Another nasty coalescer bug (is there another kind):

After coalescing reg1027's def and kill are both at the same point:
 %reg1027,0.000000e+00 = [56,814:0)  0@70-(814)

bb5:
60   %reg1027<def> = t2MOVr %reg1027, 14, %reg0, %reg0
68   %reg1027<def> = t2LDRi12 %reg1027<kill>, 8, 14, %reg0
76   t2CMPzri %reg1038<kill,undef>, 0, 14, %reg0, %CPSR<imp-def>
84   %reg1027<def> = t2MOVr %reg1027, 14, %reg0, %reg0
96   t2Bcc mbb<bb5,0x2030910>, 1, %CPSR<kill>

Do not remove the kill marker on t2LDRi12.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78178 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp
index a2d521b139a63398963d1173dfa16fcd72531c40..08e0bcf85b664ce7af8810ae6cdb2789f6e1f925 100644 (file)
--- a/lib/CodeGen/SimpleRegisterCoalescing.cpp
+++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp
@@ -804,12 +804,26 @@ void SimpleRegisterCoalescing::RemoveUnnecessaryKills(unsigned Reg,
   for (MachineRegisterInfo::use_iterator UI = mri_->use_begin(Reg),
          UE = mri_->use_end(); UI != UE; ++UI) {
     MachineOperand &UseMO = UI.getOperand();
-    if (UseMO.isKill()) {
-      MachineInstr *UseMI = UseMO.getParent();
-      unsigned UseIdx = li_->getUseIndex(li_->getInstructionIndex(UseMI));
-      const LiveRange *UI = LI.getLiveRangeContaining(UseIdx);
-      if (!UI || !LI.isKill(UI->valno, UseIdx+1))
+    if (!UseMO.isKill())
+      continue;
+    MachineInstr *UseMI = UseMO.getParent();
+    unsigned UseIdx = li_->getUseIndex(li_->getInstructionIndex(UseMI));
+    const LiveRange *UI = LI.getLiveRangeContaining(UseIdx);
+    if (!UI || !LI.isKill(UI->valno, UseIdx+1)) {
+      if (UI->valno->def != UseIdx+1) {
+        // Interesting problem. After coalescing reg1027's def and kill are both
+        // at the same point:  %reg1027,0.000000e+00 = [56,814:0)  0@70-(814)
+        //
+        // bb5:
+        // 60  %reg1027<def> = t2MOVr %reg1027, 14, %reg0, %reg0
+        // 68  %reg1027<def> = t2LDRi12 %reg1027<kill>, 8, 14, %reg0
+        // 76  t2CMPzri %reg1038<kill,undef>, 0, 14, %reg0, %CPSR<imp-def>
+        // 84  %reg1027<def> = t2MOVr %reg1027, 14, %reg0, %reg0
+        // 96  t2Bcc mbb<bb5,0x2030910>, 1, %CPSR<kill>
+        //
+        // Do not remove the kill marker on t2LDRi12.
         UseMO.setIsKill(false);
+      }
     }
   }
 }

diff --git a/test/CodeGen/Thumb2/2009-08-04-CoalescerBug.ll b/test/CodeGen/Thumb2/2009-08-04-CoalescerBug.ll
new file mode 100644 (file)
index 0000000..55e24df
--- /dev/null
+++ b/test/CodeGen/Thumb2/2009-08-04-CoalescerBug.ll
@@ -0,0 +1,153 @@
+; RUN: llvm-as < %s | llc -mtriple=thumbv7-apple-darwin -mattr=+neon,+neonfp -relocation-model=pic -disable-fp-elim
+
+       type { %struct.GAP }            ; type %0
+       type { i16, i8, i8 }            ; type %1
+       type { [2 x i32], [2 x i32] }           ; type %2
+       type { %struct.rec* }           ; type %3
+       type { i8, i8, i16, i8, i8, i8, i8 }            ; type %4
+       %struct.FILE = type { i8*, i32, i32, i16, i16, %struct.__sbuf, i32, i8*, i32 (i8*)*, i32 (i8*, i8*, i32)*, i64 (i8*, i64, i32)*, i32 (i8*, i8*, i32)*, %struct.__sbuf, %struct.__sFILEX*, i32, [3 x i8], [1 x i8], %struct.__sbuf, i32, i64 }
+       %struct.FILE_POS = type { i8, i8, i16, i32 }
+       %struct.FIRST_UNION = type { %struct.FILE_POS }
+       %struct.FOURTH_UNION = type { %struct.STYLE }
+       %struct.GAP = type { i8, i8, i16 }
+       %struct.LIST = type { %struct.rec*, %struct.rec* }
+       %struct.SECOND_UNION = type { %1 }
+       %struct.STYLE = type { %0, %0, i16, i16, i32 }
+       %struct.THIRD_UNION = type { %2 }
+       %struct.__sFILEX = type opaque
+       %struct.__sbuf = type { i8*, i32 }
