simplify handling of anonymous entry blocks; fixes #948

3 files changed, 44 insertions, 15 deletions

diff --git a/src/analyzer.js b/src/analyzer.js
index b1991c3f..6ed55414 100644
--- a/src/analyzer.js
+++ b/src/analyzer.js
@@ -9,7 +9,6 @@ var VAR_NATIVIZED = 'nativized';
 var VAR_EMULATED = 'emulated';
 
 var ENTRY_IDENT = toNiceIdent('%0');
-var ENTRY_IDENT_IDS = set(0, 1); // XXX
 
 function recomputeLines(func) {
   func.lines = func.labels.map(function(label) { return label.lines }).reduce(concatenator, []);
@@ -1326,14 +1325,14 @@ function analyzer(data, sidePass) {
         func.labelsDict = {};
         func.labelIds = {};
         func.labelIdsInverse = {};
-        func.labelIds[toNiceIdent('%0')] = 0;
+        func.labelIds[toNiceIdent('%0')] = 1;
         func.labelIdsInverse[0] = toNiceIdent('%0');
-        func.labelIds[toNiceIdent('%1')] = 1;
-        func.labelIdsInverse[1] = toNiceIdent('%1');
         func.labelIdCounter = 2;
         func.labels.forEach(function(label) {
-          func.labelIds[label.ident] = func.labelIdCounter++;
-          func.labelIdsInverse[func.labelIdCounter-1] = label.ident;
+          if (!(label.ident in func.labelIds)) {
+            func.labelIds[label.ident] = func.labelIdCounter++;
+            func.labelIdsInverse[func.labelIdCounter-1] = label.ident;
+          }
         });
 
         // Minify label ids to numeric ids.
@@ -1368,16 +1367,12 @@ function analyzer(data, sidePass) {
           }
         });
 
-        // The entry might not have an explicit label, and there is no consistent naming convention for it - it can be %0 or %1
-        // So we need to handle that in a special way here.
         function getActualLabelId(labelId) {
           if (func.labelsDict[labelId]) return labelId;
-          if (labelId in ENTRY_IDENT_IDS) {
-            labelId = func.labelIds[ENTRY_IDENT];
-            assert(func.labelsDict[labelId]);
-            return labelId;
-          }
-          return null;
+          // If not present, it must be a surprisingly-named entry (or undefined behavior, in which case, still ok to use the entry)
+          labelId = func.labelIds[ENTRY_IDENT];
+          assert(func.labelsDict[labelId]);
+          return labelId;
         }
 
         // Basic longjmp support, see library.js setjmp/longjmp
@@ -1573,7 +1568,7 @@ function analyzer(data, sidePass) {
       }
       item.functions.forEach(function(func) {
         dprint('relooping', "// relooping function: " + func.ident);
-        func.block = makeBlock(func.labels, [toNiceIdent(func.labels[0].ident)], func.labelsDict, func.forceEmulated);
+        func.block = makeBlock(func.labels, [func.labels[0].ident], func.labelsDict, func.forceEmulated);
       });
 
       return finish();
diff --git a/tests/cases/entry2.ll b/tests/cases/entry2.ll
new file mode 100644
index 00000000..75b266c7
--- /dev/null
+++ b/tests/cases/entry2.ll
@@ -0,0 +1,32 @@
+; ModuleID = '/tmp/tmpKnA2D3/a.out.bc'
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32-S128"
+target triple = "i386-pc-linux-gnu"
+
+@.str = private unnamed_addr constant [11 x i8] c"getgid=%d\0A\00", align 1
+@.str1 = private unnamed_addr constant [6 x i8] c"f=%d\0A\00", align 1
+
+define internal i32 @_Z1fii(i32, i32) noinline {
+  %3 = tail call i32 @getgid()
+  %4 = icmp eq i32 %3, 0
+  br i1 %4, label %7, label %5
+
+; <label>:5                                       ; preds = %2
+  %6 = tail call i32 @getgid()
+  br label %7
+
+; <label>:7                                       ; preds = %5, %2
+  %.0 = phi i32 [ 0, %5 ], [ 1, %2 ]
+  ret i32 %.0
+}
+
+declare i32 @getgid()
+
+define i32 @main() {
+  %1 = tail call i32 @getgid()
+  %2 = tail call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([11 x i8]* @.str, i32 0, i32 0), i32 %1)
+  %3 = tail call i32 @_Z1fii(i32 undef, i32 undef)
+  %4 = tail call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([6 x i8]* @.str1, i32 0, i32 0), i32 %3)
+  ret i32 0
+}
+
+declare i32 @printf(i8* nocapture, ...) nounwind
diff --git a/tests/cases/entry2.txt b/tests/cases/entry2.txt
new file mode 100644
index 00000000..37642b36
--- /dev/null
+++ b/tests/cases/entry2.txt
@@ -0,0 +1,2 @@
+getgid=0
+f=1