92c55a315e
lifetime.start and lifetime.end are primarily intended for use on allocas, to enable stack coloring and other liveness optimizations. This is necessary because all (static) allocas are hoisted into the entry block, so lifetime markers are the only way to convey the actual lifetimes. However, lifetime.start and lifetime.end are currently *allowed* to be used on non-alloca pointers. We don't actually do this in practice, but just the mere fact that this is possible breaks the core purpose of the lifetime markers, which is stack coloring of allocas. Stack coloring can only work correctly if all lifetime markers for an alloca are analyzable. * If a lifetime marker may operate on multiple allocas via a select/phi, we don't know which lifetime actually starts/ends and handle it incorrectly (https://github.com/llvm/llvm-project/issues/104776). * Stack coloring operates on the assumption that all lifetime markers are visible, and not, for example, hidden behind a function call or escaped pointer. It's not possible to change this, as part of the purpose of lifetime markers is that they work even in the presence of escaped pointers, where simple use analysis is insufficient. I don't think there is any way to have coherent semantics for lifetime markers on allocas, while also permitting them on arbitrary pointer values. This PR restricts lifetimes to operate on allocas only. As a followup, I will also drop the size argument, which is superfluous if we always operate on an alloca. (This change also renders various code handling lifetime markers on non-alloca dead. I plan to clean up that kind of code after dropping the size argument as well.) In practice, I've only found a few places that currently produce lifetimes on non-allocas: * CoroEarly replaces the promise alloca with the result of an intrinsic, which will later be replaced back with an alloca. I think this is the only place where there is some legitimate loss of functionality, but I don't think this is particularly important (I don't think we'd expect the promise in a coroutine to admit useful lifetime optimization.) * SafeStack moves unsafe allocas onto a separate frame. We can safely drop lifetimes here, as SafeStack performs its own stack coloring. * Similar for AddressSanitizer, it also moves allocas into separate memory. * LSR sometimes replaces the lifetime argument with a GEP chain of the alloca (where the offsets ultimately cancel out). This is just unnecessary. (Fixed separately in https://github.com/llvm/llvm-project/pull/149492.) * InferAddrSpaces sometimes makes lifetimes operate on an addrspacecast of an alloca. I don't think this is necessary.
637 lines
17 KiB
LLVM
637 lines
17 KiB
LLVM
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
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; RUN: opt < %s -passes=dse -S | FileCheck %s
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target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
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declare void @use(ptr)
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; Tests where the pointer/object is accessible after the function returns.
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define void @accessible_after_return_1(ptr noalias %P, i1 %c1) {
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; CHECK-LABEL: @accessible_after_return_1(
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; CHECK-NEXT: br i1 [[C1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4
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; CHECK-NEXT: br label [[BB5:%.*]]
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; CHECK: bb2:
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; CHECK-NEXT: store i32 3, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb5:
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; CHECK-NEXT: call void @use(ptr [[P]])
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; CHECK-NEXT: ret void
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;
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store i32 1, ptr %P
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br i1 %c1, label %bb1, label %bb2
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bb1:
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store i32 0, ptr %P
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br label %bb5
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bb2:
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store i32 3, ptr %P
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br label %bb5
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bb5:
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call void @use(ptr %P)
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ret void
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}
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define void @accessible_after_return_2(ptr noalias %P, i1 %c.1, i1 %c.2) {
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; CHECK-LABEL: @accessible_after_return_2(
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; CHECK-NEXT: br i1 [[C_1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4
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; CHECK-NEXT: br label [[BB5:%.*]]
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; CHECK: bb2:
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; CHECK-NEXT: br i1 [[C_2:%.*]], label [[BB3:%.*]], label [[BB4:%.*]]
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; CHECK: bb3:
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; CHECK-NEXT: store i32 3, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb4:
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; CHECK-NEXT: store i32 5, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb5:
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; CHECK-NEXT: call void @use(ptr [[P]])
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; CHECK-NEXT: ret void
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;
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store i32 1, ptr %P
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br i1 %c.1, label %bb1, label %bb2
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bb1:
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store i32 0, ptr %P
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br label %bb5
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bb2:
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br i1 %c.2, label %bb3, label %bb4
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bb3:
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store i32 3, ptr %P
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br label %bb5
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bb4:
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store i32 5, ptr %P
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br label %bb5
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bb5:
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call void @use(ptr %P)
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ret void
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}
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; Cannot remove store in entry block because it is not overwritten on path
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; entry->bb2->bb5.
