Resurrect r191017 " GVN proceeds in the presence of dead code" plus a fix to PR17307 & 17308.

  The problem of r191017 is that when GVN fabricate a val-number for a dead instruction (in order
to make following expr-PRE happy), it forget to fabricate a leader-table entry for it as well.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191118 91177308-0d34-0410-b5e6-96231b3b80d8

8 files changed, 220 insertions, 22 deletions

diff --git a/test/Transforms/GVN/2007-07-26-InterlockingLoops.ll b/test/Transforms/GVN/2007-07-26-InterlockingLoops.ll
index a1cc008..5a15f0e 100644
--- a/test/Transforms/GVN/2007-07-26-InterlockingLoops.ll
+++ b/test/Transforms/GVN/2007-07-26-InterlockingLoops.ll
@@ -2,7 +2,7 @@
 
 @last = external global [65 x i32*]
 
-define i32 @NextRootMove(i32 %wtm) {
+define i32 @NextRootMove(i32 %wtm, i32 %x, i32 %y, i32 %z) {
 entry:
         %A = alloca i32*
 	%tmp17618 = load i32** getelementptr ([65 x i32*]* @last, i32 0, i32 1), align 4
@@ -15,12 +15,14 @@ entry:
 	br label %cond_true116
 
 cond_true116:
-	br i1 false, label %cond_true128, label %cond_true145
+   %cmp = icmp eq i32 %x, %y
+	br i1 %cmp, label %cond_true128, label %cond_true145
 
 cond_true128:
 	%tmp17625 = load i32** getelementptr ([65 x i32*]* @last, i32 0, i32 1), align 4
         store i32* %tmp17625, i32** %A
-	br i1 false, label %bb98.backedge, label %return.loopexit
+   %cmp1 = icmp eq i32 %x, %z
+	br i1 %cmp1 , label %bb98.backedge, label %return.loopexit
 
 bb98.backedge:
 	br label %cond_true116
diff --git a/test/Transforms/GVN/2008-07-02-Unreachable.ll b/test/Transforms/GVN/2008-07-02-Unreachable.ll
index 4f07868..ce83fa4 100644
--- a/test/Transforms/GVN/2008-07-02-Unreachable.ll
+++ b/test/Transforms/GVN/2008-07-02-Unreachable.ll
@@ -3,10 +3,11 @@
 
 @g_3 = external global i8		; <i8*> [#uses=2]
 
-define i8 @func_1() nounwind  {
+define i8 @func_1(i32 %x, i32 %y) nounwind  {
 entry:
   %A = alloca i8
-	br i1 false, label %ifelse, label %ifthen
+    %cmp = icmp eq i32 %x, %y
+	br i1 %cmp, label %ifelse, label %ifthen
 
 ifthen:		; preds = %entry
 	br label %ifend
@@ -14,9 +15,6 @@ ifthen:		; preds = %entry
 ifelse:		; preds = %entry
 	%tmp3 = load i8* @g_3		; <i8> [#uses=0]
         store i8 %tmp3, i8* %A
-	br label %forcond.thread
-
-forcond.thread:		; preds = %ifelse
 	br label %afterfor
 
