"Writing an LLVM Compiler Backend" can be misinterpreted as meaning
"backend" in the sense of "using LLVM as a backend for your compiler for
your new language". This new name is less ambiguous.
As a bonus, this brings the title in line with the file name.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185377 91177308-0d34-0410-b5e6-96231b3b80d8
This patch modifies TableGen to generate a function in
${TARGET}GenInstrInfo.inc called getNamedOperandIdx(), which can be used
to look up indices for operands based on their names.
In order to activate this feature for an instruction, you must set the
UseNamedOperandTable bit.
For example, if you have an instruction like:
def ADD : TargetInstr <(outs GPR:$dst), (ins GPR:$src0, GPR:$src1)>;
You can look up the operand indices using the new function, like this:
Target::getNamedOperandIdx(Target::ADD, Target::OpName::dst) => 0
Target::getNamedOperandIdx(Target::ADD, Target::OpName::src0) => 1
Target::getNamedOperandIdx(Target::ADD, Target::OpName::src1) => 2
The operand names are case sensitive, so $dst and $DST are considered
different operands.
This change is useful for R600 which has instructions with a large number
of operands, many of which model single bit instruction configuration
values. These configuration bits are common across most instructions,
but may have a different operand index depending on the instruction type.
It is useful to have a convenient way to look up the operand indices,
so these bits can be generically set on any instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184879 91177308-0d34-0410-b5e6-96231b3b80d8
Also update the documentation since Sparc is the nicest backend, and
used as an example in WritingAnLLVMBackend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177835 91177308-0d34-0410-b5e6-96231b3b80d8
against the developer policy to include this sort of thing as SVN blame
already captures this in a far more fine-grained way.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172109 91177308-0d34-0410-b5e6-96231b3b80d8
I actually made a think-o when writing this FIXME since I wrote LangRef
but it should actually have said WritingAnLLVMBackend.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171293 91177308-0d34-0410-b5e6-96231b3b80d8