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define void @accessible_after_return_3(ptr noalias %P, i1 %c1) {
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; CHECK-LABEL: @accessible_after_return_3(
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; CHECK-NEXT: store i32 1, ptr [[P:%.*]], align 4
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; CHECK-NEXT: br i1 [[C1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: store i32 0, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5:%.*]]
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; CHECK: bb2:
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb5:
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; CHECK-NEXT: call void @use(ptr [[P]])
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; CHECK-NEXT: ret void
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;
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store i32 1, ptr %P
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br i1 %c1, label %bb1, label %bb2
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bb1:
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store i32 0, ptr %P
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br label %bb5
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bb2:
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br label %bb5
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bb5:
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call void @use(ptr %P)
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ret void
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}
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; Cannot remove store in entry block because it is not overwritten on path
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; entry->bb2->bb5.
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define void @accessible_after_return_4(ptr noalias %P, i1 %c1) {
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; CHECK-LABEL: @accessible_after_return_4(
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; CHECK-NEXT: store i32 1, ptr [[P:%.*]], align 4
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; CHECK-NEXT: br i1 [[C1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: store i32 0, ptr [[P]], align 4
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; CHECK-NEXT: call void @use(ptr [[P]])
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; CHECK-NEXT: br label [[BB5:%.*]]
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; CHECK: bb2:
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb5:
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; CHECK-NEXT: ret void
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;
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store i32 1, ptr %P
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br i1 %c1, label %bb1, label %bb2
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bb1:
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store i32 0, ptr %P
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call void @use(ptr %P)
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br label %bb5
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bb2:
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br label %bb5
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bb5:
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ret void
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}
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; Cannot remove the store in entry, as it is not overwritten on all paths to an
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; exit (patch including bb4).
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define void @accessible_after_return5(ptr %P, i1 %c.1, i1 %c.2) {
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; CHECK-LABEL: @accessible_after_return5(
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; CHECK-NEXT: entry:
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; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4
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; CHECK-NEXT: br i1 [[C_1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: br i1 [[C_2:%.*]], label [[BB3:%.*]], label [[BB4:%.*]]
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; CHECK: bb2:
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; CHECK-NEXT: store i32 1, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5:%.*]]
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; CHECK: bb3:
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; CHECK-NEXT: store i32 2, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb4:
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb5:
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; CHECK-NEXT: ret void
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;
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entry:
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store i32 0, ptr %P
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br i1 %c.1, label %bb1, label %bb2
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bb1:
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br i1 %c.2, label %bb3, label %bb4
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bb2:
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store i32 1, ptr %P
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br label %bb5
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bb3:
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store i32 2, ptr %P
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br label %bb5
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bb4:
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br label %bb5
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bb5:
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ret void
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}
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; Can remove store in entry block, because it is overwritten before each return.
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define void @accessible_after_return6(ptr %P, i1 %c.1, i1 %c.2) {
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; CHECK-LABEL: @accessible_after_return6(
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; CHECK-NEXT: entry:
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; CHECK-NEXT: br i1 [[C_1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: br i1 [[C_2:%.*]], label [[BB3:%.*]], label [[BB4:%.*]]
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; CHECK: bb2:
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; CHECK-NEXT: store i32 1, ptr [[P:%.*]], align 4
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; CHECK-NEXT: ret void
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; CHECK: bb3:
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; CHECK-NEXT: store i32 2, ptr [[P]], align 4
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; CHECK-NEXT: ret void
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; CHECK: bb4:
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; CHECK-NEXT: store i32 3, ptr [[P]], align 4
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; CHECK-NEXT: ret void
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;
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entry:
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store i32 0, ptr %P
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br i1 %c.1, label %bb1, label %bb2
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bb1:
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br i1 %c.2, label %bb3, label %bb4
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bb2:
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store i32 1, ptr %P
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ret void
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bb3:
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store i32 2, ptr %P
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ret void
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bb4:
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store i32 3, ptr %P
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ret void
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}
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; Can remove store in bb1, because it is overwritten along each path
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; from bb1 to the exit.
