Avoid allocating the same physreg to multiple virtregs in one instruction.
While that approach works wonders for register pressure, it tends to break
everything.
This should unbreak the arm-linux builder and fix a number of miscompilations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103946 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocFast.cpp b/lib/CodeGen/RegAllocFast.cpp
index ea3fa61..a8d1e0d 100644
--- a/lib/CodeGen/RegAllocFast.cpp
+++ b/lib/CodeGen/RegAllocFast.cpp
@@ -471,6 +471,7 @@
unsigned BestReg = 0, BestCost = spillImpossible;
for (TargetRegisterClass::iterator I = AOB; I != AOE; ++I) {
+ if (UsedInInstr.test(*I)) continue;
unsigned Cost = calcSpillCost(*I);
// Cost is 0 when all aliases are already disabled.
if (Cost == 0)