Unfold short-circuiting operators in loop conditions correctly

Sometimes short-circuiting operators need to be unfolded to if statements. If the unfolded operator is inside a loop condition or expression, it needs to be evaluated repeatedly inside the loop. Add logic to UnfoldShortCircuitToIf that can move or copy the unfolded part of loop conditions or expressions to inside the loop. The exact changes that need to be done depend on the type of the loop. For loops may require also moving the initializer to outside the loop. The unfolded expression inside a loop condition or expression is moved or copied to inside the loop on the first traversal of the loop node, and unfolding to if is deferred until a second traversal. This keeps the code relatively simple. BUG=angleproject:1167 TEST=WebGL 2 conformance tests, dEQP-GLES2.functional.shaders.*select_iteration_count* Change-Id: Ieffc0ea858186054378d387dca9aa64a5fa95137 Reviewed-on: https://chromium-review.googlesource.com/310230Reviewed-by: Corentin Wallez <cwallez@chromium.org> Reviewed-by: Zhenyao Mo <zmo@chromium.org> Tested-by: Olli Etuaho <oetuaho@nvidia.com>

Unfold short-circuiting operators in loop conditions correctly
3fed4306 · Olli Etuaho · 15c2ac30 · 3fed4306 · 3fed4306 · 3fed4306
Commit 3fed4306 authored Nov 02, 2015 by Olli Etuaho
Showing with 10 additions and 11 deletions

IntermNode.cpp src/compiler/translator/IntermNode.cpp +1 -1

IntermNode.h src/compiler/translator/IntermNode.h +9 -10

UnfoldShortCircuitToIf.cpp src/compiler/translator/UnfoldShortCircuitToIf.cpp +0 -0

No files found.
--- a/src/compiler/translator/IntermNode.cpp
+++ b/src/compiler/translator/IntermNode.cpp
@@ -261,7 +261,7 @@ bool TIntermLoop::replaceChildNode(
    REPLACE_IF_IS(mInit, TIntermNode, original, replacement);
    REPLACE_IF_IS(mCond, TIntermTyped, original, replacement);
    REPLACE_IF_IS(mExpr, TIntermTyped, original, replacement);
-    REPLACE_IF_IS(mBody, TIntermNode, original, replacement);
+    REPLACE_IF_IS(mBody, TIntermAggregate, original, replacement);
    return false;
 }

--- a/src/compiler/translator/IntermNode.h
+++ b/src/compiler/translator/IntermNode.h
@@ -173,14 +173,13 @@ class TIntermLoop : public TIntermNode
 {
  public:
    TIntermLoop(TLoopType type,
-                TIntermNode *init, TIntermTyped *cond, TIntermTyped *expr,
+                TIntermNode *init,
-                TIntermNode *body)
+                TIntermTyped *cond,
-        : mType(type),
+                TIntermTyped *expr,
-          mInit(init),
+                TIntermAggregate *body)
-          mCond(cond),
+        : mType(type), mInit(init), mCond(cond), mExpr(expr), mBody(body), mUnrollFlag(false)
-          mExpr(expr),
+    {
-          mBody(body),
+    }
-          mUnrollFlag(false) { }
    TIntermLoop *getAsLoopNode() override { return this; }
    void traverse(TIntermTraverser *it) override;
@@ -190,7 +189,7 @@ class TIntermLoop : public TIntermNode
    TIntermNode *getInit() { return mInit; }
    TIntermTyped *getCondition() { return mCond; }
    TIntermTyped *getExpression() { return mExpr; }
-    TIntermNode *getBody() { return mBody; }
+    TIntermAggregate *getBody() { return mBody; }
    void setUnrollFlag(bool flag) { mUnrollFlag = flag; }
    bool getUnrollFlag() const { return mUnrollFlag; }
@@ -200,7 +199,7 @@ class TIntermLoop : public TIntermNode
    TIntermNode *mInit;  // for-loop initialization
    TIntermTyped *mCond; // loop exit condition
    TIntermTyped *mExpr; // for-loop expression
-    TIntermNode *mBody;  // loop body
+    TIntermAggregate *mBody;  // loop body
    bool mUnrollFlag; // Whether the loop should be unrolled or not.
 };

--- a/src/compiler/translator/UnfoldShortCircuitToIf.cpp
+++ b/src/compiler/translator/UnfoldShortCircuitToIf.cpp