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define void @accessible_after_return7(ptr %P, i1 %c.1, i1 %c.2) {
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; CHECK-LABEL: @accessible_after_return7(
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; CHECK-NEXT: entry:
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; CHECK-NEXT: br i1 [[C_1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: br i1 [[C_2:%.*]], label [[BB3:%.*]], label [[BB4:%.*]]
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; CHECK: bb3:
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; CHECK-NEXT: store i32 2, ptr [[P:%.*]], align 4
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; CHECK-NEXT: br label [[BB5:%.*]]
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; CHECK: bb4:
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; CHECK-NEXT: store i32 1, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb2:
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb5:
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; CHECK-NEXT: ret void
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;
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entry:
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br i1 %c.1, label %bb1, label %bb2
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bb1:
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store i32 0, ptr %P
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br i1 %c.2, label %bb3, label %bb4
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bb3:
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store i32 2, ptr %P
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br label %bb5
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bb4:
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store i32 1, ptr %P
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br label %bb5
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bb2:
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br label %bb5
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bb5:
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ret void
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}
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; Cannot remove store in entry block, because it is overwritten along each path to
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; the exit (entry->bb1->bb4->bb5).
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define void @accessible_after_return8(ptr %P, i1 %c.1, i1 %c.2) {
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; CHECK-LABEL: @accessible_after_return8(
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; CHECK-NEXT: entry:
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; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4
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; CHECK-NEXT: br i1 [[C_1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: br i1 [[C_2:%.*]], label [[BB3:%.*]], label [[BB4:%.*]]
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; CHECK: bb2:
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; CHECK-NEXT: store i32 1, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5:%.*]]
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; CHECK: bb3:
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; CHECK-NEXT: store i32 2, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb4:
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; CHECK-NEXT: br label [[BB5]]
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; CHECK: bb5:
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; CHECK-NEXT: ret void
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;
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entry:
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store i32 0, ptr %P
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br i1 %c.1, label %bb1, label %bb2
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bb1:
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br i1 %c.2, label %bb3, label %bb4
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bb2:
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store i32 1, ptr %P
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br label %bb5
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bb3:
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store i32 2, ptr %P
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br label %bb5
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bb4:
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br label %bb5
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bb5:
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ret void
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}
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; Make sure no stores are removed here. In particular, the store in if.then
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; should not be removed.
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define void @accessible_after_return9(ptr noalias %ptr) {
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; CHECK-LABEL: @accessible_after_return9(
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; CHECK-NEXT: entry:
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; CHECK-NEXT: [[C_0:%.*]] = call i1 @cond()
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; CHECK-NEXT: br i1 [[C_0]], label [[FOR_BODY:%.*]], label [[FOR_END:%.*]]
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; CHECK: for.body:
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; CHECK-NEXT: store i8 99, ptr [[PTR:%.*]], align 8
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; CHECK-NEXT: [[C_1:%.*]] = call i1 @cond()
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; CHECK-NEXT: br i1 [[C_1]], label [[IF_END:%.*]], label [[IF_THEN:%.*]]
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; CHECK: if.then:
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; CHECK-NEXT: store i8 20, ptr [[PTR]], align 8
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; CHECK-NEXT: br label [[IF_END]]
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; CHECK: if.end:
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; CHECK-NEXT: [[C_2:%.*]] = call i1 @cond()
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; CHECK-NEXT: br i1 [[C_2]], label [[IF_THEN10:%.*]], label [[FOR_INC:%.*]]
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; CHECK: if.then10:
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; CHECK-NEXT: store i8 0, ptr [[PTR]], align 8
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; CHECK-NEXT: br label [[FOR_INC]]
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; CHECK: for.inc:
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; CHECK-NEXT: [[C_3:%.*]] = call i1 @cond()
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; CHECK-NEXT: br i1 [[C_3]], label [[FOR_BODY]], label [[FOR_END]]
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; CHECK: for.end:
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; CHECK-NEXT: ret void
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;
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entry:
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%c.0 = call i1 @cond()
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br i1 %c.0, label %for.body, label %for.end
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for.body:
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store i8 99, ptr %ptr, align 8
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%c.1 = call i1 @cond()
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br i1 %c.1, label %if.end, label %if.then
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if.then:
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store i8 20, ptr %ptr, align 8
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br label %if.end
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if.end:
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%c.2 = call i1 @cond()
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br i1 %c.2, label %if.then10, label %for.inc
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if.then10:
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store i8 0, ptr %ptr, align 8
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br label %for.inc
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for.inc:
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%c.3 = call i1 @cond()
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br i1 %c.3, label %for.body, label %for.end
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for.end:
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ret void
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}
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; Cannot remove store in entry block because it is not overwritten on path
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; entry->bb2->bb4. Also make sure we deal with dead exit blocks without
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; crashing.
