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      1 ; RUN: opt %s -rewrite-statepoints-for-gc -S 2>&1 | FileCheck %s
      2 
      3 declare i64 addrspace(1)* @generate_obj()
      4 declare void @use_obj(i64 addrspace(1)*)
      5 
      6 ; The rewriting needs to make %obj loop variant by inserting a phi 
      7 ; of the original value and it's relocation.
      8 define void @def_use_safepoint() gc "statepoint-example" {
      9 ; CHECK-LABEL: def_use_safepoint
     10 entry:
     11   %obj = call i64 addrspace(1)* @generate_obj()
     12   br label %loop
     13 
     14 loop:
     15 ; CHECK: phi i64 addrspace(1)* 
     16 ; CHECK-DAG: [ %obj.relocated.casted, %loop ]
     17 ; CHECK-DAG: [ %obj, %entry ]
     18   call void @use_obj(i64 addrspace(1)* %obj)
     19   %safepoint_token = call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* @do_safepoint, i32 0, i32 0, i32 0, i32 5, i32 0, i32 -1, i32 0, i32 0, i32 0)
     20   br label %loop
     21 }
     22 
     23 declare void @do_safepoint()
     24 
     25 declare void @parse_point(i64 addrspace(1)*)
     26 
     27 define i64 addrspace(1)* @test1(i32 %caller, i8 addrspace(1)* %a, i8 addrspace(1)* %b, i32 %unknown) gc "statepoint-example" {
     28 ; CHECK-LABEL: test1
     29  entry:
     30   br i1 undef, label %left, label %right
     31 
     32  left:
     33   %a.cast = bitcast i8 addrspace(1)* %a to i64 addrspace(1)*
     34 ; CHECK: left:
     35 ; CHECK-NEXT: %a.cast = bitcast i8 addrspace(1)* %a to i64 addrspace(1)*
     36 ; CHECK-NEXT: [[CAST_L:%.*]] = bitcast i8 addrspace(1)* %a to i64 addrspace(1)*
     37 
     38 ; Our safepoint placement pass calls removeUnreachableBlocks, which does a bunch
     39 ; of simplifications to branch instructions.  This bug is visible only when
     40 ; there are multiple branches into the same block from the same predecessor, and
     41 ; the following ceremony is to make that artefact survive a call to 
     42 ; removeUnreachableBlocks.  As an example, "br i1 undef, label %merge, label %merge"
     43 ; will get simplified to "br label %merge" by removeUnreachableBlocks.
     44   switch i32 %unknown, label %right [ i32 0, label %merge
     45                                       i32 1, label %merge
     46                                       i32 5, label %merge
     47                                       i32 3, label %right ]
     48 
     49  right:
     50   %b.cast = bitcast i8 addrspace(1)* %b to i64 addrspace(1)*
     51   br label %merge
     52 ; CHECK: right:
     53 ; CHECK-NEXT: %b.cast = bitcast i8 addrspace(1)* %b to i64 addrspace(1)*
     54 ; CHECK-NEXT: [[CAST_R:%.*]] = bitcast i8 addrspace(1)* %b to i64 addrspace(1)*
     55 
     56  merge:
     57 ; CHECK: merge:
     58 ; CHECK-NEXT: %value.base = phi i64 addrspace(1)* [ [[CAST_L]], %left ], [ [[CAST_L]], %left ], [ [[CAST_L]], %left ], [ [[CAST_R]], %right ], !is_base_value !0
     59   %value = phi i64 addrspace(1)* [ %a.cast, %left], [ %a.cast, %left], [ %a.cast, %left], [ %b.cast, %right]
     60   %safepoint_token = call i32 (i64, i32, void (i64 addrspace(1)*)*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidp1i64f(i64 0, i32 0, void (i64 addrspace(1)*)* @parse_point, i32 1, i32 0, i64 addrspace(1)* %value, i32 0, i32 5, i32 0, i32 0, i32 0, i32 0, i32 0)
     61 
     62   ret i64 addrspace(1)* %value
     63 }
     64 
     65 ;; The purpose of this test is to ensure that when two live values share a
     66 ;;  base defining value with inherent conflicts, we end up with a *single*
     67 ;;  base phi/select per such node.  This is testing an optimization, not a
     68 ;;  fundemental correctness criteria
     69 define void @test2(i1 %cnd, i64 addrspace(1)* %base_obj, i64 addrspace(1)* %base_arg2)  gc "statepoint-example" {
     70 ; CHECK-LABEL: @test2
     71 entry:
     72   %obj = getelementptr i64, i64 addrspace(1)* %base_obj, i32 1
     73   br label %loop
     74 
     75 loop:                                             ; preds = %loop, %entry
     76 ; CHECK-LABEL: loop
     77 ; CHECK:   %current.base = phi i64 addrspace(1)*
     78 ; CHECK-DAG: [ %base_obj, %entry ]
     79 ; Given the two selects are equivelent, so are their base phis - ideally,
     80 ; we'd have commoned these, but that's a missed optimization, not correctness.
