[llvm-commits] [llvm] r89246 - in /llvm/trunk: lib/CodeGen/TwoAddressInstructionPass.cpp test/CodeGen/X86/2009-11-18-TwoAddrKill.ll

[Jakob Stoklund Olesen]

Author: stoklund
Date: Wed Nov 18 15:33:35 2009
New Revision: 89246

URL: http://llvm.org/viewvc/llvm-project?rev=89246&view=rev
Log:
Fix PR5300.

When TwoAddressInstructionPass deletes a dead instruction, make sure that all
register kills are accounted for. The 2-addr register does not get special
treatment.

Added:
    llvm/trunk/test/CodeGen/X86/2009-11-18-TwoAddrKill.ll
Modified:
    llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp

Modified: llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp?rev=89246&r1=89245&r2=89246&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp (original)
+++ llvm/trunk/lib/CodeGen/TwoAddressInstructionPass.cpp Wed Nov 18 15:33:35 2009
@@ -112,8 +112,7 @@
                                MachineBasicBlock *MBB, unsigned Dist);
     bool DeleteUnusedInstr(MachineBasicBlock::iterator &mi,
                            MachineBasicBlock::iterator &nmi,
-                           MachineFunction::iterator &mbbi,
-                           unsigned regB, unsigned regBIdx, unsigned Dist);
+                           MachineFunction::iterator &mbbi, unsigned Dist);
 
     bool TryInstructionTransform(MachineBasicBlock::iterator &mi,
                                  MachineBasicBlock::iterator &nmi,
@@ -730,7 +729,7 @@
 
 /// isSafeToDelete - If the specified instruction does not produce any side
 /// effects and all of its defs are dead, then it's safe to delete.
-static bool isSafeToDelete(MachineInstr *MI, unsigned Reg,
+static bool isSafeToDelete(MachineInstr *MI,
                            const TargetInstrInfo *TII,
                            SmallVector<unsigned, 4> &Kills) {
   const TargetInstrDesc &TID = MI->getDesc();
@@ -745,10 +744,9 @@
       continue;
     if (MO.isDef() && !MO.isDead())
       return false;
-    if (MO.isUse() && MO.getReg() != Reg && MO.isKill())
+    if (MO.isUse() && MO.isKill())
       Kills.push_back(MO.getReg());
   }
-
   return true;
 }
 
@@ -783,11 +781,10 @@
 TwoAddressInstructionPass::DeleteUnusedInstr(MachineBasicBlock::iterator &mi,
                                              MachineBasicBlock::iterator &nmi,
                                              MachineFunction::iterator &mbbi,
-                                             unsigned regB, unsigned regBIdx,
                                              unsigned Dist) {
   // Check if the instruction has no side effects and if all its defs are dead.
   SmallVector<unsigned, 4> Kills;
-  if (!isSafeToDelete(mi, regB, TII, Kills))
+  if (!isSafeToDelete(mi, TII, Kills))
     return false;
 
   // If this instruction kills some virtual registers, we need to
@@ -810,10 +807,6 @@
           LV->addVirtualRegisterKilled(Kill, NewKill);
       }
     }
-
-    // If regB was marked as a kill, update its Kills list.
-    if (mi->getOperand(regBIdx).isKill())
-      LV->removeVirtualRegisterKilled(regB, mi);
   }
 
   mbbi->erase(mi); // Nuke the old inst.
@@ -842,7 +835,7 @@
   // it so it doesn't clobber regB.
   bool regBKilled = isKilled(*mi, regB, MRI, TII);
   if (!regBKilled && mi->getOperand(DstIdx).isDead() &&
-      DeleteUnusedInstr(mi, nmi, mbbi, regB, SrcIdx, Dist)) {
+      DeleteUnusedInstr(mi, nmi, mbbi, Dist)) {
     ++NumDeletes;
     return true; // Done with this instruction.
   }

Added: llvm/trunk/test/CodeGen/X86/2009-11-18-TwoAddrKill.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/2009-11-18-TwoAddrKill.ll?rev=89246&view=auto

==============================================================================
--- llvm/trunk/test/CodeGen/X86/2009-11-18-TwoAddrKill.ll (added)
+++ llvm/trunk/test/CodeGen/X86/2009-11-18-TwoAddrKill.ll Wed Nov 18 15:33:35 2009
@@ -0,0 +1,29 @@
+; RUN: llc < %s
+; PR 5300
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32"
+target triple = "i386-pc-linux-gnu"
+
+ at g_296 = external global i8, align 1              ; <i8*> [#uses=1]
+
+define noalias i8** @func_31(i32** nocapture %int8p_33, i8** nocapture %p_34, i8* nocapture %p_35) nounwind {
+entry:
+  %cmp.i = icmp sgt i16 undef, 234                ; <i1> [#uses=1]
+  %tmp17 = select i1 %cmp.i, i16 undef, i16 0     ; <i16> [#uses=2]
+  %conv8 = trunc i16 %tmp17 to i8                 ; <i8> [#uses=3]
+  br i1 undef, label %cond.false.i29, label %land.lhs.true.i
+
+land.lhs.true.i:                                  ; preds = %entry
+  %tobool5.i = icmp eq i32 undef, undef           ; <i1> [#uses=1]
+  br i1 %tobool5.i, label %cond.false.i29, label %bar.exit
+
+cond.false.i29:                                   ; preds = %land.lhs.true.i, %entry
+  %tmp = sub i8 0, %conv8                         ; <i8> [#uses=1]
+  %mul.i = and i8 %conv8, %tmp                    ; <i8> [#uses=1]
+  br label %bar.exit
+
+bar.exit:                                         ; preds = %cond.false.i29, %land.lhs.true.i
+  %call1231 = phi i8 [ %mul.i, %cond.false.i29 ], [ %conv8, %land.lhs.true.i ] ; <i8> [#uses=0]
+  %conv21 = trunc i16 %tmp17 to i8                ; <i8> [#uses=1]
+  store i8 %conv21, i8* @g_296
+  ret i8** undef
+}