simply compiler by always pushing back phis

2 files changed, 35 insertions, 100 deletions

diff --git a/src/analyzer.js b/src/analyzer.js
index cbb4f28e..23f56712 100644
--- a/src/analyzer.js
+++ b/src/analyzer.js
@@ -1278,89 +1278,44 @@ function analyzer(data, sidePass) {
           recomputeLines(func);
         }
 
-        if (!MICRO_OPTS) {
-          // 'Emulate' phis, by doing an if where the phi appears in the .ll. For this
-          // we need __lastLabel__.
-          func.needsLastLabel = false;
-          func.labels.forEach(function(label) {
-            var phis = [];
-            label.lines.forEach(function(phi) {
-              if (phi.intertype == 'phi') {
-                for (var i = 0; i < phi.params.length; i++) {
-                  var sourceLabelId = getActualLabelId(phi.params[i].label);
-                  if (sourceLabelId) {
-                    var sourceLabel = func.labelsDict[sourceLabelId];
-                    var lastLine = sourceLabel.lines.slice(-1)[0];
-                    assert(lastLine.intertype in LLVM.PHI_REACHERS, 'Only some can lead to labels with phis:' + [func.ident, label.ident, lastLine.intertype]);
-                    lastLine.currLabelId = sourceLabelId;
-                  }
-                }
-                phis.push(phi);
-                func.needsLastLabel = true;
-              }
-            });
+        // Properly implement phis, by pushing them back into the branch
+        // that leads to here. We will only have the |var| definition in this location.
 
-            if (phis.length >= 2) {
-              // Multiple phis have the semantics that they all occur 'in parallel', i.e., changes to
-              // a variable that is the result of a phi should *not* affect the other results. We must
-              // therefore be careful!
-              phis[phis.length-1].postSet = '; /* post-phi: */';
-              for (var i = 0; i < phis.length-1; i++) {
-                var ident = phis[i].assignTo;
-                var phid = ident+'$phi'
-                phis[phis.length-1].postSet += ident + '=' + phid + ';';
-                phis[i].assignTo = phid;
-                func.variables[phid] = {
-                  ident: phid,
-                  type: func.variables[ident].type,
-                  origin: func.variables[ident].origin,
-                  lineNum: func.variables[ident].lineNum,
-                  uses: 1,
-                  impl: VAR_EMULATED
-                };
-              }
-            }
-          });
-        } else {
-          // MICRO_OPTS == 1: Properly implement phis, by pushing them back into the branch
-          // that leads to here. We will only have the |var| definition in this location.
-
-          // First, push phis back
-          func.labels.forEach(function(label) {
-            label.lines.forEach(function(phi) {
-              if (phi.intertype == 'phi') {
-                for (var i = 0; i < phi.params.length; i++) {
-                  var param = phi.params[i];
-                  assert(param.label);
-                  var sourceLabelId = getActualLabelId(param.label);
-                  if (sourceLabelId) {
-                    var sourceLabel = func.labelsDict[sourceLabelId];
-                    var lastLine = sourceLabel.lines.slice(-1)[0];
-                    assert(lastLine.intertype in LLVM.PHI_REACHERS, 'Only some can lead to labels with phis:' + [func.ident, label.ident, lastLine.intertype]);
-                    if (!lastLine.phi) {
-                      lastLine.phi = true;
-                      assert(!lastLine.dependent);
-                      lastLine.dependent = {
-                        intertype: 'phiassigns',
-                        params: []
-                      };
+        // First, push phis back
+        func.labels.forEach(function(label) {
+          label.lines.forEach(function(phi) {
+            if (phi.intertype == 'phi') {
+              for (var i = 0; i < phi.params.length; i++) {
+                var param = phi.params[i];
+                assert(param.label);
+                var sourceLabelId = getActualLabelId(param.label);
+                if (sourceLabelId) {
+                  var sourceLabel = func.labelsDict[sourceLabelId];
+                  var lastLine = sourceLabel.lines.slice(-1)[0];
+                  assert(lastLine.intertype in LLVM.PHI_REACHERS, 'Only some can lead to labels with phis:' + [func.ident, label.ident, lastLine.intertype]);
+                  if (!lastLine.phi) {
+                    lastLine.phi = true;
+                    assert(!lastLine.dependent);
+                    lastLine.dependent = {
+                      intertype: 'phiassigns',
+                      params: []
                     };
-                    lastLine.dependent.params.push({
-                      intertype: 'phiassign',
-                      ident: phi.assignTo,
-                      value: param.value,
-                      targetLabel: label.ident
-                    });
-                  }
+                  };
+                  lastLine.dependent.params.push({
+                    intertype: 'phiassign',
+                    ident: phi.assignTo,
+                    value: param.value,
+                    targetLabel: label.ident
+                  });
                 }
-                // The assign to phi is now just a var
-                phi.intertype = 'var';
-                phi.ident = phi.assignTo;
-                phi.assignTo = null;
               }
-            });
+              // The assign to phi is now just a var
+              phi.intertype = 'var';
+              phi.ident = phi.assignTo;
+              phi.assignTo = null;
+            }
           });
-        }
+        });
       });
       this.forwardItem(item, 'StackAnalyzer');
     }
diff --git a/src/jsifier.js b/src/jsifier.js
index 89930918..6cbe8b88 100644
--- a/src/jsifier.js
+++ b/src/jsifier.js
@@ -558,9 +558,6 @@ function JSify(data, functionsOnly, givenFunctions) {
         if (CLOSURE_ANNOTATIONS) func.JS += '/** @type {number} */';
         func.JS += '  var __label__;\n';
       }
-      if (func.needsLastLabel) {
-        func.JS += '  var __lastLabel__ = null;\n';
-      }
 
