Do not model all INLINEASM instructions as having unmodelled side effects.
Instead encode llvm IR level property "HasSideEffects" in an operand (shared
with IsAlignStack). Added MachineInstrs::hasUnmodeledSideEffects() to check
the operand when the instruction is an INLINEASM.
This allows memory instructions to be moved around INLINEASM instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123044 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/VirtRegRewriter.cpp b/lib/CodeGen/VirtRegRewriter.cpp
index d04b928..8778106 100644
--- a/lib/CodeGen/VirtRegRewriter.cpp
+++ b/lib/CodeGen/VirtRegRewriter.cpp
@@ -1620,9 +1620,16 @@
const TargetInstrDesc &TID = MI.getDesc();
if (TID.mayLoad() || TID.mayStore() || TID.isCall() || TID.isTerminator() ||
TID.isCall() || TID.isBarrier() || TID.isReturn() ||
- TID.hasUnmodeledSideEffects() ||
- MI.isLabel() || MI.isDebugValue())
+ MI.isLabel() || MI.isDebugValue() ||
+ MI.hasUnmodeledSideEffects())
return false;
+
+ // Technically speaking inline asm without side effects and no defs can still
+ // be deleted. But there is so much bad inline asm code out there, we should
+ // let them be.
+ if (MI.isInlineAsm())
+ return false;
+
for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) {
MachineOperand &MO = MI.getOperand(i);
if (!MO.isReg() || !MO.getReg())