Ulrich Weigand ec8d1a5b72 Extend TableGen instruction selection matcher to improve handling
of complex instruction operands (e.g. address modes).

Currently, if a Pat pattern creates an instruction that has a complex
operand (i.e. one that consists of multiple sub-operands at the MI
level), this operand must match a ComplexPattern DAG pattern with the
correct number of output operands.

This commit extends TableGen to alternatively allow match a complex
operands against multiple separate operands at the DAG level.

This allows using Pat patterns to match pre-increment nodes like
pre_store (which must have separate operands at the DAG level) onto
an instruction pattern that uses a multi-operand memory operand,
like the following example on PowerPC (will be committed as a
follow-on patch):

  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.

Approved by Jakob Stoklund Olesen.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177428 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19 19:51:09 +00:00
..
2013-01-20 07:01:04 +00:00
2013-02-12 11:45:22 +00:00
2013-03-11 16:51:15 +00:00
2013-03-11 16:25:16 +00:00
2013-01-21 21:46:32 +00:00
2013-02-27 18:48:42 +00:00
2013-02-18 02:44:09 +00:00

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