Re: [PING] [PATCH] [MSP430] PR79242: Implement Complex Partial Integers

[Jeff Law <law@redhat.com>]

On 02/08/2018 09:54 AM, Jozef Lawrynowicz wrote:
> ping x1
> 
> Complex Partial Integers are unimplemented, resulting in an ICE when
> attempting to use them. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79242
> This results in GCC7/8 for msp430-elf failing to build.
> 
> typedef _Complex __int20 C;
> 
> C
> foo (C x, C y)
> {
>   return x + y;
> }
> 
> (Thanks Jakub - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79242#c2)
> 
> ../../gcc/testsuite/gcc.target/msp430/pr79242.c: In function 'foo':
> ../../gcc/testsuite/gcc.target/msp430/pr79242.c:8:1: internal compiler
> error: in make_decl_rtl, at varasm.c:1304
>  foo (C x, C y)
>  ^~~
> 0xc07b29 make_decl_rtl(tree_node*)
>         ../../gcc/varasm.c:1303
> 0x67523c set_parm_rtl(tree_node*, rtx_def*)
>         ../../gcc/cfgexpand.c:1274
> 0x79ffb9 expand_function_start(tree_node*)
>         ../../gcc/function.c:5166
> 0x6800e1 execute
>         ../../gcc/cfgexpand.c:6250
> 
> The attached patch defines a new complex mode for PARTIAL_INT.
> You may notice that genmodes.c:complex_class returns MODE_COMPLEX_INT for
> MODE_PARTIAL_INT rather than MODE_COMPLEX_PARTIAL_INT. I reviewed the uses of
> MODE_COMPLEX_INT and it doesn't looked like a Complex Partial Int requires any
> different behaviour to MODE_COMPLEX_INT.
> 
> msp430_hard_regno_nregs now returns 2 for CPSImode, but I feel like this may be
> better handled in the front-end. PSImode is already defined to only use 1
> register, so for a CPSI shouldn't the front-end should be able to work out that
> double the amount of registers are required? Thoughts?
> Without the definition for CPSI in msp430_hard_regno_nregs,
> rtlanal.c:subreg_get_info thinks that a CPSI requires 4 registers of size 2,
> instead of 2 registers of size 4.
> 
> Successfully bootstrapped and tested for c,c++,fortran,lto,objc on
> x86_64-pc-linux-gnu with no regressions on gcc-7-branch.
> 
> With this patch gcc-7-branch now builds for msp430-elf. A further bug prevents
> trunk from building for msp430-elf.
> 
> If the attached patch is acceptable, I would appreciate if someone would commit
> it for me (to trunk and gcc-7-branch), as I do not have write access.
> 
> 
> 0001-Add-support-for-Complex-Partial-Integers-CPSImode.patch
> 
> 
> From 31d8554ebb6afeb2d8f235cf3d3c262236aa5e32 Mon Sep 17 00:00:00 2001
> From: Jozef Lawrynowicz <jozefl.gcc@gmail.com>
> Date: Fri, 12 Jan 2018 13:23:40 +0000
> Subject: [PATCH] Add support for Complex Partial Integers - CPSImode
> 
> 2018-01-XX  Jozef Lawrynowicz <jozefl.gcc@gmail.com>
> 
> gcc/
>   PR target/79242
>   * machmode.def: Define a complex mode for PARTIAL_INT.
>   * genmodes.c (complex_class): Return MODE_COMPLEX_INT for
>     MODE_PARTIAL_INT.
>   * doc/rtl.texi: Document CSPImode.
>   * config/msp430/msp430.c (msp430_hard_regno_nregs): Add CPSImode
>     handling.
>     (msp430_hard_regno_nregs_with_padding): Likewise.
> 
> gcc/testsuite/
>   PR target/79242
>   * gcc.target/msp430/pr79242.c: New test.
Thanks.  Installed.

jeff