Fix the recently added anyregcc convention to handle spilled operands.

Fixes <rdar://15432754> [JS] Assertion: "Folded a def to a non-store!"

The primary purpose of anyregcc is to prevent a patchpoint's call
arguments and return value from being spilled. They must be available
in a register, although the calling convention does not pin the
register. It's up to the front end to avoid using this convention for
calls with more arguments than allocatable registers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194428 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 1 deletions

diff --git a/lib/Target/X86/X86InstrInfo.cpp b/lib/Target/X86/X86InstrInfo.cpp
index b81b244..eda285b 100644
--- a/lib/Target/X86/X86InstrInfo.cpp
+++ b/lib/Target/X86/X86InstrInfo.cpp
@@ -4207,10 +4207,19 @@ static MachineInstr* foldPatchpoint(MachineFunction &MF,
   MachineInstrBuilder MIB(MF, NewMI);
 
   bool isPatchPoint = MI->getOpcode() == TargetOpcode::PATCHPOINT;
+  // For PatchPoint, the call args are not foldable.
+  unsigned NumCallArgs = MI->getOperand(StartIdx+3).getImm();
   StartIdx = isPatchPoint ?
-             StartIdx + MI->getOperand(StartIdx+3).getImm() + 5 :
+             StartIdx + NumCallArgs + 5 :
              StartIdx + 2;
 
+  // Return false if any operands requested for folding are not foldable (not
+  // part of the stackmap's live values).
+  for (SmallVectorImpl<unsigned>::const_iterator I = Ops.begin(), E = Ops.end();
+       I != E; ++I) {
+    if (*I < StartIdx)
+      return 0;
+  }
   // No need to fold return, the meta data, and function arguments
   for (unsigned i = 0; i < StartIdx; ++i)
     MIB.addOperand(MI->getOperand(i));