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define void @accessible_after_return10_dead_block(ptr %P, i1 %c.1, i1 %c.2) {
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; CHECK-LABEL: @accessible_after_return10_dead_block(
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; CHECK-NEXT: entry:
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; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4
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; CHECK-NEXT: br i1 [[C_1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: br i1 [[C_2:%.*]], label [[BB3:%.*]], label [[BB4:%.*]]
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; CHECK: bb2:
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; CHECK-NEXT: store i32 1, ptr [[P]], align 4
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; CHECK-NEXT: ret void
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; CHECK: bb3:
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; CHECK-NEXT: store i32 2, ptr [[P]], align 4
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; CHECK-NEXT: ret void
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; CHECK: bb4:
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; CHECK-NEXT: ret void
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; CHECK: bb5:
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; CHECK-NEXT: ret void
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;
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entry:
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store i32 0, ptr %P
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br i1 %c.1, label %bb1, label %bb2
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bb1:
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br i1 %c.2, label %bb3, label %bb4
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bb2:
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store i32 1, ptr %P
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ret void
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bb3:
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store i32 2, ptr %P
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ret void
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bb4:
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ret void
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bb5:
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ret void
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}
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@linenum = external local_unnamed_addr global i32, align 4
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define void @accessible_after_return11_loop(ptr noalias %p) {
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; CHECK-LABEL: @accessible_after_return11_loop(
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; CHECK-NEXT: entry:
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; CHECK-NEXT: br label [[FOR_BODY_I:%.*]]
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; CHECK: for.body.i:
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; CHECK-NEXT: [[C_1:%.*]] = call i1 @cond()
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; CHECK-NEXT: br i1 [[C_1]], label [[FOR_BODY_I]], label [[INIT_PARSE_EXIT:%.*]]
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; CHECK: init_parse.exit:
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; CHECK-NEXT: store i32 1, ptr [[P:%.*]], align 4
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; CHECK-NEXT: store i32 0, ptr @linenum, align 4
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; CHECK-NEXT: br label [[FOR_BODY_I20:%.*]]
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; CHECK: for.body.i20:
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; CHECK-NEXT: [[C_2:%.*]] = call i1 @cond()
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; CHECK-NEXT: br i1 [[C_2]], label [[FOR_BODY_I20]], label [[EXIT:%.*]]
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; CHECK: exit:
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; CHECK-NEXT: ret void
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;
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entry:
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br label %for.body.i
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for.body.i: ; preds = %for.body.i, %entry
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%c.1 = call i1 @cond()
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br i1 %c.1, label %for.body.i, label %init_parse.exit
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init_parse.exit: ; preds = %for.body.i
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store i32 0, ptr @linenum, align 4
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store i32 1, ptr %p
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store i32 0, ptr @linenum, align 4
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br label %for.body.i20
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for.body.i20: ; preds = %for.body.i20, %init_parse.exit
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%c.2 = call i1 @cond()
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br i1 %c.2, label %for.body.i20, label %exit
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exit:
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ret void
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}
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declare i1 @cond() readnone nounwind
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; Tests where the pointer/object is *NOT* accessible after the function returns.
