[llvm] r328674 - [MachineOutliner] AArch64: Don't outline ADRPs with un-outlinable operands

[Jessica Paquette via llvm-commits]

Author: paquette
Date: Tue Mar 27 15:23:48 2018
New Revision: 328674

URL: http://llvm.org/viewvc/llvm-project?rev=328674&view=rev
Log:
[MachineOutliner] AArch64: Don't outline ADRPs with un-outlinable operands

If an ADRP appears with, say, a CPI operand, we shouldn't outline it.

This moves the check for unsafe operands so that it occurs before the special-case
for ADRPs. Also add a test for outlining ADRPs.


Added:
    llvm/trunk/test/CodeGen/AArch64/machine-outliner-bad-adrp.mir
Modified:
    llvm/trunk/lib/Target/AArch64/AArch64InstrInfo.cpp

Modified: llvm/trunk/lib/Target/AArch64/AArch64InstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AArch64/AArch64InstrInfo.cpp?rev=328674&r1=328673&r2=328674&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AArch64/AArch64InstrInfo.cpp (original)
+++ llvm/trunk/lib/Target/AArch64/AArch64InstrInfo.cpp Tue Mar 27 15:23:48 2018
@@ -5053,6 +5053,13 @@ AArch64InstrInfo::getOutliningType(Machi
     return MachineOutlinerInstrType::Illegal;
   }
 
+  // Make sure none of the operands are un-outlinable.
+  for (const MachineOperand &MOP : MI.operands()) {
+    if (MOP.isCPI() || MOP.isJTI() || MOP.isCFIIndex() || MOP.isFI() ||
+        MOP.isTargetIndex())
+      return MachineOutlinerInstrType::Illegal;
+  }
+
   // Special cases for instructions that can always be outlined, but will fail
   // the later tests. e.g, ADRPs, which are PC-relative use LR, but can always
   // be outlined because they don't require a *specific* value to be in LR.
@@ -5132,17 +5139,6 @@ AArch64InstrInfo::getOutliningType(Machi
       MI.modifiesRegister(AArch64::W30, &getRegisterInfo()))
     return MachineOutlinerInstrType::Illegal;
 
-  // Make sure none of the operands are un-outlinable.
-  for (const MachineOperand &MOP : MI.operands()) {
-    if (MOP.isCPI() || MOP.isJTI() || MOP.isCFIIndex() || MOP.isFI() ||
-        MOP.isTargetIndex())
-      return MachineOutlinerInstrType::Illegal;
-
-    // Don't outline anything that uses the link register.
-    if (MOP.isReg() && getRegisterInfo().regsOverlap(MOP.getReg(), AArch64::LR))
-      return MachineOutlinerInstrType::Illegal;
-  }
-
   // Does this use the stack?
   if (MI.modifiesRegister(AArch64::SP, &RI) ||
       MI.readsRegister(AArch64::SP, &RI)) {

Added: llvm/trunk/test/CodeGen/AArch64/machine-outliner-bad-adrp.mir
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AArch64/machine-outliner-bad-adrp.mir?rev=328674&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/AArch64/machine-outliner-bad-adrp.mir (added)
+++ llvm/trunk/test/CodeGen/AArch64/machine-outliner-bad-adrp.mir Tue Mar 27 15:23:48 2018
@@ -0,0 +1,41 @@
+
+# RUN: llc -mtriple=aarch64--- -verify-machineinstrs -simplify-mir -run-pass=machine-outliner %s -o - | FileCheck %s
+--- |
+
+  define void @foo() #0 {
+    ret void
+  }
+
+  attributes #0 = { noredzone }
+...
+---
+name:            foo
+constants:       
+  - id:              0
+    value:           'float 1.990000e+02'
+    alignment:       4
+    isTargetSpecific: false
+body:             |
+    bb.0:
+    liveins: $w1, $w10, $x14, $x15, $x16, $x10, $lr
+    ; CHECK-NOT: BL
+
+    $w10 = MOVZWi 4, 0, implicit-def $x10
+
+    renamable $x14 = ADRP target-flags(aarch64-page) %const.0
+    renamable $x15 = ADRP target-flags(aarch64-page) %const.0
+    renamable $x16 = ADRP target-flags(aarch64-page) %const.0
+
+    $w10 = MOVZWi 5, 0, implicit-def $x10
+
+    renamable $x14 = ADRP target-flags(aarch64-page) %const.0
+    renamable $x15 = ADRP target-flags(aarch64-page) %const.0
+    renamable $x16 = ADRP target-flags(aarch64-page) %const.0
+
+    $w10 = MOVZWi 6, 0, implicit-def $x10
+
+    renamable $x14 = ADRP target-flags(aarch64-page) %const.0
+    renamable $x15 = ADRP target-flags(aarch64-page) %const.0
+    renamable $x16 = ADRP target-flags(aarch64-page) %const.0
+
+    RET undef $lr