Pull in r316035 from upstream llvm trunk (by Tim Northover):

  AArch64: account for possible frame index operand in compares.

  If the address of a local is used in a comparison, AArch64 can fold
  the address-calculation into the comparison via "adds".
  Unfortunately, a couple of places (both hit in this one test) are not
  ready to deal with that yet and just assume the first source operand
  is a register.

This should fix an assertion failure while building the test suite of
www/firefox for AArch64.

PR:		223048
MFC after:	3 days

2 files changed, 9 insertions, 0 deletions

diff --git a/contrib/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp b/contrib/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
index c0c6055c358f..13c80a46e5b0 100644
--- a/contrib/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
+++ b/contrib/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
@@ -940,6 +940,12 @@ bool AArch64InstrInfo::areMemAccessesTriviallyDisjoint(
 bool AArch64InstrInfo::analyzeCompare(const MachineInstr &MI, unsigned &SrcReg,
                                       unsigned &SrcReg2, int &CmpMask,
                                       int &CmpValue) const {
+  // The first operand can be a frame index where we'd normally expect a
+  // register.
+  assert(MI.getNumOperands() >= 2 && "All AArch64 cmps should have 2 operands");
+  if (!MI.getOperand(1).isReg())
+    return false;
+
   switch (MI.getOpcode()) {
   default:
     break;
diff --git a/contrib/llvm/lib/Target/AArch64/AArch64RedundantCopyElimination.cpp b/contrib/llvm/lib/Target/AArch64/AArch64RedundantCopyElimination.cpp
index 4e65c0ab6011..22c11c7276d2 100644
--- a/contrib/llvm/lib/Target/AArch64/AArch64RedundantCopyElimination.cpp
+++ b/contrib/llvm/lib/Target/AArch64/AArch64RedundantCopyElimination.cpp
@@ -167,6 +167,9 @@ AArch64RedundantCopyElimination::knownRegValInBlock(
     // CMP is an alias for SUBS with a dead destination register.
     case AArch64::SUBSWri:
     case AArch64::SUBSXri: {
+      // Sometimes the first operand is a FrameIndex. Bail if tht happens.
+      if (!PredI.getOperand(1).isReg())
+        return None;
       MCPhysReg SrcReg = PredI.getOperand(1).getReg();
 
       // Must not be a symbolic immediate.