fix a regression handling indirect results: these need to be considered
memory operands otherwise the writebacks get lost when the inline asm
doesn't otherwise have side effects. This fixes rdar://6839427, though
clang really shouldn't generate these anymore.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70455 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
index 01d73b3..71f5d81 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
@@ -5075,6 +5075,10 @@
if (CType == TargetLowering::C_Memory)
return true;
}
+
+ // Indirect operand accesses access memory.
+ if (CI.isIndirect)
+ return true;
}
return false;
@@ -5088,11 +5092,6 @@
/// ConstraintOperands - Information about all of the constraints.
std::vector<SDISelAsmOperandInfo> ConstraintOperands;
- // We won't need to flush pending loads if this asm doesn't touch
- // memory and is nonvolatile.
- SDValue Chain = IA->hasSideEffects() ? getRoot() : DAG.getRoot();
- SDValue Flag;
-
std::set<unsigned> OutputRegs, InputRegs;
// Do a prepass over the constraints, canonicalizing them, and building up the
@@ -5101,10 +5100,15 @@
ConstraintInfos = IA->ParseConstraints();
bool hasMemory = hasInlineAsmMemConstraint(ConstraintInfos, TLI);
- // Flush pending loads if this touches memory (includes clobbering it).
- // It's possible this is overly conservative.
- if (hasMemory)
+
+ SDValue Chain, Flag;
+
+ // We won't need to flush pending loads if this asm doesn't touch
+ // memory and is nonvolatile.
+ if (hasMemory || IA->hasSideEffects())
Chain = getRoot();
+ else
+ Chain = DAG.getRoot();
unsigned ArgNo = 0; // ArgNo - The argument of the CallInst.
unsigned ResNo = 0; // ResNo - The result number of the next output.
@@ -5482,6 +5486,7 @@
SDValue OutVal = OutRegs.getCopyFromRegs(DAG, getCurDebugLoc(),
Chain, &Flag);
StoresToEmit.push_back(std::make_pair(OutVal, Ptr));
+
}
// Emit the non-flagged stores from the physregs.