       // Walk function blocks and generate JS
       function walkBlock(block, indent) {
@@ -751,7 +748,7 @@ function JSify(data, functionsOnly, givenFunctions) {
   makeFuncLineActor('noop', function(item) {
     return ';';
   });
-  makeFuncLineActor('var', function(item) { // assigns into phis become simple vars when MICRO_OPTS
+  makeFuncLineActor('var', function(item) { // assigns into phis become simple vars
     return 'var ' + item.ident + ';';
   });
   makeFuncLineActor('store', function(item) {
@@ -792,11 +789,8 @@ function JSify(data, functionsOnly, givenFunctions) {
     return label;
   }
 
-  function makeBranch(label, lastLabel, labelIsVariable) {
+  function makeBranch(label, lastLabel, labelIsVariable) { // lastLabel is deprecated
     var pre = '';
-    if (!MICRO_OPTS && lastLabel) {
-      pre = '__lastLabel__ = ' + getLabelId(lastLabel) + '; ';
-    }
     if (label[0] == 'B') {
       assert(!labelIsVariable, 'Cannot handle branches to variables with special branching options');
       var parts = label.split('|');
@@ -1064,20 +1058,6 @@ function JSify(data, functionsOnly, givenFunctions) {
       return RuntimeGenerator.stackAlloc(getFastValue(calcAllocatedSize(item.allocatedType), '*', item.allocatedNum));
     }
   });
-  makeFuncLineActor('phi', function(item) {
-    var params = item.params;
-    assert(!MICRO_OPTS);
-    function makeOne(i) {
-      if (i === params.length-1) {
-        return finalizeLLVMParameter(params[i].value);
-      }
-      return '__lastLabel__ == ' + getLabelId(params[i].label) + ' ? ' + 
-                                   finalizeLLVMParameter(params[i].value) + ' : (' + makeOne(i+1) + ')';
-    }
-    var ret = makeOne(0);
-    if (item.postSet) ret += item.postSet;
-    return ret;
-  });
 
   makeFuncLineActor('mathop', processMathop);