Fix a fairly serious pessimizaion that was preventing us from efficiently
compiling things like 'add long %X, 1'. The problem is that we were switching
the order of the operands for longs even though we can't fold them yet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13451 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/InstSelectSimple.cpp b/lib/Target/X86/InstSelectSimple.cpp
index 3850388..8fbeeb7 100644
--- a/lib/Target/X86/InstSelectSimple.cpp
+++ b/lib/Target/X86/InstSelectSimple.cpp
@@ -1863,13 +1863,14 @@
unsigned DestReg = getReg(B);
MachineBasicBlock::iterator MI = BB->end();
Value *Op0 = B.getOperand(0), *Op1 = B.getOperand(1);
+ unsigned Class = getClassB(B.getType());
// Special case: op Reg, load [mem]
- if (isa<LoadInst>(Op0) && !isa<LoadInst>(Op1))
+ if (isa<LoadInst>(Op0) && !isa<LoadInst>(Op1) && Class != cLong &&
+ isSafeToFoldLoadIntoInstruction(*cast<LoadInst>(Op0), B))
if (!B.swapOperands())
std::swap(Op0, Op1); // Make sure any loads are in the RHS.
- unsigned Class = getClassB(B.getType());
if (isa<LoadInst>(Op1) && Class != cLong &&
isSafeToFoldLoadIntoInstruction(*cast<LoadInst>(Op1), B)) {
diff --git a/lib/Target/X86/X86ISelSimple.cpp b/lib/Target/X86/X86ISelSimple.cpp
index 3850388..8fbeeb7 100644
--- a/lib/Target/X86/X86ISelSimple.cpp
+++ b/lib/Target/X86/X86ISelSimple.cpp
@@ -1863,13 +1863,14 @@
unsigned DestReg = getReg(B);
MachineBasicBlock::iterator MI = BB->end();
Value *Op0 = B.getOperand(0), *Op1 = B.getOperand(1);
+ unsigned Class = getClassB(B.getType());
// Special case: op Reg, load [mem]
- if (isa<LoadInst>(Op0) && !isa<LoadInst>(Op1))
+ if (isa<LoadInst>(Op0) && !isa<LoadInst>(Op1) && Class != cLong &&
+ isSafeToFoldLoadIntoInstruction(*cast<LoadInst>(Op0), B))
if (!B.swapOperands())
std::swap(Op0, Op1); // Make sure any loads are in the RHS.
- unsigned Class = getClassB(B.getType());
if (isa<LoadInst>(Op1) && Class != cLong &&
isSafeToFoldLoadIntoInstruction(*cast<LoadInst>(Op1), B)) {