X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=docs%2FCodeGenerator.rst;h=d54df0f6f4b242408be4ea7da114b08e6757fdaf;hb=1b0dc64919e947bb4f4677b138c734e33061f7c4;hp=cafa93e46a5facf5f204758301c2397d5e45cd60;hpb=91cb694fd7473fc95d0e0b6f5c6bd52818339e02;p=oota-llvm.git diff --git a/docs/CodeGenerator.rst b/docs/CodeGenerator.rst index cafa93e46a5..d54df0f6f4b 100644 --- a/docs/CodeGenerator.rst +++ b/docs/CodeGenerator.rst @@ -1,5 +1,3 @@ -.. _code_generator: - ========================================== The LLVM Target-Independent Code Generator ========================================== @@ -17,6 +15,8 @@ The LLVM Target-Independent Code Generator .partial { background-color: #F88017 } .yes { background-color: #0F0; } .yes:before { content: "Y" } + .na { background-color: #6666FF; } + .na:before { content: "N/A" } .. contents:: @@ -285,12 +285,10 @@ The ``TargetInstrInfo`` class ----------------------------- The ``TargetInstrInfo`` class is used to describe the machine instructions -supported by the target. It is essentially an array of ``TargetInstrDescriptor`` -objects, each of which describes one instruction the target -supports. Descriptors define things like the mnemonic for the opcode, the number -of operands, the list of implicit register uses and defs, whether the -instruction has certain target-independent properties (accesses memory, is -commutable, etc), and holds any target-specific flags. +supported by the target. Descriptions define things like the mnemonic for +the opcode, the number of operands, the list of implicit register uses and defs, +whether the instruction has certain target-independent properties (accesses +memory, is commutable, etc), and holds any target-specific flags. The ``TargetFrameInfo`` class ----------------------------- @@ -1040,6 +1038,24 @@ for your target. It has the following strengths: are used to manipulate the input immediate (in this case, take the high or low 16-bits of the immediate). +* When using the 'Pat' class to map a pattern to an instruction that has one + or more complex operands (like e.g. `X86 addressing mode`_), the pattern may + either specify the operand as a whole using a ``ComplexPattern``, or else it + may specify the components of the complex operand separately. The latter is + done e.g. for pre-increment instructions by the PowerPC back end: + + :: + + def STWU : DForm_1<37, (outs ptr_rc:$ea_res), (ins GPRC:$rS, memri:$dst), + "stwu $rS, $dst", LdStStoreUpd, []>, + RegConstraint<"$dst.reg = $ea_res">, NoEncode<"$ea_res">; + + def : Pat<(pre_store GPRC:$rS, ptr_rc:$ptrreg, iaddroff:$ptroff), + (STWU GPRC:$rS, iaddroff:$ptroff, ptr_rc:$ptrreg)>; + + Here, the pair of ``ptroff`` and ``ptrreg`` operands is matched onto the + complex operand ``dst`` of class ``memri`` in the ``STWU`` instruction. + * While the system does automate a lot, it still allows you to write custom C++ code to match special cases if there is something that is hard to express. @@ -1732,6 +1748,8 @@ This section of the document explains features or design decisions that are specific to the code generator for a particular target. First we start with a table that summarizes what features are supported by each target. +.. _target-feature-matrix: + Target Feature Matrix --------------------- @@ -1746,12 +1764,14 @@ the key: :raw-html:`
Unknown | ` +:raw-html:`Not Applicable | ` :raw-html:`No support | ` :raw-html:`Partial Support | ` :raw-html:`Complete Support | ` :raw-html:`||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` :raw-html:` | ` @@ -1771,9 +1791,10 @@ Here is the table: :raw-html:` | MBlaze | ` :raw-html:`MSP430 | ` :raw-html:`Mips | ` -:raw-html:`PTX | ` +:raw-html:`NVPTX | ` :raw-html:`PowerPC | ` :raw-html:`Sparc | ` +:raw-html:`SystemZ | ` :raw-html:`X86 | ` :raw-html:`XCore | ` :raw-html:`` :raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:`` :raw-html:` |
` :raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` :raw-html:` | ` :raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:`` :raw-html:` |
` :raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ||||
` :raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ||||
` :raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` :raw-html:` | ` :raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:`` :raw-html:` |
` :raw-html:` | ` :raw-html:` | ` -:raw-html:` | ` +:raw-html:` | ` :raw-html:` | ` :raw-html:` | ` +:raw-html:` | ` :raw-html:` | * | ` :raw-html:`` :raw-html:` | Description | ` :raw-html:`` :raw-html:`||||
``double`` | ` -:raw-html:`If enabled, the map_f64_to_f32 directive is disabled in the PTX output, allowing native double-precision arithmetic | ` +:raw-html:`sm_20 | ` +:raw-html:`Set shader model/compute capability to 2.0 | ` :raw-html:`|||||||||||
``no-fma`` | ` -:raw-html:`Disable generation of Fused-Multiply Add instructions, which may be beneficial for some devices | ` +:raw-html:`sm_21 | ` +:raw-html:`Set shader model/compute capability to 2.1 | ` :raw-html:`|||||||||||
``smxy / computexy`` | ` -:raw-html:`Set shader model/compute capability to x.y, e.g. sm20 or compute13 | ` +:raw-html:`sm_30 | ` +:raw-html:`Set shader model/compute capability to 3.0 | ` +:raw-html:`|||||||||||
sm_35 | ` +:raw-html:`Set shader model/compute capability to 3.5 | ` +:raw-html:`|||||||||||||
ptx30 | ` +:raw-html:`Target PTX 3.0 | ` +:raw-html:`|||||||||||||
ptx31 | ` +:raw-html:`Target PTX 3.1 | ` :raw-html:`