1 files changed, 129 insertions, 20 deletions
diff --git a/test/Transforms/InstCombine/phi.ll b/test/Transforms/InstCombine/phi.ll
index 24eca72..b73ce3f 100644
--- a/test/Transforms/InstCombine/phi.ll
+++ b/test/Transforms/InstCombine/phi.ll
@@ -1,44 +1,53 @@
 ; This test makes sure that these instructions are properly eliminated.
 ;
-; RUN: opt < %s -instcombine -S | not grep phi
+; RUN: opt < %s -instcombine -S | FileCheck %s
 
 define i32 @test1(i32 %A, i1 %b) {
 BB0:
         br i1 %b, label %BB1, label %BB2
 
-BB1:            ; preds = %BB0
+BB1:
         ; Combine away one argument PHI nodes
-        %B = phi i32 [ %A, %BB0 ]               ; <i32> [#uses=1]
+        %B = phi i32 [ %A, %BB0 ]               
         ret i32 %B
 
-BB2:            ; preds = %BB0
+BB2:
         ret i32 %A
+; CHECK: @test1
+; CHECK: BB1:
+; CHECK-NEXT: ret i32 %A
 }
 
 define i32 @test2(i32 %A, i1 %b) {
 BB0:
         br i1 %b, label %BB1, label %BB2
 
-BB1:            ; preds = %BB0
+BB1:
         br label %BB2
 
-BB2:            ; preds = %BB1, %BB0
+BB2:
         ; Combine away PHI nodes with same values
-        %B = phi i32 [ %A, %BB0 ], [ %A, %BB1 ]         ; <i32> [#uses=1]
+        %B = phi i32 [ %A, %BB0 ], [ %A, %BB1 ]         
         ret i32 %B
+; CHECK: @test2
+; CHECK: BB2:
+; CHECK-NEXT: ret i32 %A
 }
 
 define i32 @test3(i32 %A, i1 %b) {
 BB0:
         br label %Loop
 
-Loop:           ; preds = %Loop, %BB0
+Loop:
         ; PHI has same value always.
-        %B = phi i32 [ %A, %BB0 ], [ %B, %Loop ]                ; <i32> [#uses=2]
+        %B = phi i32 [ %A, %BB0 ], [ %B, %Loop ]
         br i1 %b, label %Loop, label %Exit
 
-Exit:           ; preds = %Loop
+Exit:
         ret i32 %B
+; CHECK: @test3
+; CHECK: Exit:
+; CHECK-NEXT: ret i32 %A
 }
 
 define i32 @test4(i1 %b) {
@@ -48,11 +57,14 @@ BB0:
 
 Loop:           ; preds = %L2, %Loop
         ; PHI has same value always.
-        %B = phi i32 [ %B, %L2 ], [ %B, %Loop ]         ; <i32> [#uses=2]
+        %B = phi i32 [ %B, %L2 ], [ %B, %Loop ]         
         br i1 %b, label %L2, label %Loop
 
 L2:             ; preds = %Loop
         br label %Loop
+; CHECK: @test4
+; CHECK: Loop:
+; CHECK-NEXT: br i1 %b
 }
 
 define i32 @test5(i32 %A, i1 %b) {
@@ -61,26 +73,35 @@ BB0:
 
 Loop:           ; preds = %Loop, %BB0
         ; PHI has same value always.
-        %B = phi i32 [ %A, %BB0 ], [ undef, %Loop ]             ; <i32> [#uses=1]
+        %B = phi i32 [ %A, %BB0 ], [ undef, %Loop ]             
         br i1 %b, label %Loop, label %Exit
 
 Exit:           ; preds = %Loop
         ret i32 %B
+; CHECK: @test5
+; CHECK: Loop:
+; CHECK-NEXT: br i1 %b
+; CHECK: Exit:
+; CHECK-NEXT: ret i32 %A
 }
 
-define i32 @test6(i32 %A, i1 %b) {
+define i32 @test6(i16 %A, i1 %b) {
 BB0:
-        %X = bitcast i32 %A to i32              ; <i32> [#uses=1]
+        %X = zext i16 %A to i32              
         br i1 %b, label %BB1, label %BB2
 
-BB1:            ; preds = %BB0
-        %Y = bitcast i32 %A to i32              ; <i32> [#uses=1]
+BB1:           
+        %Y = zext i16 %A to i32              
         br label %BB2
 
