PNaCl ABI checker: Disallow llvm.lifetime.start/end intrinsics

Run StripDeadPrototypes as a final pass to ensure that the prototypes
for lifetime.start/end are removed.

BUG=https://code.google.com/p/nativeclient/issues/detail?id=3443
TEST=PNaCl toolchain trybots

Review URL: https://codereview.chromium.org/16063005

3 files changed, 18 insertions, 12 deletions

diff --git a/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp b/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
index 0e406e6512..9b2def5ac4 100644
--- a/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
+++ b/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
@@ -163,8 +163,6 @@ bool PNaClABIVerifyModule::isWhitelistedIntrinsic(const Function *F,
     case Intrinsic::bswap: return isWhitelistedBswap(F);
     case Intrinsic::invariant_end:
     case Intrinsic::invariant_start:
-    case Intrinsic::lifetime_end:
-    case Intrinsic::lifetime_start:
     case Intrinsic::memcpy:
     case Intrinsic::memmove:
     case Intrinsic::memset:
@@ -210,6 +208,13 @@ bool PNaClABIVerifyModule::isWhitelistedIntrinsic(const Function *F,
     case Intrinsic::usub_with_overflow:
     case Intrinsic::smul_with_overflow:
     case Intrinsic::umul_with_overflow:
+    // Disallow lifetime.start/end because the semantics of what
+    // arguments they accept are not very well defined, and because it
+    // would be better to do merging of stack slots in the user
+    // toolchain than in the PNaCl translator.
+    // See https://code.google.com/p/nativeclient/issues/detail?id=3443
+    case Intrinsic::lifetime_end:
+    case Intrinsic::lifetime_start:
       return false;
 
     // (3) Dev intrinsics.
diff --git a/lib/Transforms/NaCl/PNaClABISimplify.cpp b/lib/Transforms/NaCl/PNaClABISimplify.cpp
index 8c945800af..74a9f0730e 100644
--- a/lib/Transforms/NaCl/PNaClABISimplify.cpp
+++ b/lib/Transforms/NaCl/PNaClABISimplify.cpp
@@ -39,9 +39,6 @@ void llvm::PNaClABISimplifyAddPreOptPasses(PassManager &PM) {
   // GlobalCleanup needs to run after ExpandTls because
   // __tls_template_start etc. are extern_weak before expansion
   PM.add(createGlobalCleanupPass());
-  // Strip dead prototytes to appease the intrinsic ABI checks
-  // (ExpandVarArgs leaves around var-arg intrinsics).
-  PM.add(createStripDeadPrototypesPass());
 }
 
 void llvm::PNaClABISimplifyAddPostOptPasses(PassManager &PM) {
@@ -78,4 +75,9 @@ void llvm::PNaClABISimplifyAddPostOptPasses(PassManager &PM) {
   // ReplacePtrsWithInts assumes that getelementptr instructions and
   // ConstantExprs have already been expanded out.
   PM.add(createReplacePtrsWithIntsPass());
+
+  // Strip dead prototytes to appease the intrinsic ABI checks.
+  // ExpandVarArgs leaves around vararg intrinsics, and
+  // ReplacePtrsWithInts leaves the lifetime.start/end intrinsics.
+  PM.add(createStripDeadPrototypesPass());
 }
diff --git a/test/NaCl/PNaClABI/intrinsics.ll b/test/NaCl/PNaClABI/intrinsics.ll
index d54a9fe863..e5fe6116ed 100644
--- a/test/NaCl/PNaClABI/intrinsics.ll
+++ b/test/NaCl/PNaClABI/intrinsics.ll
@@ -21,13 +21,6 @@ declare i8* @llvm.returnaddress(i32 %level)
 
 ; ===================================
 ; Always allowed intrinsics.
-; CHECK-NOT: Function llvm.lifetime.start is a disallowed LLVM intrinsic
-; DBG-NOT: Function llvm.lifetime.start is a disallowed LLVM intrinsic
-; DEV-NOT: Function llvm.lifetime.start is a disallowed LLVM intrinsic
-declare void @llvm.lifetime.start(i64, i8* nocapture)
-
-; CHECK-NOT: Function llvm.lifetime.start is a disallowed LLVM intrinsic
-declare void @llvm.lifetime.end(i64, i8* nocapture)
 
 ; CHECK-NOT: Function llvm.memcpy.p0i8.p0i8.i32 is a disallowed LLVM intrinsic
 declare void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src,
@@ -75,3 +68,9 @@ declare i1 @llvm.bswap.1(i1)
 
 ; CHECK: Function llvm.bswap.8 is a disallowed LLVM intrinsic
 declare i8 @llvm.bswap.8(i8)
+
+; CHECK: Function llvm.lifetime.start is a disallowed LLVM intrinsic
+declare void @llvm.lifetime.start(i64, i8* nocapture)
+
+; CHECK: Function llvm.lifetime.end is a disallowed LLVM intrinsic
+declare void @llvm.lifetime.end(i64, i8* nocapture)