 forcond:		; preds = %forinc
diff --git a/test/Transforms/GVN/cond_br.ll b/test/Transforms/GVN/cond_br.ll
new file mode 100644
index 0000000..918e7d4
--- /dev/null
+++ b/test/Transforms/GVN/cond_br.ll
@@ -0,0 +1,55 @@
+; RUN: opt -basicaa -gvn -S < %s | FileCheck %s
+@y = external global i32
+@z = external global i32
+
+; Function Attrs: nounwind ssp uwtable
+define void @foo(i32 %x) {
+; CHECK: @foo(i32 %x)
+; CHECK: %.pre = load i32* @y
+; CHECK: call void @bar(i32 %.pre)
+
+  %t = sub i32 %x, %x
+  %.pre = load i32* @y, align 4
+  %cmp = icmp sgt i32 %t, 2
+  br i1 %cmp, label %if.then, label %entry.if.end_crit_edge
+
+entry.if.end_crit_edge:                           ; preds = %entry
+  br label %if.end
+
+if.then:                                          ; preds = %entry
+  %add = add nsw i32 %x, 3
+  store i32 %add, i32* @y, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %entry.if.end_crit_edge, %if.then
+  %1 = phi i32 [ %.pre, %entry.if.end_crit_edge ], [ %add, %if.then ]
+  tail call void @bar(i32 %1)
+  ret void
+}
+
+define void @foo2(i32 %x) {
+; CHECK: @foo2(i32 %x)
+; CHECK: %.pre = load i32* @y
+; CHECK: tail call void @bar(i32 %.pre)
+entry:
+  %t = sub i32 %x, %x
+  %.pre = load i32* @y, align 4
+  %cmp = icmp sgt i32 %t, 2
+  br i1 %cmp, label %if.then, label %if.else
+
+if.then:                                          ; preds = %entry
+  %add = add nsw i32 %x, 3
+  store i32 %add, i32* @y, align 4
+  br label %if.end
+
+if.else:                                          ; preds = %entry
+  store i32 1, i32* @z, align 4
+  br label %if.end
+
+if.end:                                           ; preds = %if.else, %if.then
+  %0 = phi i32 [ %.pre, %if.else ], [ %add, %if.then ]
+  tail call void @bar(i32 %0)
+  ret void
+}
+
+declare void @bar(i32)
diff --git a/test/Transforms/GVN/cond_br2.ll b/test/Transforms/GVN/cond_br2.ll
new file mode 100644
index 0000000..e0ef39d
--- /dev/null
+++ b/test/Transforms/GVN/cond_br2.ll
@@ -0,0 +1,139 @@
+; RUN: opt -basicaa -gvn -S < %s | FileCheck %s
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+
+%"class.llvm::SmallVector" = type { %"class.llvm::SmallVectorImpl", [1 x %"union.llvm::SmallVectorBase::U"] }
+%"class.llvm::SmallVectorImpl" = type { %"class.llvm::SmallVectorTemplateBase" }
+%"class.llvm::SmallVectorTemplateBase" = type { %"class.llvm::SmallVectorTemplateCommon" }
+%"class.llvm::SmallVectorTemplateCommon" = type { %"class.llvm::SmallVectorBase" }
+%"class.llvm::SmallVectorBase" = type { i8*, i8*, i8*, %"union.llvm::SmallVectorBase::U" }
+%"union.llvm::SmallVectorBase::U" = type { x86_fp80 }
+
+; Function Attrs: ssp uwtable
+define void @_Z4testv() #0 {
+; CHECK: @_Z4testv()
+; CHECK: invoke.cont:
+; CHECK: br i1 true, label %new.notnull.i11, label %if.end.i14
+; CHECK: Retry.i10:
+
+entry:
+  %sv = alloca %"class.llvm::SmallVector", align 16
+  %0 = bitcast %"class.llvm::SmallVector"* %sv to i8*
+  call void @llvm.lifetime.start(i64 64, i8* %0) #1
+  %BeginX.i.i.i.i.i.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 0
+  %FirstEl.i.i.i.i.i.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 3
+  %1 = bitcast %"union.llvm::SmallVectorBase::U"* %FirstEl.i.i.i.i.i.i to i8*
+  store i8* %1, i8** %BeginX.i.i.i.i.i.i, align 16, !tbaa !0
+  %EndX.i.i.i.i.i.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 1
+  store i8* %1, i8** %EndX.i.i.i.i.i.i, align 8, !tbaa !0
+  %CapacityX.i.i.i.i.i.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 2
+  %add.ptr.i.i.i.i2.i.i = getelementptr inbounds %"union.llvm::SmallVectorBase::U"* %FirstEl.i.i.i.i.i.i, i64 2
+  %add.ptr.i.i.i.i.i.i = bitcast %"union.llvm::SmallVectorBase::U"* %add.ptr.i.i.i.i2.i.i to i8*
+  store i8* %add.ptr.i.i.i.i.i.i, i8** %CapacityX.i.i.i.i.i.i, align 16, !tbaa !0
+  %EndX.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 1
+  %2 = load i8** %EndX.i, align 8, !tbaa !0
+  %CapacityX.i = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0, i32 2
+  %cmp.i = icmp ult i8* %2, %add.ptr.i.i.i.i.i.i
+  br i1 %cmp.i, label %Retry.i, label %if.end.i
+
+Retry.i:                                          ; preds = %.noexc, %entry
+  %3 = phi i8* [ %2, %entry ], [ %.pre.i, %.noexc ]
+  %new.isnull.i = icmp eq i8* %3, null
+  br i1 %new.isnull.i, label %invoke.cont, label %new.notnull.i
+
+new.notnull.i:                                    ; preds = %Retry.i
+  %4 = bitcast i8* %3 to i32*
