[Bug target/85261] __builtin_arm_set_fpscr ICEs with constant input

[thopre01 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85261

--- Comment #5 from Thomas Preud'homme <thopre01 at gcc dot gnu.org> ---
Author: thopre01
Date: Wed Apr 18 11:42:10 2018
New Revision: 259465

URL: https://gcc.gnu.org/viewcvs?rev=259465&root=gcc&view=rev
Log:
[ARM] Fix PR85261: ICE with FPSCR setter builtin

Instruction pattern for setting the FPSCR expects the input value to be
in a register. However, __builtin_arm_set_fpscr expander does not ensure
that this is the case and as a result GCC ICEs when the builtin is
called with a constant literal.

This commit fixes the builtin to force the input value into a register.
It also remove the unneeded volatile in the existing fpscr test and
fixes the function prototype.

2018-04-18  Thomas Preud'homme  <thomas.preudhomme@arm.com>

    Backport from mainline
    2018-04-11  Thomas Preud'homme  <thomas.preudhomme@arm.com>

    gcc/
    PR target/85261
    * config/arm/arm-builtins.c (arm_expand_builtin): Force input operand
    into register.

    gcc/testsuite/
    PR target/85261
    * gcc.target/arm/fpscr.c: Add call to __builtin_arm_set_fpscr with
    literal value.  Expect 2 MCR instruction.  Fix function prototype.
    Remove volatile keyword.

Modified:
    branches/gcc-7-branch/gcc/ChangeLog
    branches/gcc-7-branch/gcc/config/arm/arm-builtins.c
    branches/gcc-7-branch/gcc/testsuite/ChangeLog
    branches/gcc-7-branch/gcc/testsuite/gcc.target/arm/fpscr.c