[optnone] Skip pass Constant Hoisting on optnone functions.

Added test CodeGen/X86/constant-hoisting-optnone.ll to verify that
pass Constant Hoisting is not run on optnone functions.

llvm-svn: 229258

2 files changed, 24 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp b/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp
index b84fe37e6c8..e3aab4b40a0 100644
--- a/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp
+++ b/llvm/lib/Transforms/Scalar/ConstantHoisting.cpp
@@ -186,6 +186,9 @@ FunctionPass *llvm::createConstantHoistingPass() {
 
 /// \brief Perform the constant hoisting optimization for the given function.
 bool ConstantHoisting::runOnFunction(Function &Fn) {
+  if (skipOptnoneFunction(Fn))
+    return false;
+
   DEBUG(dbgs() << "********** Begin Constant Hoisting **********\n");
   DEBUG(dbgs() << "********** Function: " << Fn.getName() << '\n');
 
diff --git a/llvm/test/CodeGen/X86/constant-hoisting-optnone.ll b/llvm/test/CodeGen/X86/constant-hoisting-optnone.ll
new file mode 100644
index 00000000000..f61fe3f60f9
--- /dev/null
+++ b/llvm/test/CodeGen/X86/constant-hoisting-optnone.ll
@@ -0,0 +1,21 @@
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=generic | FileCheck %s
+;
+; Verify that pass 'Constant Hoisting' is not run on optnone functions.
+; Without optnone, Pass 'Constant Hoisting' would firstly hoist
+; constant 0xBEEBEEBEC, and then rebase the other constant
+; (i.e. constant 0xBEEBEEBF4) with respect to the previous one.
+; With optnone, we check that constants are not coalesced.
+
+define i64 @constant_hoisting_optnone() #0 {
+; CHECK-LABEL: @constant_hoisting_optnone
+; CHECK-DAG: movabsq {{.*#+}} imm = 0xBEEBEEBF4
+; CHECK-DAG: movabsq {{.*#+}} imm = 0xBEEBEEBEC
+; CHECK: ret
+entry:
+  %0 = load i64* inttoptr (i64 51250129900 to i64*)
+  %1 = load i64* inttoptr (i64 51250129908 to i64*)
+  %2 = add i64 %0, %1
+  ret i64 %2
+}
+
+attributes #0 = { optnone noinline }