+  store i32 1, i32* %4, align 4, !tbaa !3
+  br label %invoke.cont
+
+if.end.i:                                         ; preds = %entry
+  %5 = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0
+  invoke void @_ZN4llvm15SmallVectorBase8grow_podEmm(%"class.llvm::SmallVectorBase"* %5, i64 0, i64 4)
+          to label %.noexc unwind label %lpad
+
+.noexc:                                           ; preds = %if.end.i
+  %.pre.i = load i8** %EndX.i, align 8, !tbaa !0
+  br label %Retry.i
+
+invoke.cont:                                      ; preds = %new.notnull.i, %Retry.i
+  %add.ptr.i = getelementptr inbounds i8* %3, i64 4
+  store i8* %add.ptr.i, i8** %EndX.i, align 8, !tbaa !0
+  %6 = load i8** %CapacityX.i, align 16, !tbaa !0
+  %cmp.i8 = icmp ult i8* %add.ptr.i, %6
+  br i1 %cmp.i8, label %new.notnull.i11, label %if.end.i14
+
+Retry.i10:                                        ; preds = %if.end.i14
+  %.pre.i13 = load i8** %EndX.i, align 8, !tbaa !0
+  %new.isnull.i9 = icmp eq i8* %.pre.i13, null
+  br i1 %new.isnull.i9, label %invoke.cont2, label %new.notnull.i11
+
+new.notnull.i11:                                  ; preds = %invoke.cont, %Retry.i10
+  %7 = phi i8* [ %.pre.i13, %Retry.i10 ], [ %add.ptr.i, %invoke.cont ]
+  %8 = bitcast i8* %7 to i32*
+  store i32 2, i32* %8, align 4, !tbaa !3
+  br label %invoke.cont2
+
+if.end.i14:                                       ; preds = %invoke.cont
+  %9 = getelementptr inbounds %"class.llvm::SmallVector"* %sv, i64 0, i32 0, i32 0, i32 0, i32 0
+  invoke void @_ZN4llvm15SmallVectorBase8grow_podEmm(%"class.llvm::SmallVectorBase"* %9, i64 0, i64 4)
+          to label %Retry.i10 unwind label %lpad
+
+invoke.cont2:                                     ; preds = %new.notnull.i11, %Retry.i10
+  %10 = phi i8* [ null, %Retry.i10 ], [ %7, %new.notnull.i11 ]
+  %add.ptr.i12 = getelementptr inbounds i8* %10, i64 4
+  store i8* %add.ptr.i12, i8** %EndX.i, align 8, !tbaa !0
+  invoke void @_Z1gRN4llvm11SmallVectorIiLj8EEE(%"class.llvm::SmallVector"* %sv)
+          to label %invoke.cont3 unwind label %lpad
+
+invoke.cont3:                                     ; preds = %invoke.cont2
+  %11 = load i8** %BeginX.i.i.i.i.i.i, align 16, !tbaa !0
+  %cmp.i.i.i.i19 = icmp eq i8* %11, %1
+  br i1 %cmp.i.i.i.i19, label %_ZN4llvm11SmallVectorIiLj8EED1Ev.exit21, label %if.then.i.i.i20
+
+if.then.i.i.i20:                                  ; preds = %invoke.cont3
+  call void @free(i8* %11) #1
+  br label %_ZN4llvm11SmallVectorIiLj8EED1Ev.exit21
+
+_ZN4llvm11SmallVectorIiLj8EED1Ev.exit21:          ; preds = %invoke.cont3, %if.then.i.i.i20
+  call void @llvm.lifetime.end(i64 64, i8* %0) #1
+  ret void
+
+lpad:                                             ; preds = %if.end.i14, %if.end.i, %invoke.cont2
+  %12 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
+          cleanup
+  %13 = load i8** %BeginX.i.i.i.i.i.i, align 16, !tbaa !0
+  %cmp.i.i.i.i = icmp eq i8* %13, %1
+  br i1 %cmp.i.i.i.i, label %eh.resume, label %if.then.i.i.i
+
+if.then.i.i.i:                                    ; preds = %lpad
+  call void @free(i8* %13) #1
+  br label %eh.resume
+
+eh.resume:                                        ; preds = %if.then.i.i.i, %lpad
+  resume { i8*, i32 } %12
+}
+
+; Function Attrs: nounwind
+declare void @llvm.lifetime.start(i64, i8* nocapture) #1
+
+declare i32 @__gxx_personality_v0(...)
+
+declare void @_Z1gRN4llvm11SmallVectorIiLj8EEE(%"class.llvm::SmallVector"*) #2
+
+; Function Attrs: nounwind
+declare void @llvm.lifetime.end(i64, i8* nocapture) #1
+
+declare void @_ZN4llvm15SmallVectorBase8grow_podEmm(%"class.llvm::SmallVectorBase"*, i64, i64) #2
+
+; Function Attrs: nounwind
+declare void @free(i8* nocapture) #3
+
+attributes #0 = { ssp uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind }
+attributes #2 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #3 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!0 = metadata !{metadata !"any pointer", metadata !1}
+!1 = metadata !{metadata !"omnipotent char", metadata !2}
+!2 = metadata !{metadata !"Simple C/C++ TBAA"}
+!3 = metadata !{metadata !"int", metadata !1}
+
diff --git a/test/Transforms/GVN/local-pre.ll b/test/Transforms/GVN/local-pre.ll
index 1d0dadf..2c92699 100644
--- a/test/Transforms/GVN/local-pre.ll
+++ b/test/Transforms/GVN/local-pre.ll
@@ -1,9 +1,9 @@
 ; RUN: opt < %s -gvn -enable-pre -S | grep "b.pre"
 
