[llvm-commits] [llvm] r100837 - in /llvm/trunk: lib/Transforms/Scalar/SCCP.cpp test/Transforms/SCCP/undef-resolve.ll
Chris Lattner
sabre at nondot.org
Thu Apr 8 18:14:31 PDT 2010
Author: lattner
Date: Thu Apr 8 20:14:31 2010
New Revision: 100837
URL: http://llvm.org/viewvc/llvm-project?rev=100837&view=rev
Log:
fix a SCCP miscompilation that could happen when a
forced constant is changed to a constant, we would end
up adding the instruction to the wrong worklist,
preventing it from being properly revisited. This fixes
rdar://7832370
Added:
llvm/trunk/test/Transforms/SCCP/undef-resolve.ll
Modified:
llvm/trunk/lib/Transforms/Scalar/SCCP.cpp
Modified: llvm/trunk/lib/Transforms/Scalar/SCCP.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/SCCP.cpp?rev=100837&r1=100836&r2=100837&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/SCCP.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/SCCP.cpp Thu Apr 8 20:14:31 2010
@@ -317,7 +317,10 @@
void markConstant(LatticeVal &IV, Value *V, Constant *C) {
if (!IV.markConstant(C)) return;
DEBUG(dbgs() << "markConstant: " << *C << ": " << *V << '\n');
- InstWorkList.push_back(V);
+ if (IV.isOverdefined())
+ OverdefinedInstWorkList.push_back(V);
+ else
+ InstWorkList.push_back(V);
}
void markConstant(Value *V, Constant *C) {
@@ -327,9 +330,13 @@
void markForcedConstant(Value *V, Constant *C) {
assert(!V->getType()->isStructTy() && "Should use other method");
- ValueState[V].markForcedConstant(C);
+ LatticeVal &IV = ValueState[V];
+ IV.markForcedConstant(C);
DEBUG(dbgs() << "markForcedConstant: " << *C << ": " << *V << '\n');
- InstWorkList.push_back(V);
+ if (IV.isOverdefined())
+ OverdefinedInstWorkList.push_back(V);
+ else
+ InstWorkList.push_back(V);
}
Added: llvm/trunk/test/Transforms/SCCP/undef-resolve.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SCCP/undef-resolve.ll?rev=100837&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/SCCP/undef-resolve.ll (added)
+++ llvm/trunk/test/Transforms/SCCP/undef-resolve.ll Thu Apr 8 20:14:31 2010
@@ -0,0 +1,95 @@
+; RUN: opt %s -sccp -S | FileCheck %s
+; rdar://7832370
+; Check that lots of stuff doesn't get turned into undef.
+
+define i32 @main() nounwind readnone ssp {
+init:
+ br label %control.outer.outer
+
+control.outer.loopexit.us-lcssa: ; preds = %control
+ br label %control.outer.loopexit
+
+control.outer.loopexit: ; preds = %control.outer.loopexit.us-lcssa.us, %control.outer.loopexit.us-lcssa
+ br label %control.outer.outer.backedge
+
+control.outer.outer: ; preds = %control.outer.outer.backedge, %init
+ %switchCond.0.ph.ph = phi i32 [ 2, %init ], [ 3, %control.outer.outer.backedge ] ; <i32> [#uses=2]
+ %i.0.ph.ph = phi i32 [ undef, %init ], [ %i.0.ph.ph.be, %control.outer.outer.backedge ] ; <i32> [#uses=1]
+ %tmp4 = icmp eq i32 %i.0.ph.ph, 0 ; <i1> [#uses=1]
+ br i1 %tmp4, label %control.outer.outer.split.us, label %control.outer.outer.control.outer.outer.split_crit_edge
+
+control.outer.outer.control.outer.outer.split_crit_edge: ; preds = %control.outer.outer
+ br label %control.outer
+
+control.outer.outer.split.us: ; preds = %control.outer.outer
+ br label %control.outer.us
+
+control.outer.us: ; preds = %bb3.us, %control.outer.outer.split.us
+ %A.0.ph.us = phi i32 [ %switchCond.0.us, %bb3.us ], [ 4, %control.outer.outer.split.us ] ; <i32> [#uses=2]
+ %switchCond.0.ph.us = phi i32 [ %A.0.ph.us, %bb3.us ], [ %switchCond.0.ph.ph, %control.outer.outer.split.us ] ; <i32> [#uses=1]
+ br label %control.us
+
+bb3.us: ; preds = %control.us
+ br label %control.outer.us
+
+bb0.us: ; preds = %control.us
+ br label %control.us
+
+; CHECK: control.us: ; preds = %bb0.us, %control.outer.us
+; CHECK-NEXT: %switchCond.0.us = phi i32
+; CHECK-NEXT: switch i32 %switchCond.0.us
+control.us: ; preds = %bb0.us, %control.outer.us
+ %switchCond.0.us = phi i32 [ %A.0.ph.us, %bb0.us ], [ %switchCond.0.ph.us, %control.outer.us ] ; <i32> [#uses=2]
+ switch i32 %switchCond.0.us, label %control.outer.loopexit.us-lcssa.us [
+ i32 0, label %bb0.us
+ i32 1, label %bb1.us-lcssa.us
+ i32 3, label %bb3.us
+ i32 4, label %bb4.us-lcssa.us
+ ]
+
+control.outer.loopexit.us-lcssa.us: ; preds = %control.us
+ br label %control.outer.loopexit
+
+bb1.us-lcssa.us: ; preds = %control.us
+ br label %bb1
+
+bb4.us-lcssa.us: ; preds = %control.us
+ br label %bb4
+
+control.outer: ; preds = %bb3, %control.outer.outer.control.outer.outer.split_crit_edge
+ %A.0.ph = phi i32 [ %nextId17, %bb3 ], [ 4, %control.outer.outer.control.outer.outer.split_crit_edge ] ; <i32> [#uses=1]
+ %switchCond.0.ph = phi i32 [ 0, %bb3 ], [ %switchCond.0.ph.ph, %control.outer.outer.control.outer.outer.split_crit_edge ] ; <i32> [#uses=1]
+ br label %control
+
+control: ; preds = %bb0, %control.outer
+ %switchCond.0 = phi i32 [ %A.0.ph, %bb0 ], [ %switchCond.0.ph, %control.outer ] ; <i32> [#uses=2]
+ switch i32 %switchCond.0, label %control.outer.loopexit.us-lcssa [
+ i32 0, label %bb0
+ i32 1, label %bb1.us-lcssa
+ i32 3, label %bb3
+ i32 4, label %bb4.us-lcssa
+ ]
+
+bb4.us-lcssa: ; preds = %control
+ br label %bb4
+
+bb4: ; preds = %bb4.us-lcssa, %bb4.us-lcssa.us
+ br label %control.outer.outer.backedge
+
+control.outer.outer.backedge: ; preds = %bb4, %control.outer.loopexit
+ %i.0.ph.ph.be = phi i32 [ 1, %bb4 ], [ 0, %control.outer.loopexit ] ; <i32> [#uses=1]
+ br label %control.outer.outer
+
+bb3: ; preds = %control
+ %nextId17 = add i32 %switchCond.0, -2 ; <i32> [#uses=1]
+ br label %control.outer
+
+bb0: ; preds = %control
+ br label %control
+
+bb1.us-lcssa: ; preds = %control
+ br label %bb1
+
+bb1: ; preds = %bb1.us-lcssa, %bb1.us-lcssa.us
+ ret i32 0
+}
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