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; The store in the entry block can be eliminated, because it is overwritten
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; on all paths to the exit.
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define void @alloca_1(i1 %c1) {
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; CHECK-LABEL: @alloca_1(
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; CHECK-NEXT: [[P:%.*]] = alloca i32, align 4
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; CHECK-NEXT: br i1 [[C1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
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; CHECK: bb1:
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; CHECK-NEXT: store i32 0, ptr [[P]], align 4
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; CHECK-NEXT: br label [[BB5:%.*]]
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; CHECK: bb2:
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; CHECK-NEXT: store i32 3, ptr [[P]], align 4
|
|
; CHECK-NEXT: br label [[BB5]]
|
|
; CHECK: bb5:
|
|
; CHECK-NEXT: call void @use(ptr [[P]])
|
|
; CHECK-NEXT: ret void
|
|
;
|
|
%P = alloca i32
|
|
store i32 1, ptr %P
|
|
br i1 %c1, label %bb1, label %bb2
|
|
|
|
bb1:
|
|
store i32 0, ptr %P
|
|
br label %bb5
|
|
bb2:
|
|
store i32 3, ptr %P
|
|
br label %bb5
|
|
|
|
bb5:
|
|
call void @use(ptr %P)
|
|
ret void
|
|
}
|
|
|
|
; The store in the entry block can be eliminated, because it is overwritten
|
|
; on all paths to the exit.
|
|
define void @alloca_2(i1 %c.1, i1 %c.2) {
|
|
; CHECK-LABEL: @alloca_2(
|
|
; CHECK-NEXT: [[P:%.*]] = alloca i32, align 4
|
|
; CHECK-NEXT: br i1 [[C_1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
|
|
; CHECK: bb1:
|
|
; CHECK-NEXT: store i32 0, ptr [[P]], align 4
|
|
; CHECK-NEXT: br label [[BB5:%.*]]
|
|
; CHECK: bb2:
|
|
; CHECK-NEXT: br i1 [[C_2:%.*]], label [[BB3:%.*]], label [[BB4:%.*]]
|
|
; CHECK: bb3:
|
|
; CHECK-NEXT: store i32 3, ptr [[P]], align 4
|
|
; CHECK-NEXT: br label [[BB5]]
|
|
; CHECK: bb4:
|
|
; CHECK-NEXT: store i32 5, ptr [[P]], align 4
|
|
; CHECK-NEXT: br label [[BB5]]
|
|
; CHECK: bb5:
|
|
; CHECK-NEXT: call void @use(ptr [[P]])
|
|
; CHECK-NEXT: ret void
|
|
;
|
|
%P = alloca i32
|
|
store i32 1, ptr %P
|
|
br i1 %c.1, label %bb1, label %bb2
|
|
|
|
bb1:
|
|
store i32 0, ptr %P
|
|
br label %bb5
|
|
|
|
bb2:
|
|
br i1 %c.2, label %bb3, label %bb4
|
|
|
|
bb3:
|
|
store i32 3, ptr %P
|
|
br label %bb5
|
|
|
|
bb4:
|
|
store i32 5, ptr %P
|
|
br label %bb5
|
|
|
|
bb5:
|
|
call void @use(ptr %P)
|
|
ret void
|
|
}
|
|
|
|
; The store in the entry block cannot be eliminated. There's a path from the
|
|
; first store to the read in bb5, where the location is not overwritten.
