R600/SI: Change formatting of printed registers.

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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194443 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 64 insertions, 2 deletions

diff --git a/lib/Target/R600/InstPrinter/AMDGPUInstPrinter.cpp b/lib/Target/R600/InstPrinter/AMDGPUInstPrinter.cpp
index a777802383..99e1377a65 100644
--- a/lib/Target/R600/InstPrinter/AMDGPUInstPrinter.cpp
+++ b/lib/Target/R600/InstPrinter/AMDGPUInstPrinter.cpp
@@ -23,6 +23,63 @@ void AMDGPUInstPrinter::printInst(const MCInst *MI, raw_ostream &OS,
   printAnnotation(OS, Annot);
 }
 
+void AMDGPUInstPrinter::printRegOperand(unsigned reg, raw_ostream &O) {
+  switch (reg) {
+  case AMDGPU::VCC:
+    O << "vcc";
+    return;
+  case AMDGPU::SCC:
+    O << "scc";
+    return;
+  case AMDGPU::EXEC:
+    O << "exec";
+    return;
+  case AMDGPU::M0:
+    O << "m0";
+    return;
+  default:
+    break;
+  }
+
+  // It's seems there's no way to use SIRegisterInfo here, and dealing with the
+  // giant enum of all the different shifted sets of registers is pretty
+  // unmanagable, so parse the name and reformat it to be prettier.
+  StringRef Name(getRegisterName(reg));
+
+  std::pair<StringRef, StringRef> Split = Name.split('_');
+  StringRef SubRegName = Split.first;
+  StringRef Rest = Split.second;
+
+  if (SubRegName.size() <= 4) { // Must at least be as long as "SGPR"/"VGPR".
+    O << Name;
+    return;
+  }
+
+  unsigned RegIndex;
+  StringRef RegIndexStr = SubRegName.drop_front(4);
+
+  if (RegIndexStr.getAsInteger(10, RegIndex)) {
+    O << Name;
+    return;
+  }
+
+  if (SubRegName.front() == 'V')
+    O << 'v';
+  else if (SubRegName.front() == 'S')
+    O << 's';
+  else {
+    O << Name;
+    return;
+  }
+
+  if (Rest.empty()) // Only 1 32-bit register
+    O << RegIndex;
+  else {
+    unsigned NumReg = Rest.count('_') + 2;
+    O << '[' << RegIndex << ':' << (RegIndex + NumReg - 1) << ']';
+  }
+}
+
 void AMDGPUInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
                                      raw_ostream &O) {
 
@@ -30,8 +87,12 @@ void AMDGPUInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
   if (Op.isReg()) {
     switch (Op.getReg()) {
     // This is the default predicate state, so we don't need to print it.
-    case AMDGPU::PRED_SEL_OFF: break;
-    default: O << getRegisterName(Op.getReg()); break;
+    case AMDGPU::PRED_SEL_OFF:
+      break;
+
+    default:
+      printRegOperand(Op.getReg(), O);
+      break;
     }
   } else if (Op.isImm()) {
     O << Op.getImm();
diff --git a/lib/Target/R600/InstPrinter/AMDGPUInstPrinter.h b/lib/Target/R600/InstPrinter/AMDGPUInstPrinter.h
index 3524b30935..77af9425c5 100644
--- a/lib/Target/R600/InstPrinter/AMDGPUInstPrinter.h
+++ b/lib/Target/R600/InstPrinter/AMDGPUInstPrinter.h
@@ -32,6 +32,7 @@ public:
   virtual void printInst(const MCInst *MI, raw_ostream &O, StringRef Annot);
 
 private:
+  void printRegOperand(unsigned RegNo, raw_ostream &O);
   void printOperand(const MCInst *MI, unsigned OpNo, raw_ostream &O);
   void printInterpSlot(const MCInst *MI, unsigned OpNum, raw_ostream &O);
   void printMemOperand(const MCInst *MI, unsigned OpNo, raw_ostream &O);