; RUN: opt < %s -rewrite-statepoints-for-gc -S 2>&1 | FileCheck %s ; RUN: opt < %s -passes=rewrite-statepoints-for-gc -S 2>&1 | FileCheck %s ; The rewriting needs to make %obj loop variant by inserting a phi ; of the original value and it's relocation. declare i64 addrspace(1)* @generate_obj() "gc-leaf-function" declare void @use_obj(i64 addrspace(1)*) "gc-leaf-function" define void @def_use_safepoint() gc "statepoint-example" { ; CHECK-LABEL: def_use_safepoint ; CHECK: phi i64 addrspace(1)* ; CHECK-DAG: [ %obj.relocated.casted, %loop ] ; CHECK-DAG: [ %obj, %entry ] entry: %obj = call i64 addrspace(1)* @generate_obj() br label %loop loop: ; preds = %loop, %entry call void @use_obj(i64 addrspace(1)* %obj) call void @do_safepoint() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ] br label %loop } declare void @do_safepoint() declare void @parse_point(i64 addrspace(1)*) define i64 addrspace(1)* @test1(i32 %caller, i8 addrspace(1)* %a, i8 addrspace(1)* %b, i32 %unknown) gc "statepoint-example" { ; CHECK-LABEL: test1 entry: br i1 undef, label %left, label %right left: ; preds = %entry ; CHECK: left: ; CHECK-NEXT: %a.cast = bitcast i8 addrspace(1)* %a to i64 addrspace(1)* ; CHECK-NEXT: [[CAST_L:%.*]] = bitcast i8 addrspace(1)* %a to i64 addrspace(1)* ; Our safepoint placement pass calls removeUnreachableBlocks, which does a bunch ; of simplifications to branch instructions. This bug is visible only when ; there are multiple branches into the same block from the same predecessor, and ; the following ceremony is to make that artefact survive a call to ; removeUnreachableBlocks. As an example, "br i1 undef, label %merge, label %merge" ; will get simplified to "br label %merge" by removeUnreachableBlocks. %a.cast = bitcast i8 addrspace(1)* %a to i64 addrspace(1)* switch i32 %unknown, label %right [ i32 0, label %merge i32 1, label %merge i32 5, label %merge i32 3, label %right ] right: ; preds = %left, %left, %entry ; CHECK: right: ; CHECK-NEXT: %b.cast = bitcast i8 addrspace(1)* %b to i64 addrspace(1)* ; CHECK-NEXT: [[CAST_R:%.*]] = bitcast i8 addrspace(1)* %b to i64 addrspace(1)* %b.cast = bitcast i8 addrspace(1)* %b to i64 addrspace(1)* br label %merge merge: ; preds = %right, %left, %left, %left ; CHECK: merge: ; CHECK-NEXT: %value.base = phi i64 addrspace(1)* [ [[CAST_L]], %left ], [ [[CAST_L]], %left ], [ [[CAST_L]], %left ], [ [[CAST_R]], %right ], !is_base_value !0 %value = phi i64 addrspace(1)* [ %a.cast, %left ], [ %a.cast, %left ], [ %a.cast, %left ], [ %b.cast, %right ] call void @parse_point(i64 addrspace(1)* %value) [ "deopt"(i32 0, i32 0, i32 0, i32 0, i32 0) ] ret i64 addrspace(1)* %value } ;; The purpose of this test is to ensure that when two live values share a ;; base defining value with inherent conflicts, we end up with a *single* ;; base phi/select per such node. This is testing an optimization, not a ;; fundemental correctness criteria define void @test2(i1 %cnd, i64 addrspace(1)* %base_obj, i64 addrspace(1)* %base_arg2) gc "statepoint-example" { ; CHECK-LABEL: @test2 entry: %obj = getelementptr i64, i64 addrspace(1)* %base_obj, i32 1 br label %loop ; CHECK-LABEL: loop ; CHECK: %current.base = phi i64 addrspace(1)* ; CHECK-DAG: [ %base_obj, %entry ] ; Given the two selects are equivelent, so are their base phis - ideally, ; we'd have commoned these, but that's a missed optimization, not correctness. ; CHECK-DAG: [ [[DISCARD:%.*.base.relocated.casted]], %loop ] ; CHECK-NOT: extra.base ; CHECK: next.base = select ; CHECK: next = select ; CHECK: extra2.base = select ; CHECK: extra2 = select ; CHECK: statepoint ;; Both 'next' and 'extra2' are live across the backedge safepoint... loop: ; preds = %loop, %entry %current = phi i64 addrspace(1)* [ %obj, %entry ], [ %next, %loop ] %extra = phi i64 addrspace(1)* [ %obj, %entry ], [ %extra2, %loop ] %nexta = getelementptr i64, i64 addrspace(1)* %current, i32 1 %next = select i1 %cnd, i64 addrspace(1)* %nexta, i64 addrspace(1)* %base_arg2 %extra2 = select i1 %cnd, i64 addrspace(1)* %nexta, i64 addrspace(1)* %base_arg2 call void @foo() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ] br label %loop } define i64 addrspace(1)* @test3(i1 %cnd, i64 addrspace(1)* %obj, i64 addrspace(1)* %obj2) gc "statepoint-example" { ; CHECK-LABEL: @test3 entry: br i1 %cnd, label %merge, label %taken taken: ; preds = %entry br label %merge merge: ; preds = %taken, %entry ; CHECK-LABEL: merge: ; CHECK-NEXT: phi ; CHECK-NEXT: phi ; CHECK-NEXT: gc.statepoint %bdv = phi i64 addrspace(1)* [ %obj, %entry ], [ %obj2, %taken ] call void @foo() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ] ret i64 addrspace(1)* %bdv } define i64 addrspace(1)* @test4(i1 %cnd, i64 addrspace(1)* %obj, i64 addrspace(1)* %obj2) gc "statepoint-example" { ; CHECK-LABEL: @test4 entry: br i1 %cnd, label %merge, label %taken taken: ; preds = %entry br label %merge merge: ; preds = %taken, %entry ; CHECK-LABEL: merge: ; CHECK-NEXT: phi ; CHECK-NEXT: gc.statepoint %bdv = phi i64 addrspace(1)* [ %obj, %entry ], [ %obj, %taken ] call void @foo() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ] ret i64 addrspace(1)* %bdv } define i64 addrspace(1)* @test5(i1 %cnd, i64 addrspace(1)* %obj, i64 addrspace(1)* %obj2) gc "statepoint-example" { ; CHECK-LABEL: @test5 entry: br label %merge merge: ; preds = %merge, %entry ; CHECK-LABEL: merge: ; CHECK-NEXT: phi ; CHECK-NEXT: phi ; CHECK-NEXT: br i1 %bdv = phi i64 addrspace(1)* [ %obj, %entry ], [ %obj2, %merge ] br i1 %cnd, label %merge, label %next next: ; preds = %merge call void @foo() [ "deopt"(i32 0, i32 -1, i32 0, i32 0, i32 0) ] ret i64 addrspace(1)* %bdv } declare void @foo()