[llvm] r276712 - [safestack] Fix stack guard live range.

[Evgeniy Stepanov via llvm-commits]

Author: eugenis
Date: Mon Jul 25 19:05:14 2016
New Revision: 276712

URL: http://llvm.org/viewvc/llvm-project?rev=276712&view=rev
Log:
[safestack] Fix stack guard live range.

Stack guard slot is live throughout the function.

Added:
    llvm/trunk/test/Transforms/SafeStack/coloring-ssp.ll
Modified:
    llvm/trunk/lib/CodeGen/SafeStack.cpp
    llvm/trunk/lib/CodeGen/SafeStackColoring.cpp

Modified: llvm/trunk/lib/CodeGen/SafeStack.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SafeStack.cpp?rev=276712&r1=276711&r2=276712&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SafeStack.cpp (original)
+++ llvm/trunk/lib/CodeGen/SafeStack.cpp Mon Jul 25 19:05:14 2016
@@ -530,7 +530,7 @@ Value *SafeStack::moveStaticAllocasToUns
     unsigned Align =
         std::max(DL->getPrefTypeAlignment(Ty), StackGuardSlot->getAlignment());
     SSL.addObject(StackGuardSlot, getStaticAllocaAllocationSize(StackGuardSlot),
-                  Align, SSC.getLiveRange(StackGuardSlot));
+                  Align, SSC.getFullLiveRange());
   }
 
   for (Argument *Arg : ByValArguments) {

Modified: llvm/trunk/lib/CodeGen/SafeStackColoring.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SafeStackColoring.cpp?rev=276712&r1=276711&r2=276712&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SafeStackColoring.cpp (original)
+++ llvm/trunk/lib/CodeGen/SafeStackColoring.cpp Mon Jul 25 19:05:14 2016
@@ -25,7 +25,9 @@ static cl::opt<bool> ClColoring("safe-st
                                 cl::Hidden, cl::init(true));
 
 const StackColoring::LiveRange &StackColoring::getLiveRange(AllocaInst *AI) {
-  return LiveRanges[AllocaNumbering[AI]];
+  const auto IT = AllocaNumbering.find(AI);
+  assert(IT != AllocaNumbering.end());
+  return LiveRanges[IT->second];
 }
 
 bool StackColoring::readMarker(Instruction *I, bool *IsStart) {

Added: llvm/trunk/test/Transforms/SafeStack/coloring-ssp.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/coloring-ssp.ll?rev=276712&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/SafeStack/coloring-ssp.ll (added)
+++ llvm/trunk/test/Transforms/SafeStack/coloring-ssp.ll Mon Jul 25 19:05:14 2016
@@ -0,0 +1,34 @@
+; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
+
+; %x and %y share a stack slot between them, but not with the stack guard.
+define void @f() safestack sspreq {
+; CHECK-LABEL: define void @f
+entry:
+; CHECK:  %[[USP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
+; CHECK:   getelementptr i8, i8* %[[USP]], i32 -16
+
+; CHECK:  %[[A:.*]] = getelementptr i8, i8* %[[USP]], i32 -8
+; CHECK:  %[[StackGuardSlot:.*]] = bitcast i8* %[[A]] to i8**
+; CHECK:  store i8* %{{.*}}, i8** %[[StackGuardSlot]]
+
+  %x = alloca i64, align 8
+  %y = alloca i64, align 8
+  %x0 = bitcast i64* %x to i8*
+  %y0 = bitcast i64* %y to i8*
+
+  call void @llvm.lifetime.start(i64 -1, i8* %x0)
+; CHECK:  getelementptr i8, i8* %[[USP]], i32 -16
+  call void @capture64(i64* %x)
+  call void @llvm.lifetime.end(i64 -1, i8* %x0)
+
+  call void @llvm.lifetime.start(i64 -1, i8* %y0)
+; CHECK:  getelementptr i8, i8* %[[USP]], i32 -16
+  call void @capture64(i64* %y)
+  call void @llvm.lifetime.end(i64 -1, i8* %y0)
+
+  ret void
+}
+
+declare void @llvm.lifetime.start(i64, i8* nocapture)
+declare void @llvm.lifetime.end(i64, i8* nocapture)
+declare void @capture64(i64*)