On Wed, Jun 15, 2016 at 11:01:05AM +0200, Richard Biener wrote:
> And I don't understand the layout_type change either - it looks to me
> it could just have used
> 
>   SET_TYPE_MODE (type, GET_MODE_COMPLEX_MODE (TYPE_MODE 
> (TREE_TYPE (type))));
> 
> and be done with it.  To me that looks a lot safer.

I made this change in the trunk, and now I would like approval for applying
this code which includes the above change in the GCC 6.2 branch.

Here is the change for the trunk:
https://gcc.gnu.org/ml/gcc-patches/2016-06/msg01489.html

I tested it on both a big endian power7 and a little endian power8 systems with
no regressions.  Is it ok to apply to the GCC 6.2 branch?

[gcc]
2016-06-22  Michael Meissner  <meissner@linux.vnet.ibm.com>

	Back port from trunk
	2016-06-21  Michael Meissner  <meissner@linux.vnet.ibm.com>

	* stor-layout.c (layout_type): Move setting complex MODE to
	layout_type, instead of setting it ahead of time by the caller.

	Back port from trunk
	2016-05-11  Alan Modra  <amodra@gmail.com>

	* config/rs6000/rs6000.c (is_complex_IBM_long_double,
	abi_v4_pass_in_fpr): New functions.
	(rs6000_function_arg_boundary): Exclude complex IBM long double
	from 64-bit alignment when ABI_V4.
	(rs6000_function_arg, rs6000_function_arg_advance_1,
	rs6000_gimplify_va_arg): Use abi_v4_pass_in_fpr.

	Back port from trunk
	2016-05-02  Michael Meissner  <meissner@linux.vnet.ibm.com>

	* machmode.h (mode_complex): Add support to give the complex mode
	for a given mode.
	(GET_MODE_COMPLEX_MODE): Likewise.
	* stor-layout.c (layout_type): For COMPLEX_TYPE, use the mode
	stored by build_complex_type and gfc_build_complex_type instead of
	trying to figure out the appropriate mode based on the size. Raise
	an assertion error, if the type was not set.
	* genmodes.c (struct mode_data): Add field for the complex type of
	the given type.
	(blank_mode): Likewise.
	(make_complex_modes): Remember the complex mode created in the
	base type.
	(emit_mode_complex): Write out the mode_complex array to map a
	type mode to the complex version.
	(emit_insn_modes_c): Likewise.
	* tree.c (build_complex_type): Set the complex type to use before
	calling layout_type.
	* config/rs6000/rs6000.c (rs6000_hard_regno_nregs_internal): Add
	support for __float128 complex datatypes.
	(rs6000_hard_regno_mode_ok): Likewise.
	(rs6000_setup_reg_addr_masks): Likewise.
	(rs6000_complex_function_value): Likewise.
	* config/rs6000/rs6000.h (FLOAT128_IEEE_P): Likewise.
	__float128 and __ibm128 complex.
	(FLOAT128_IBM_P): Likewise.
	(ALTIVEC_ARG_MAX_RETURN): Likewise.
	* doc/extend.texi (Additional Floating Types): Document that
	-mfloat128 must be used to enable __float128.  Document complex
	__float128 and __ibm128 support.

[gcc/testsuite]
2016-06-22  Michael Meissner  <meissner@linux.vnet.ibm.com>

	Back port from trunk
	2016-05-02  Michael Meissner  <meissner@linux.vnet.ibm.com>

	* gcc.target/powerpc/float128-complex-1.c: New tests for complex
	__float128.
	* gcc.target/powerpc/float128-complex-2.c: Likewise.

-- 
Michael Meissner, IBM
IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA
email: meissner@linux.vnet.ibm.com, phone: +1 (978) 899-4797