SI_IF and SI_ELSE are terminators which also produce a value. For
these instructions ISel always inserts a COPY to move their value
to another basic block. This COPY ends up between SI_(IF|ELSE)
and the S_BRANCH* instruction at the end of the block.
This breaks MachineBasicBlock::getFirstTerminator() and also the
machine verifier which assumes that terminators are grouped together at
the end of blocks.
To solve this we coalesce the copy away right after ISel to make sure
there are no instructions in between terminators at the end of blocks.
llvm-svn: 207591
Print the range of registers used with a single letter prefix.
This better matches what the shader compiler produces and
is overall less obnoxious than concatenating all of the
subregister names together.
Instead of SGPR0, it will print s0. Instead of SGPR0_SGPR1,
it will print s[0:1] and so on.
There doesn't appear to be a straightforward way
to get the actual register info in the InstPrinter,
so this parses the generated name to print with the
new syntax.
The required test changes are pretty nasty, and register
matching regexes are now worse. Since there isn't a way to
add to a variable in FileCheck, some of the tests now don't
check the exact number of registers used, but I don't think that
will be a real problem.
llvm-svn: 194443