     81 ; CHECK-DAG: [ [[DISCARD:%.*.base.relocated.casted]], %loop ]
     82 ; CHECK-NOT: extra.base
     83 ; CHECK: next = select
     84 ; CHECK: extra2.base = select
     85 ; CHECK: extra2 = select
     86 ; CHECK: statepoint
     87 ;; Both 'next' and 'extra2' are live across the backedge safepoint...
     88   %current = phi i64 addrspace(1)* [ %obj, %entry ], [ %next, %loop ]
     89   %extra = phi i64 addrspace(1)* [ %obj, %entry ], [ %extra2, %loop ]
     90   %nexta = getelementptr i64, i64 addrspace(1)* %current, i32 1
     91   %next = select i1 %cnd, i64 addrspace(1)* %nexta, i64 addrspace(1)* %base_arg2
     92   %extra2 = select i1 %cnd, i64 addrspace(1)* %nexta, i64 addrspace(1)* %base_arg2
     93   %safepoint_token = call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* @foo, i32 0, i32 0, i32 0, i32 5, i32 0, i32 -1, i32 0, i32 0, i32 0)
     94   br label %loop
     95 }
     96 
     97 define i64 addrspace(1)* @test3(i1 %cnd, i64 addrspace(1)* %obj, 
     98                                 i64 addrspace(1)* %obj2)
     99     gc "statepoint-example" {
    100 ; CHECK-LABEL: @test3
    101 entry:
    102   br i1 %cnd, label %merge, label %taken
    103 taken:
    104   br label %merge
    105 merge:
    106 ; CHECK-LABEL: merge:
    107 ; CHECK-NEXT: %bdv = phi
    108 ; CHECK-NEXT: gc.statepoint
    109   %bdv = phi i64 addrspace(1)* [ %obj, %entry ], [ %obj2, %taken ]
    110   %safepoint_token = call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* @foo, i32 0, i32 0, i32 0, i32 5, i32 0, i32 -1, i32 0, i32 0, i32 0)
    111   ret i64 addrspace(1)* %bdv
    112 }
    113 
    114 define i64 addrspace(1)* @test4(i1 %cnd, i64 addrspace(1)* %obj, 
    115                                 i64 addrspace(1)* %obj2)
    116     gc "statepoint-example" {
    117 ; CHECK-LABEL: @test4
    118 entry:
    119   br i1 %cnd, label %merge, label %taken
    120 taken:
    121   br label %merge
    122 merge:
    123 ; CHECK-LABEL: merge:
    124 ; CHECK-NEXT: %bdv = phi
    125 ; CHECK-NEXT: gc.statepoint
    126   %bdv = phi i64 addrspace(1)* [ %obj, %entry ], [ %obj, %taken ]
    127   %safepoint_token = call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* @foo, i32 0, i32 0, i32 0, i32 5, i32 0, i32 -1, i32 0, i32 0, i32 0)
    128   ret i64 addrspace(1)* %bdv
    129 }
    130 
    131 define i64 addrspace(1)* @test5(i1 %cnd, i64 addrspace(1)* %obj, 
    132                                 i64 addrspace(1)* %obj2)
    133     gc "statepoint-example" {
    134 ; CHECK-LABEL: @test5
    135 entry:
    136   br label %merge
    137 merge:
    138 ; CHECK-LABEL: merge:
    139 ; CHECK-NEXT: %bdv = phi
    140 ; CHECK-NEXT: br i1
    141   %bdv = phi i64 addrspace(1)* [ %obj, %entry ], [ %obj2, %merge ]
    142   br i1 %cnd, label %merge, label %next
    143 next:
    144   %safepoint_token = call i32 (i64, i32, void ()*, i32, i32, ...) @llvm.experimental.gc.statepoint.p0f_isVoidf(i64 0, i32 0, void ()* @foo, i32 0, i32 0, i32 0, i32 5, i32 0, i32 -1, i32 0, i32 0, i32 0)
    145   ret i64 addrspace(1)* %bdv
    146 }
    147 
    148 
    149 declare void @foo()
    150 declare i32 @llvm.experimental.gc.statepoint.p0f_isVoidf(i64, i32, void ()*, i32, i32, ...)
    151 declare i32 @llvm.experimental.gc.statepoint.p0f_isVoidp1i64f(i64, i32, void (i64 addrspace(1)*)*, i32, i32, ...)
    152