+       %struct.head_type = type { [2 x %struct.LIST], %struct.FIRST_UNION, %struct.SECOND_UNION, %struct.THIRD_UNION, %struct.FOURTH_UNION, %struct.rec*, %3, %struct.rec*, %struct.rec*, %struct.rec*, %struct.rec*, %struct.rec*, %struct.rec*, %struct.rec*, %struct.rec*, i32 }
+       %struct.rec = type { %struct.head_type }
+@.str24239 = external constant [20 x i8], align 1              ; <[20 x i8]*> [#uses=1]
+@no_file_pos = external global %4              ; <%4*> [#uses=1]
+@zz_tmp = external global %struct.rec*         ; <%struct.rec**> [#uses=1]
+@.str81872 = external constant [10 x i8], align 1              ; <[10 x i8]*> [#uses=1]
+@out_fp = external global %struct.FILE*                ; <%struct.FILE**> [#uses=2]
+@cpexists = external global i32                ; <i32*> [#uses=2]
+@.str212784 = external constant [17 x i8], align 1             ; <[17 x i8]*> [#uses=1]
+@.str1822946 = external constant [8 x i8], align 1             ; <[8 x i8]*> [#uses=1]
+@.str1842948 = external constant [11 x i8], align 1            ; <[11 x i8]*> [#uses=1]
+
+declare arm_apcscc i32 @fprintf(%struct.FILE* nocapture, i8* nocapture, ...) nounwind
+
+declare arm_apcscc i32 @"\01_fwrite"(i8*, i32, i32, i8*)
+
+declare arm_apcscc %struct.FILE* @OpenIncGraphicFile(i8*, i8 zeroext, %struct.rec** nocapture, %struct.FILE_POS*, i32* nocapture) nounwind
+
+declare arm_apcscc void @Error(i32, i32, i8*, i32, %struct.FILE_POS*, ...) nounwind
+
+declare arm_apcscc i8* @fgets(i8*, i32, %struct.FILE* nocapture) nounwind
+
+define arm_apcscc void @PS_PrintGraphicInclude(%struct.rec* %x, i32 %colmark, i32 %rowmark) nounwind {
+entry:
+       br label %bb5
+
+bb5:           ; preds = %bb5, %entry
+       %.pn = phi %struct.rec* [ %y.0, %bb5 ], [ undef, %entry ]               ; <%struct.rec*> [#uses=1]
+       %y.0.in = getelementptr %struct.rec* %.pn, i32 0, i32 0, i32 0, i32 1, i32 0            ; <%struct.rec**> [#uses=1]
+       %y.0 = load %struct.rec** %y.0.in               ; <%struct.rec*> [#uses=2]
+       br i1 undef, label %bb5, label %bb6
+
+bb6:           ; preds = %bb5
+       %0 = call arm_apcscc  %struct.FILE* @OpenIncGraphicFile(i8* undef, i8 zeroext 0, %struct.rec** undef, %struct.FILE_POS* null, i32* undef) nounwind              ; <%struct.FILE*> [#uses=1]
+       br i1 false, label %bb.i, label %FontHalfXHeight.exit
+
+bb.i:          ; preds = %bb6
+       br label %FontHalfXHeight.exit
+
+FontHalfXHeight.exit:          ; preds = %bb.i, %bb6
+       br i1 undef, label %bb.i1, label %FontSize.exit
+
+bb.i1:         ; preds = %FontHalfXHeight.exit
+       br label %FontSize.exit
+
+FontSize.exit:         ; preds = %bb.i1, %FontHalfXHeight.exit
+       %1 = load i32* undef, align 4           ; <i32> [#uses=1]
+       %2 = icmp ult i32 0, undef              ; <i1> [#uses=1]
+       br i1 %2, label %bb.i5, label %FontName.exit
+
+bb.i5:         ; preds = %FontSize.exit
+       call arm_apcscc  void (i32, i32, i8*, i32, %struct.FILE_POS*, ...)* @Error(i32 1, i32 2, i8* getelementptr ([20 x i8]* @.str24239, i32 0, i32 0), i32 0, %struct.FILE_POS* bitcast (%4* @no_file_pos to %struct.FILE_POS*), i8* getelementptr ([10 x i8]* @.str81872, i32 0, i32 0)) nounwind
+       br label %FontName.exit
+
+FontName.exit:         ; preds = %bb.i5, %FontSize.exit
+       %3 = call arm_apcscc  i32 (%struct.FILE*, i8*, ...)* @fprintf(%struct.FILE* undef, i8* getelementptr ([8 x i8]* @.str1822946, i32 0, i32 0), i32 %1, i8* undef) nounwind                ; <i32> [#uses=0]
+       %4 = call arm_apcscc  i32 @"\01_fwrite"(i8* getelementptr ([11 x i8]* @.str1842948, i32 0, i32 0), i32 1, i32 10, i8* undef) nounwind           ; <i32> [#uses=0]
+       %5 = sub i32 %colmark, undef            ; <i32> [#uses=1]
+       %6 = sub i32 %rowmark, undef            ; <i32> [#uses=1]
