They only have one result.
This also resolves the harmless typo, that they used each others Proj enums.

It pops a value from the stack, so this memory access should be represented in the graph.

The node must use the mode of the floating point register class, irrespective of the mode of the loaded constant.

IncSP can only have %esp assigned.

arm, be, ia32, sparc: Do not go on with peephole optimization of IncSP, when be_peephole_IncSP_IncSP() succeeded.

The current IncSP was removed in this case and we now would operate on its predecessor IncSP.
This is wrong, e.g. when asking for currently free registers.
This corrects backend/incsp_pop.c, which was broken on ia32.
It was wrongly assumed that a certain register was free and could be used to turn an IncSP into a Pop.

Otherwise the frontend has to do this after asking the backend for its parameters, which is quite awkward.

Duplicate Projs are a problem when CSE is off, e.g. -O0.

PC relative relocations need %rip as base register so we cannot match
anything else for base.

Calls+Jumps really use PC relative addresses even if they look the same
in the assembler. Create an immediate kind for that, this allows a
slightly simpler bemit_entity().

The following be_peephole_exchange() has a stricter check, i.e. same mode instead of only not mode_T.

It is like new_r_Proj(), but the mode is determined automatically from the out requirement of the predecessor.
This probably resolves some mode mismatches in untested code paths -- AMD64 backend and SPARC hard float, I'm looking at you!

Now register requirements always have have a register class.
This is more consistent and removes some null pointer checks.

Nodes without requirements are never operands of a {Copy,}Keep.

match_requirement() cannot be called with a requirement without a register class.

Now we can use things, which get initialized for the middle end, e.g. modes.

The caller of be_opt_register() calls it, too.