c: Likewise.
	* gcc.target/i386/indirect-thunk-inline-3.c: Likewise.
	* gcc.target/i386/indirect-thunk-inline-4.c: Likewise.
	* gcc.target/i386/indirect-thunk-inline-7.c: Likewise.
	* gcc.target/i386/indirect-thunk-register-1.c: Likewise.
	* gcc.target/i386/indirect-thunk-register-2.c: Likewise.
	* gcc.target/i386/indirect-thunk-register-3.c: Likewise.
	* gcc.target/i386/indirect-thunk-register-4.c: Likewise.
	* gcc.target/i386/ret-thunk-1.c: Likewise.
	* gcc.target/i386/ret-thunk-10.c: Likewise.
	* gcc.target/i386/ret-thunk-11.c: Likewise.
	* gcc.target/i386/ret-thunk-12.c: Likewise.
	* gcc.target/i386/ret-thunk-13.c: Likewise.
	* gcc.target/i386/ret-thunk-14.c: Likewise.
	* gcc.target/i386/ret-thunk-15.c: Likewise.
	* gcc.target/i386/ret-thunk-16.c: Likewise.
	* gcc.target/i386/ret-thunk-2.c: Likewise.
	* gcc.target/i386/ret-thunk-22.c: Likewise.
	* gcc.target/i386/ret-thunk-23.c: Likewise.
	* gcc.target/i386/ret-thunk-24.c: Likewise.
	* gcc.target/i386/ret-thunk-3.c: Likewise.
	* gcc.target/i386/ret-thunk-4.c: Likewise.
	* gcc.target/i386/ret-thunk-5.c: Likewise.
	* gcc.target/i386/ret-thunk-6.c: Likewise.
	* gcc.target/i386/ret-thunk-7.c: Likewise.
	* gcc.target/i386/ret-thunk-8.c: Likewise.
	* gcc.target/i386/ret-thunk-9.c: Likewise.

From-SVN: r276257