[llvm] r231539 - Recommit r231324 with a fix to the ARM execution domain code

[Eric Christopher]

Author: echristo
Date: Fri Mar  6 18:12:22 2015
New Revision: 231539

URL: http://llvm.org/viewvc/llvm-project?rev=231539&view=rev
Log:
Recommit r231324 with a fix to the ARM execution domain code
to disable lane switching if we don't actually have the instruction
set we want to switch to. Models the earlier check above the
conditional for the pass.

The testcase is one that triggered with the assert that's added
as part of the fix, use it to avoid adding a new testcase as it
highlights the same problem.

Modified:
    llvm/trunk/lib/Target/ARM/ARMBaseInstrInfo.cpp
    llvm/trunk/lib/Target/ARM/ARMTargetMachine.cpp
    llvm/trunk/test/CodeGen/ARM/2007-01-19-InfiniteLoop.ll

Modified: llvm/trunk/lib/Target/ARM/ARMBaseInstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMBaseInstrInfo.cpp?rev=231539&r1=231538&r2=231539&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMBaseInstrInfo.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMBaseInstrInfo.cpp Fri Mar  6 18:12:22 2015
@@ -4115,19 +4115,21 @@ enum ARMExeDomain {
 //
 std::pair<uint16_t, uint16_t>
 ARMBaseInstrInfo::getExecutionDomain(const MachineInstr *MI) const {
-  // VMOVD, VMOVRS and VMOVSR are VFP instructions, but can be changed to NEON
-  // if they are not predicated.
-  if (MI->getOpcode() == ARM::VMOVD && !isPredicated(MI))
-    return std::make_pair(ExeVFP, (1<<ExeVFP) | (1<<ExeNEON));
-
-  // CortexA9 is particularly picky about mixing the two and wants these
-  // converted.
-  if (Subtarget.isCortexA9() && !isPredicated(MI) &&
-      (MI->getOpcode() == ARM::VMOVRS ||
-       MI->getOpcode() == ARM::VMOVSR ||
-       MI->getOpcode() == ARM::VMOVS))
-    return std::make_pair(ExeVFP, (1<<ExeVFP) | (1<<ExeNEON));
-
+  // If we don't have access to NEON instructions then we won't be able
+  // to swizzle anything to the NEON domain. Check to make sure.
+  if (Subtarget.hasNEON()) {
+    // VMOVD, VMOVRS and VMOVSR are VFP instructions, but can be changed to NEON
+    // if they are not predicated.
+    if (MI->getOpcode() == ARM::VMOVD && !isPredicated(MI))
+      return std::make_pair(ExeVFP, (1 << ExeVFP) | (1 << ExeNEON));
+
+    // CortexA9 is particularly picky about mixing the two and wants these
+    // converted.
+    if (Subtarget.isCortexA9() && !isPredicated(MI) &&
+        (MI->getOpcode() == ARM::VMOVRS || MI->getOpcode() == ARM::VMOVSR ||
+         MI->getOpcode() == ARM::VMOVS))
+      return std::make_pair(ExeVFP, (1 << ExeVFP) | (1 << ExeNEON));
+  }
   // No other instructions can be swizzled, so just determine their domain.
   unsigned Domain = MI->getDesc().TSFlags & ARMII::DomainMask;
 
@@ -4220,6 +4222,9 @@ ARMBaseInstrInfo::setExecutionDomain(Mac
       // Zap the predicate operands.
       assert(!isPredicated(MI) && "Cannot predicate a VORRd");
 
+      // Make sure we've got NEON instructions.
+      assert(Subtarget.hasNEON() && "VORRd requires NEON");
+
       // Source instruction is %DDst = VMOVD %DSrc, 14, %noreg (; implicits)
       DstReg = MI->getOperand(0).getReg();
       SrcReg = MI->getOperand(1).getReg();

Modified: llvm/trunk/lib/Target/ARM/ARMTargetMachine.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMTargetMachine.cpp?rev=231539&r1=231538&r2=231539&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMTargetMachine.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMTargetMachine.cpp Fri Mar  6 18:12:22 2015
@@ -358,9 +358,7 @@ void ARMPassConfig::addPreRegAlloc() {
 void ARMPassConfig::addPreSched2() {
   if (getOptLevel() != CodeGenOpt::None) {
     addPass(createARMLoadStoreOptimizationPass());
-
-    if (getARMSubtarget().hasNEON())
-      addPass(createExecutionDependencyFixPass(&ARM::DPRRegClass));
+    addPass(createExecutionDependencyFixPass(&ARM::DPRRegClass));
   }
 
   // Expand some pseudo instructions into multiple instructions to allow

Modified: llvm/trunk/test/CodeGen/ARM/2007-01-19-InfiniteLoop.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM/2007-01-19-InfiniteLoop.ll?rev=231539&r1=231538&r2=231539&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/ARM/2007-01-19-InfiniteLoop.ll (original)
+++ llvm/trunk/test/CodeGen/ARM/2007-01-19-InfiniteLoop.ll Fri Mar  6 18:12:22 2015
@@ -1,5 +1,9 @@
 ; RUN: llc < %s -mtriple=arm-apple-ios -mattr=+v6,+vfp2 | FileCheck %s
+; RUN: llc < %s -mtriple=arm-apple-ios -mattr=+v6,+vfp2 | FileCheck --check-prefix=DOMAIN %s
 
+; The execution domain checking code would translate vmovs to vorr whether or not
+; we had NEON instructions. Verify we don't if we're not compiled with NEON.
+; DOMAIN-NOT: vorr
 @quant_coef = external global [6 x [4 x [4 x i32]]]		; <[6 x [4 x [4 x i32]]]*> [#uses=1]
 @dequant_coef = external global [6 x [4 x [4 x i32]]]		; <[6 x [4 x [4 x i32]]]*> [#uses=1]
 @A = external global [4 x [4 x i32]]		; <[4 x [4 x i32]]*> [#uses=1]