[llvm-commits] [llvm] r119182 - in /llvm/trunk: lib/CodeGen/InlineSpiller.cpp test/CodeGen/ARM/2010-11-15-SpillEarlyClobber.ll

[Jakob Stoklund Olesen]

Author: stoklund
Date: Mon Nov 15 14:55:49 2010
New Revision: 119182

URL: http://llvm.org/viewvc/llvm-project?rev=119182&view=rev
Log:
When spilling a register defined by an early clobber, make sure that the new
live ranges for the spill register are also defined at the use slot instead of
the normal def slot.

This fixes PR8612 for the inline spiller. A use was being allocated to the same
register as a spilled early clobber def.

This problem exists in all the spillers. A fix for the standard spiller is
forthcoming.

Added:
    llvm/trunk/test/CodeGen/ARM/2010-11-15-SpillEarlyClobber.ll
Modified:
    llvm/trunk/lib/CodeGen/InlineSpiller.cpp

Modified: llvm/trunk/lib/CodeGen/InlineSpiller.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/InlineSpiller.cpp?rev=119182&r1=119181&r2=119182&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/InlineSpiller.cpp (original)
+++ llvm/trunk/lib/CodeGen/InlineSpiller.cpp Mon Nov 15 14:55:49 2010
@@ -343,7 +343,13 @@
 void InlineSpiller::insertSpill(LiveInterval &NewLI,
                                 MachineBasicBlock::iterator MI) {
   MachineBasicBlock &MBB = *MI->getParent();
+
+  // Get the defined value. It could be an early clobber so keep the def index.
   SlotIndex Idx = lis_.getInstructionIndex(MI).getDefIndex();
+  VNInfo *VNI = edit_->getParent().getVNInfoAt(Idx);
+  assert(VNI && VNI->def.getDefIndex() == Idx && "Inconsistent VNInfo");
+  Idx = VNI->def;
+
   tii_.storeRegToStackSlot(MBB, ++MI, NewLI.reg, true, stackSlot_, rc_, &tri_);
   --MI; // Point to store instruction.
   SlotIndex StoreIdx = lis_.InsertMachineInstrInMaps(MI).getDefIndex();

Added: llvm/trunk/test/CodeGen/ARM/2010-11-15-SpillEarlyClobber.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/ARM/2010-11-15-SpillEarlyClobber.ll?rev=119182&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/ARM/2010-11-15-SpillEarlyClobber.ll (added)
+++ llvm/trunk/test/CodeGen/ARM/2010-11-15-SpillEarlyClobber.ll Mon Nov 15 14:55:49 2010
@@ -0,0 +1,84 @@
+; RUN: llc < %s -verify-machineinstrs -spiller=inline
+; PR8612
+;
+; This test has an inline asm with early-clobber arguments.
+; It is big enough that one of the early clobber registers is spilled.
+;
+; All the spillers would get the live ranges wrong when spilling an early
+; clobber, allowing the undef register to be allocated to the same register as
+; the early clobber.
+;
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:64:128-a0:0:64-n32"
+target triple = "armv7-eabi"
+
+%0 = type { i32, i32 }
+
+define void @foo(i32* %in) nounwind {
+entry:
+  br label %bb.i
+
+bb.i:                                             ; preds = %bb.i, %entry
+  br i1 undef, label %bb10.preheader.i, label %bb.i
+
+bb10.preheader.i:                                 ; preds = %bb.i
+  br label %bb10.i
+
+bb10.i:                                           ; preds = %bb10.i, %bb10.preheader.i
+  br i1 undef, label %bb27.i, label %bb10.i
+
+bb27.i:                                           ; preds = %bb10.i
+  br label %bb28.i
+
+bb28.i:                                           ; preds = %bb28.i, %bb27.i
+  br i1 undef, label %presymmetry.exit, label %bb28.i
+
+presymmetry.exit:                                 ; preds = %bb28.i
+  %tmp175387 = or i32 undef, 12
+  %scevgep101.i = getelementptr i32* %in, i32 undef
+  %tmp189401 = or i32 undef, 7
+  %scevgep97.i = getelementptr i32* %in, i32 undef
+  %tmp198410 = or i32 undef, 1
+  %scevgep.i48 = getelementptr i32* %in, i32 undef
+  %0 = load i32* %scevgep.i48, align 4
+  %1 = add nsw i32 %0, 0
+  store i32 %1, i32* undef, align 4
+  %asmtmp.i.i33.i.i.i = tail call %0 asm "smull\09$0, $1, $2, $3", "=&r,=&r,%r,r,~{cc}"(i32 undef, i32 1518500250) nounwind
+  %asmresult1.i.i34.i.i.i = extractvalue %0 %asmtmp.i.i33.i.i.i, 1
+  %2 = shl i32 %asmresult1.i.i34.i.i.i, 1
+  %3 = load i32* null, align 4
+  %4 = load i32* undef, align 4
+  %5 = sub nsw i32 %3, %4
+  %6 = load i32* undef, align 4
+  %7 = load i32* null, align 4
+  %8 = sub nsw i32 %6, %7
+  %9 = load i32* %scevgep97.i, align 4
+  %10 = load i32* undef, align 4
+  %11 = sub nsw i32 %9, %10
+  %12 = load i32* null, align 4
+  %13 = load i32* %scevgep101.i, align 4
+  %14 = sub nsw i32 %12, %13
+  %15 = load i32* %scevgep.i48, align 4
+  %16 = load i32* null, align 4
+  %17 = add nsw i32 %16, %15
+  %18 = sub nsw i32 %15, %16
+  %19 = load i32* undef, align 4
+  %20 = add nsw i32 %19, %2
+  %21 = sub nsw i32 %19, %2
+  %22 = add nsw i32 %14, %5
+  %23 = sub nsw i32 %5, %14
+  %24 = add nsw i32 %11, %8
+  %25 = sub nsw i32 %8, %11
+  %26 = add nsw i32 %21, %23
+  store i32 %26, i32* %scevgep.i48, align 4
+  %27 = sub nsw i32 %25, %18
+  store i32 %27, i32* null, align 4
+  %28 = sub nsw i32 %23, %21
+  store i32 %28, i32* undef, align 4
+  %29 = add nsw i32 %18, %25
+  store i32 %29, i32* undef, align 4
+  %30 = add nsw i32 %17, %22
+  store i32 %30, i32* %scevgep101.i, align 4
+  %31 = add nsw i32 %20, %24
+  store i32 %31, i32* null, align 4
+  unreachable
+}