pr6480: Don't try producing ld/st-multiple instructions when the address is
an undef value. This is only going to come up for bugpoint-reduced tests --
correct programs will not access memory at undefined addresses -- so it's not
worth the effort of doing anything more aggressive.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97745 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
index 5b4f02d..19f1e3b 100644
--- a/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
+++ b/lib/Target/ARM/ARMLoadStoreOptimizer.cpp
@@ -761,6 +761,11 @@
MI->getOperand(0).isUndef())
return false;
+ // Likewise don't mess with references to undefined addresses.
+ if (MI->getNumOperands() > 1 && MI->getOperand(1).isReg() &&
+ MI->getOperand(1).isUndef())
+ return false;
+
int Opcode = MI->getOpcode();
switch (Opcode) {
default: break;