commit 87d410c8dbe3142feef461e6a23d8f7dd5663570
author Olli Etuaho <oetuaho@nvidia.com> Mon Sep 05 13:33:26 2016 +0300
committer Commit Bot <commit-bot@chromium.org> Mon Sep 12 14:21:48 2016 +0000
tree 0b58c323588def303ab961ea1f63033bca7bd00b
parent a223430c3d8478f13fd800f84ba88de2dd88b9c1

Disallow multiple locations on output variables

GLSL ES specs from version 3.00 to 3.20 all mention that output layout
location qualifier may appear at most once within a declaration.
Enforce this rule when parsing shaders.

Also set max draw buffers to 8 when compiling GLSL ES >= 3.00 in the
qualification order tests and shader translator sample, so that
parsing locations > 0 will succeed.

BUG=angleproject:1505
TEST=angle_unittests

Change-Id: I50fe409041385f5e10e695f43dc3a572433e9772
Reviewed-on: https://chromium-review.googlesource.com/381211
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>

src/compiler/translator/BaseTypes.h

diff --git a/src/compiler/translator/BaseTypes.h b/src/compiler/translator/BaseTypes.h
index 78e06b3..0919955 100644
--- a/src/compiler/translator/BaseTypes.h
+++ b/src/compiler/translator/BaseTypes.h
@@ -387,6 +387,7 @@
 struct TLayoutQualifier
 {
     int location;
+    unsigned int locationsSpecified;
     TLayoutMatrixPacking matrixPacking;
     TLayoutBlockStorage blockStorage;
 
@@ -398,6 +399,7 @@
         TLayoutQualifier layoutQualifier;
 
         layoutQualifier.location = -1;
+        layoutQualifier.locationsSpecified = 0;
         layoutQualifier.matrixPacking = EmpUnspecified;
         layoutQualifier.blockStorage = EbsUnspecified;
 

src/compiler/translator/ParseContext.cpp

diff --git a/src/compiler/translator/ParseContext.cpp b/src/compiler/translator/ParseContext.cpp
index fc3c2c5..9a08ddf 100644
--- a/src/compiler/translator/ParseContext.cpp
+++ b/src/compiler/translator/ParseContext.cpp
@@ -2935,6 +2935,7 @@
         else
         {
             qualifier.location = intValue;
+            qualifier.locationsSpecified = 1;
         }
     }
     else if (qualifierType == "local_size_x")

src/compiler/translator/QualifierTypes.cpp

diff --git a/src/compiler/translator/QualifierTypes.cpp b/src/compiler/translator/QualifierTypes.cpp
index 27d73aa..b785627 100644
--- a/src/compiler/translator/QualifierTypes.cpp
+++ b/src/compiler/translator/QualifierTypes.cpp
@@ -22,6 +22,7 @@
     if (rightQualifier.location != -1)
     {
         joinedQualifier.location = rightQualifier.location;
+        ++joinedQualifier.locationsSpecified;
     }
     if (rightQualifier.matrixPacking != EmpUnspecified)
     {
@@ -98,6 +99,9 @@
     bool layoutFound        = false;
     bool interpolationFound = false;
 
+    unsigned int locationsSpecified = 0;
+    bool isOut                      = false;
+
     // The iteration starts from one since the first qualifier only reveals the scope of the
     // expression. It is inserted first whenever the sequence gets created.
     for (size_t i = 1; i < qualifiers.size(); ++i)
@@ -132,6 +136,9 @@
                     return true;
                 }
                 layoutFound = true;
+                const TLayoutQualifier &currentQualifier =
+                    static_cast<const TLayoutQualifierWrapper *>(qualifiers[i])->getQualifier();
+                locationsSpecified += currentQualifier.locationsSpecified;
                 break;
             }
             case QtInterpolation:
@@ -153,6 +160,10 @@
                 // repetitions.
                 TQualifier currentQualifier =
                     static_cast<const TStorageQualifierWrapper *>(qualifiers[i])->getQualifier();
+                if (currentQualifier == EvqVertexOut || currentQualifier == EvqFragmentOut)
+                {
+                    isOut = true;
+                }
                 for (size_t j = 1; j < i; ++j)
                 {
                     if (qualifiers[j]->getType() == QtStorage)
@@ -175,6 +186,15 @@
         }
     }
 
+    if (locationsSpecified > 1 && isOut)
+    {
+        // GLSL ES 3.00.6 section 4.3.8.2 Output Layout Qualifiers
+        // GLSL ES 3.10 section 4.4.2 Output Layout Qualifiers
+        // "The qualifier may appear at most once within a declaration."
+        *errorMessage = "Output layout location specified multiple times.";
+        return true;
+    }
+
     return false;
 }