Add PPC instruction record forms and associated query functions

This is prep. work for the implementation of optimizeCompare. Many PPC
instructions have 'record' forms (in almost all cases, this means that the RC
bit is set) that cause the result of the instruction to be compared with zero,
and the result of that comparison saved in a predefined condition register. In
order to add the record forms of the instructions without too much
copy-and-paste, the relevant functions have been refactored into multiclasses
which define both the record and normal forms.

Also, two TableGen-generated mapping functions have been added which allow
querying the instruction code for the record form given the normal form (and
vice versa).

No functionality change intended.

llvm-svn: 179356

1 files changed, 37 insertions, 1 deletions

diff --git a/llvm/lib/Target/PowerPC/PPC.td b/llvm/lib/Target/PowerPC/PPC.td
index 389216278ee..649ffc1abea 100644
--- a/llvm/lib/Target/PowerPC/PPC.td
+++ b/llvm/lib/Target/PowerPC/PPC.td
@@ -95,6 +95,43 @@ def FeatureQPX       : SubtargetFeature<"qpx","HasQPX", "true",
 // VSX          p7                 vector-scalar instruction set
 
 //===----------------------------------------------------------------------===//
+// Classes used for relation maps.
+//===----------------------------------------------------------------------===//
+// RecFormRel - Filter class used to relate non-record-form instructions with
+// their record-form variants.
+class RecFormRel;
+
+//===----------------------------------------------------------------------===//
+// Relation Map Definitions.
+//===----------------------------------------------------------------------===//
+
+def getRecordFormOpcode : InstrMapping {
+  let FilterClass = "RecFormRel";
+  // Instructions with the same BaseName and Interpretation64Bit values
+  // form a row.
+  let RowFields = ["BaseName", "Interpretation64Bit"];
+  // Instructions with the same RC value form a column.
+  let ColFields = ["RC"];
+  // The key column are the non-record-form instructions.
+  let KeyCol = ["0"];
+  // Value columns RC=1
+  let ValueCols = [["1"]];
+}
+
+def getNonRecordFormOpcode : InstrMapping {
+  let FilterClass = "RecFormRel";
+  // Instructions with the same BaseName and Interpretation64Bit values
+  // form a row.
+  let RowFields = ["BaseName", "Interpretation64Bit"];
+  // Instructions with the same RC value form a column.
+  let ColFields = ["RC"];
+  // The key column are the record-form instructions.
+  let KeyCol = ["1"];
+  // Value columns are RC=0
+  let ValueCols = [["0"]];
+}
+
+//===----------------------------------------------------------------------===//
 // Register File Description
 //===----------------------------------------------------------------------===//
 
@@ -216,7 +253,6 @@ def : ProcessorModel<"ppc64", G5Model,
                    FeatureFRSQRTE, FeatureSTFIWX,
                    Feature64Bit /*, Feature64BitRegs */]>;
 
-
 //===----------------------------------------------------------------------===//
 // Calling Conventions
 //===----------------------------------------------------------------------===//