svn commit: r324826 - head/contrib/llvm/lib/Target/AArch64

[Dimitry Andric]

Author: dim
Date: Sat Oct 21 19:14:45 2017
New Revision: 324826
URL: https://svnweb.freebsd.org/changeset/base/324826

Log:
  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

Modified:
  head/contrib/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
  head/contrib/llvm/lib/Target/AArch64/AArch64RedundantCopyElimination.cpp

Modified: head/contrib/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp
==============================================================================
--- head/contrib/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp	Sat Oct 21 18:21:44 2017	(r324825)
+++ head/contrib/llvm/lib/Target/AArch64/AArch64InstrInfo.cpp	Sat Oct 21 19:14:45 2017	(r324826)
@@ -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;

Modified: head/contrib/llvm/lib/Target/AArch64/AArch64RedundantCopyElimination.cpp
==============================================================================
--- head/contrib/llvm/lib/Target/AArch64/AArch64RedundantCopyElimination.cpp	Sat Oct 21 18:21:44 2017	(r324825)
+++ head/contrib/llvm/lib/Target/AArch64/AArch64RedundantCopyElimination.cpp	Sat Oct 21 19:14:45 2017	(r324826)
@@ -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.