+       %7 = load %struct.FILE** @out_fp, align 4               ; <%struct.FILE*> [#uses=1]
+       %8 = call arm_apcscc  i32 (%struct.FILE*, i8*, ...)* @fprintf(%struct.FILE* %7, i8* getelementptr ([17 x i8]* @.str212784, i32 0, i32 0), i32 %5, i32 %6) nounwind              ; <i32> [#uses=0]
+       store i32 0, i32* @cpexists, align 4
+       %9 = getelementptr %struct.rec* %y.0, i32 0, i32 0, i32 3, i32 0, i32 0, i32 1          ; <i32*> [#uses=1]
+       %10 = load i32* %9, align 4             ; <i32> [#uses=1]
+       %11 = sub i32 0, %10            ; <i32> [#uses=1]
+       %12 = load %struct.FILE** @out_fp, align 4              ; <%struct.FILE*> [#uses=1]
+       %13 = call arm_apcscc  i32 (%struct.FILE*, i8*, ...)* @fprintf(%struct.FILE* %12, i8* getelementptr ([17 x i8]* @.str212784, i32 0, i32 0), i32 undef, i32 %11) nounwind                ; <i32> [#uses=0]
+       store i32 0, i32* @cpexists, align 4
+       br label %bb100.outer.outer
+
+bb100.outer.outer:             ; preds = %bb79.critedge, %bb1.i3, %FontName.exit
+       %x_addr.0.ph.ph = phi %struct.rec* [ %x, %FontName.exit ], [ null, %bb79.critedge ], [ null, %bb1.i3 ]          ; <%struct.rec*> [#uses=1]
+       %14 = getelementptr %struct.rec* %x_addr.0.ph.ph, i32 0, i32 0, i32 1, i32 0            ; <%struct.FILE_POS*> [#uses=0]
+       br label %bb100.outer
+
+bb.i80:                ; preds = %bb3.i85
+       br i1 undef, label %bb2.i84, label %bb2.i51
+
+bb2.i84:               ; preds = %bb100.outer, %bb.i80
+       br i1 undef, label %bb3.i77, label %bb3.i85
+
+bb3.i85:               ; preds = %bb2.i84
+       br i1 false, label %StringBeginsWith.exit88, label %bb.i80
+
+StringBeginsWith.exit88:               ; preds = %bb3.i85
+       br i1 undef, label %bb3.i77, label %bb2.i51
+
+bb2.i.i68:             ; preds = %bb3.i77
+       br label %bb3.i77
+
+bb3.i77:               ; preds = %bb2.i.i68, %StringBeginsWith.exit88, %bb2.i84
+       br i1 false, label %bb1.i58, label %bb2.i.i68
+
+bb1.i58:               ; preds = %bb3.i77
+       unreachable
+
+bb.i47:                ; preds = %bb3.i52
+       br i1 undef, label %bb2.i51, label %bb2.i.i15.critedge
+
+bb2.i51:               ; preds = %bb.i47, %StringBeginsWith.exit88, %bb.i80
+       %15 = load i8* undef, align 1           ; <i8> [#uses=0]
+       br i1 false, label %StringBeginsWith.exit55thread-split, label %bb3.i52
+
+bb3.i52:               ; preds = %bb2.i51
+       br i1 false, label %StringBeginsWith.exit55, label %bb.i47
+
+StringBeginsWith.exit55thread-split:           ; preds = %bb2.i51
+       br label %StringBeginsWith.exit55
+
+StringBeginsWith.exit55:               ; preds = %StringBeginsWith.exit55thread-split, %bb3.i52
+       br label %bb2.i41
+
+bb2.i41:               ; preds = %bb2.i41, %StringBeginsWith.exit55
+       br label %bb2.i41
+
+bb2.i.i15.critedge:            ; preds = %bb.i47
+       %16 = call arm_apcscc  i8* @fgets(i8* undef, i32 512, %struct.FILE* %0) nounwind                ; <i8*> [#uses=0]
+       %iftmp.560.0 = select i1 undef, i32 2, i32 0            ; <i32> [#uses=1]
+       br label %bb100.outer
+
+bb2.i8:                ; preds = %bb100.outer
+       br i1 undef, label %bb1.i3, label %bb79.critedge
+
+bb1.i3:                ; preds = %bb2.i8
+       br label %bb100.outer.outer
+
+bb79.critedge:         ; preds = %bb2.i8
+       store %struct.rec* null, %struct.rec** @zz_tmp, align 4
+       br label %bb100.outer.outer
+
+bb100.outer:           ; preds = %bb2.i.i15.critedge, %bb100.outer.outer
+       %state.0.ph = phi i32 [ 0, %bb100.outer.outer ], [ %iftmp.560.0, %bb2.i.i15.critedge ]          ; <i32> [#uses=1]
+       %cond = icmp eq i32 %state.0.ph, 1              ; <i1> [#uses=1]
+       br i1 %cond, label %bb2.i8, label %bb2.i84
+}