-BB2:            ; preds = %BB1, %BB0
+BB2:           
         ;; Suck casts into phi
-        %B = phi i32 [ %X, %BB0 ], [ %Y, %BB1 ]         ; <i32> [#uses=1]
+        %B = phi i32 [ %X, %BB0 ], [ %Y, %BB1 ]         
         ret i32 %B
+; CHECK: @test6
+; CHECK: BB2:
+; CHECK: zext i16 %A to i32
+; CHECK-NEXT: ret i32
 }
 
 define i32 @test7(i32 %A, i1 %b) {
@@ -89,12 +110,15 @@ BB0:
 
 Loop:           ; preds = %Loop, %BB0
         ; PHI is dead.
-        %B = phi i32 [ %A, %BB0 ], [ %C, %Loop ]                ; <i32> [#uses=1]
-        %C = add i32 %B, 123            ; <i32> [#uses=1]
+        %B = phi i32 [ %A, %BB0 ], [ %C, %Loop ]                
+        %C = add i32 %B, 123            
         br i1 %b, label %Loop, label %Exit
 
 Exit:           ; preds = %Loop
         ret i32 0
+; CHECK: @test7
+; CHECK: Loop:
+; CHECK-NEXT: br i1 %b
 }
 
 define i32* @test8({ i32, i32 } *%A, i1 %b) {
@@ -110,6 +134,91 @@ BB2:
         ;; Suck GEPs into phi
         %B = phi i32* [ %X, %BB0 ], [ %Y, %BB1 ]
         ret i32* %B
+; CHECK: @test8
+; CHECK-NOT: phi
+; CHECK: BB2:
+; CHECK-NEXT: %B = getelementptr 
+; CHECK-NEXT: ret i32* %B
+}
+
+define i32 @test9(i32* %A, i32* %B) {
+entry:
+  %c = icmp eq i32* %A, null
+  br i1 %c, label %bb1, label %bb
+
+bb:
+  %C = load i32* %B, align 1
+  br label %bb2
+
+bb1:
+  %D = load i32* %A, align 1
+  br label %bb2
+
+bb2:
+  %E = phi i32 [ %C, %bb ], [ %D, %bb1 ]
+  ret i32 %E
+; CHECK: @test9
+; CHECK:       bb2:
+; CHECK-NEXT:        phi i32* [ %B, %bb ], [ %A, %bb1 ]
+; CHECK-NEXT:   %E = load i32* %{{[^,]*}}, align 1
+; CHECK-NEXT:   ret i32 %E
+
 }
 
+define i32 @test10(i32* %A, i32* %B) {
+entry:
+  %c = icmp eq i32* %A, null
+  br i1 %c, label %bb1, label %bb
+
+bb:
+  %C = load i32* %B, align 16
+  br label %bb2
+
+bb1:
+  %D = load i32* %A, align 32
+  br label %bb2
+
+bb2:
+  %E = phi i32 [ %C, %bb ], [ %D, %bb1 ]
+  ret i32 %E
+; CHECK: @test10
+; CHECK:       bb2:
+; CHECK-NEXT:        phi i32* [ %B, %bb ], [ %A, %bb1 ]
+; CHECK-NEXT:   %E = load i32* %{{[^,]*}}, align 16
+; CHECK-NEXT:   ret i32 %E
+}
+
+
+; PR1777
+declare i1 @test11a()
+
+define i1 @test11() {
+entry:
+  %a = alloca i32
+  %i = ptrtoint i32* %a to i32
+  %b = call i1 @test11a()
+  br i1 %b, label %one, label %two
+
+one:
+  %x = phi i32 [%i, %entry], [%y, %two]
+  %c = call i1 @test11a()
+  br i1 %c, label %two, label %end
+
+two:
+  %y = phi i32 [%i, %entry], [%x, %one]
+  %d = call i1 @test11a()
+  br i1 %d, label %one, label %end
+
+end:
+  %f = phi i32 [ %x, %one], [%y, %two]
+  ; Change the %f to %i, and the optimizer suddenly becomes a lot smarter
+  ; even though %f must equal %i at this point
+  %g = inttoptr i32 %f to i32*
+  store i32 10, i32* %g
+  %z = call i1 @test11a()
+  ret i1 %z
+; CHECK: @test11
+; CHECK-NOT: phi i32
+; CHECK: ret i1 %z
+}