[WebAssembly] Make CFG stackification independent of basic-block labels.

[oota-llvm.git] / lib / Target / WebAssembly / InstPrinter / WebAssemblyInstPrinter.cpp

diff --git a/lib/Target/WebAssembly/InstPrinter/WebAssemblyInstPrinter.cpp b/lib/Target/WebAssembly/InstPrinter/WebAssemblyInstPrinter.cpp
index f92a9d0c6615f2e99bfec7f408ebde2a8463d556..60e52015242336a936ba51fd8516b2a015951f18 100644 (file)
--- a/lib/Target/WebAssembly/InstPrinter/WebAssemblyInstPrinter.cpp
+++ b/lib/Target/WebAssembly/InstPrinter/WebAssemblyInstPrinter.cpp
@@ -16,6 +16,8 @@
 #include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
 #include "WebAssembly.h"
 #include "WebAssemblyMachineFunctionInfo.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/StringExtras.h"
 #include "llvm/MC/MCExpr.h"
 #include "llvm/MC/MCInst.h"
 #include "llvm/MC/MCInstrInfo.h"
@@ -33,7 +35,7 @@ using namespace llvm;
 WebAssemblyInstPrinter::WebAssemblyInstPrinter(const MCAsmInfo &MAI,
                                                const MCInstrInfo &MII,
                                                const MCRegisterInfo &MRI)
-    : MCInstPrinter(MAI, MII, MRI) {}
+    : MCInstPrinter(MAI, MII, MRI), ControlFlowCounter(0) {}
 
 void WebAssemblyInstPrinter::printRegName(raw_ostream &OS,
                                           unsigned RegNo) const {
@@ -59,6 +61,52 @@ void WebAssemblyInstPrinter::printInst(const MCInst *MI, raw_ostream &OS,
 
   // Print any added annotation.
   printAnnotation(OS, Annot);
+
+  if (CommentStream) {
+    // Observe any effects on the control flow stack, for use in annotating
+    // control flow label references.
+    switch (MI->getOpcode()) {
+    default:
+      break;
+    case WebAssembly::LOOP: {
+      // Grab the TopLabel value first so that labels print in numeric order.
+      uint64_t TopLabel = ControlFlowCounter++;
+      ControlFlowStack.push_back(std::make_pair(ControlFlowCounter++, false));
+      printAnnotation(OS, "label" + utostr(TopLabel) + ':');
+      ControlFlowStack.push_back(std::make_pair(TopLabel, true));
+      break;
+    }
+    case WebAssembly::BLOCK:
+      ControlFlowStack.push_back(std::make_pair(ControlFlowCounter++, false));
+      break;
+    case WebAssembly::END_LOOP:
+      ControlFlowStack.pop_back();
+      printAnnotation(
+          OS, "label" + utostr(ControlFlowStack.pop_back_val().first) + ':');
+      break;
+    case WebAssembly::END_BLOCK:
+      printAnnotation(
+          OS, "label" + utostr(ControlFlowStack.pop_back_val().first) + ':');
+      break;
+    }
+
+    // Annotate any control flow label references.
+    unsigned NumFixedOperands = Desc.NumOperands;
+    SmallSet<uint64_t, 8> Printed;
+    for (unsigned i = 0, e = MI->getNumOperands(); i < e; ++i) {
+      const MCOperandInfo &Info = Desc.OpInfo[i];
+      if (!(i < NumFixedOperands
+                ? (Info.OperandType == WebAssembly::OPERAND_BASIC_BLOCK)
+                : (Desc.TSFlags & WebAssemblyII::VariableOpImmediateIsLabel)))
+        continue;
+      uint64_t Depth = MI->getOperand(i).getImm();
+      if (!Printed.insert(Depth).second)
+        continue;
+      const auto &Pair = ControlFlowStack.rbegin()[Depth];
+      printAnnotation(OS, utostr(Depth) + ": " + (Pair.second ? "up" : "down") +
+                              " to label" + utostr(Pair.first));
+    }
+  }
 }
 
 static std::string toString(const APFloat &FP) {
@@ -100,7 +148,7 @@ void WebAssemblyInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
   } else if (Op.isImm()) {
     assert((OpNo < MII.get(MI->getOpcode()).getNumOperands() ||
             (MII.get(MI->getOpcode()).TSFlags &
-                     WebAssemblyII::VariableOpIsImmediate)) &&
+             WebAssemblyII::VariableOpIsImmediate)) &&
            "WebAssemblyII::VariableOpIsImmediate should be set for "
            "variable_ops immediate ops");
     if (MII.get(MI->getOpcode()).TSFlags &
@@ -117,7 +165,7 @@ void WebAssemblyInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,
   } else {
     assert((OpNo < MII.get(MI->getOpcode()).getNumOperands() ||
             (MII.get(MI->getOpcode()).TSFlags &
-                     WebAssemblyII::VariableOpIsImmediate)) &&
+             WebAssemblyII::VariableOpIsImmediate)) &&
            "WebAssemblyII::VariableOpIsImmediate should be set for "
            "variable_ops expr ops");
     assert(Op.isExpr() && "unknown operand kind in printOperand");