-define i32 @main(i32 %p) {
+define i32 @main(i32 %p, i32 %q) {
 block1:
-  
-	br i1 true, label %block2, label %block3
+    %cmp = icmp eq i32 %p, %q 
+	br i1 %cmp, label %block2, label %block3
 
 block2:
  %a = add i32 %p, 1
diff --git a/test/Transforms/GVN/rle-nonlocal.ll b/test/Transforms/GVN/rle-nonlocal.ll
index 6b74e9a..8229aaa 100644
--- a/test/Transforms/GVN/rle-nonlocal.ll
+++ b/test/Transforms/GVN/rle-nonlocal.ll
@@ -1,8 +1,9 @@
 ; RUN: opt < %s -basicaa -gvn -S | FileCheck %s
 
-define i32 @main(i32** %p) {
+define i32 @main(i32** %p, i32 %x, i32 %y) {
 block1:
-	br i1 true, label %block2, label %block3
+    %cmp = icmp eq i32 %x, %y
+	br i1 %cmp , label %block2, label %block3
 
 block2:
  %a = load i32** %p
diff --git a/test/Transforms/GVN/rle-semidominated.ll b/test/Transforms/GVN/rle-semidominated.ll
index 71aa548..923cd03 100644
--- a/test/Transforms/GVN/rle-semidominated.ll
+++ b/test/Transforms/GVN/rle-semidominated.ll
@@ -1,9 +1,10 @@
 ; RUN: opt < %s -basicaa -gvn -S | grep "DEAD = phi i32 "
 
-define i32 @main(i32* %p) {
+define i32 @main(i32* %p, i32 %x, i32 %y) {
 block1:
   %z = load i32* %p
-	br i1 true, label %block2, label %block3
+  %cmp = icmp eq i32 %x, %y
+	br i1 %cmp, label %block2, label %block3
 
 block2:
  br label %block4
diff --git a/test/Transforms/GVN/rle.ll b/test/Transforms/GVN/rle.ll
index 8787dd5..a928a16 100644
--- a/test/Transforms/GVN/rle.ll
+++ b/test/Transforms/GVN/rle.ll
@@ -357,13 +357,14 @@ Cont:
 ; CHECK: ret i8 %A
 }
 
-define i32 @chained_load(i32** %p) {
+define i32 @chained_load(i32** %p, i32 %x, i32 %y) {
 block1:
   %A = alloca i32*
 
   %z = load i32** %p
   store i32* %z, i32** %A
-  br i1 true, label %block2, label %block3
+  %cmp = icmp eq i32 %x, %y
+  br i1 %cmp, label %block2, label %block3
 
 block2:
  %a = load i32** %p
@@ -427,10 +428,11 @@ TY:
   ret i32 0
 }
 
-define i32 @phi_trans3(i32* %p) {
+define i32 @phi_trans3(i32* %p, i32 %x, i32 %y, i32 %z) {
 ; CHECK-LABEL: @phi_trans3(
 block1:
-  br i1 true, label %block2, label %block3
+  %cmpxy = icmp eq i32 %x, %y
+  br i1 %cmpxy, label %block2, label %block3
 
 block2:
  store i32 87, i32* %p
@@ -443,7 +445,7 @@ block3:
 
 block4:
   %A = phi i32 [-1, %block2], [42, %block3]
-  br i1 true, label %block5, label %exit
+  br i1 %cmpxy, label %block5, label %exit
   
 ; CHECK: block4:
 ; CHECK-NEXT: %D = phi i32 [ 87, %block2 ], [ 97, %block3 ]  
@@ -451,11 +453,11 @@ block4:
 
 block5:
   %B = add i32 %A, 1
-  br i1 true, label %block6, label %exit
+  br i1 %cmpxy, label %block6, label %exit
   
 block6:
   %C = getelementptr i32* %p, i32 %B
-  br i1 true, label %block7, label %exit
+  br i1 %cmpxy, label %block7, label %exit
   
 block7:
   %D = load i32* %C