|
|
define void @alloca_3(i1 %c1) {
|
|
; CHECK-LABEL: @alloca_3(
|
|
; CHECK-NEXT: [[P:%.*]] = alloca i32, align 4
|
|
; CHECK-NEXT: store i32 1, ptr [[P]], align 4
|
|
; CHECK-NEXT: br i1 [[C1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
|
|
; CHECK: bb1:
|
|
; CHECK-NEXT: store i32 0, ptr [[P]], align 4
|
|
; CHECK-NEXT: br label [[BB5:%.*]]
|
|
; CHECK: bb2:
|
|
; CHECK-NEXT: br label [[BB5]]
|
|
; CHECK: bb5:
|
|
; CHECK-NEXT: call void @use(ptr [[P]])
|
|
; CHECK-NEXT: ret void
|
|
;
|
|
%P = alloca i32
|
|
store i32 1, ptr %P
|
|
br i1 %c1, label %bb1, label %bb2
|
|
|
|
bb1:
|
|
store i32 0, ptr %P
|
|
br label %bb5
|
|
bb2:
|
|
br label %bb5
|
|
|
|
bb5:
|
|
call void @use(ptr %P)
|
|
ret void
|
|
}
|
|
|
|
; The store in the entry block can be eliminated, because it is overwritten
|
|
; before the use in bb1 and not read on other paths to the function exit. The
|
|
; object cannot be accessed by the caller.
|
|
define void @alloca_4(i1 %c1) {
|
|
; CHECK-LABEL: @alloca_4(
|
|
; CHECK-NEXT: [[P:%.*]] = alloca i32, align 4
|
|
; CHECK-NEXT: br i1 [[C1:%.*]], label [[BB1:%.*]], label [[BB2:%.*]]
|
|
; CHECK: bb1:
|
|
; CHECK-NEXT: store i32 0, ptr [[P]], align 4
|
|
; CHECK-NEXT: call void @use(ptr [[P]])
|
|
; CHECK-NEXT: br label [[BB5:%.*]]
|
|
; CHECK: bb2:
|
|
; CHECK-NEXT: br label [[BB5]]
|
|
; CHECK: bb5:
|
|
; CHECK-NEXT: ret void
|
|
;
|
|
%P = alloca i32
|
|
store i32 1, ptr %P
|
|
br i1 %c1, label %bb1, label %bb2
|
|
|
|
bb1:
|
|
store i32 0, ptr %P
|
|
call void @use(ptr %P)
|
|
br label %bb5
|
|
|
|
bb2:
|
|
br label %bb5
|
|
|
|
bb5:
|
|
ret void
|
|
}
|
|
|
|
%struct.blam.4 = type { %struct.bar.5, [4 x i8] }
|
|
%struct.bar.5 = type <{ i64, ptr, i32, i64 }>
|
|
|
|
; Make sure we do not eliminate the store in %bb.
|
|
define void @alloca_5(i1 %c) {
|
|
; CHECK-LABEL: @alloca_5(
|
|
; CHECK-NEXT: bb:
|
|
; CHECK-NEXT: [[TMP:%.*]] = alloca [[STRUCT_BLAM_4:%.*]], align 8
|
|
; CHECK-NEXT: [[TMP38:%.*]] = getelementptr inbounds [[STRUCT_BLAM_4]], ptr [[TMP]], i64 0, i32 0, i32 3
|
|
; CHECK-NEXT: store i64 0, ptr [[TMP38]], align 4
|
|
; CHECK-NEXT: br i1 [[C:%.*]], label [[BB46:%.*]], label [[BB47:%.*]]
|
|
; CHECK: bb46:
|
|
; CHECK-NEXT: ret void
|
|
; CHECK: bb47:
|
|
; CHECK-NEXT: [[TMP48:%.*]] = getelementptr inbounds [[STRUCT_BLAM_4]], ptr [[TMP]], i64 0, i32 0, i32 2
|
|
; CHECK-NEXT: store i32 20, ptr [[TMP48]], align 8
|
|
; CHECK-NEXT: br label [[BB52:%.*]]
|
|
; CHECK: bb52:
|
|
; CHECK-NEXT: br i1 [[C]], label [[BB68:%.*]], label [[BB59:%.*]]
|
|
; CHECK: bb59:
|
|
; CHECK-NEXT: call void @use.2(ptr [[TMP]])
|
|
; CHECK-NEXT: ret void
|
|
; CHECK: bb68:
|
|
; CHECK-NEXT: ret void
|
|
;
|
|
bb:
|
|
%tmp = alloca %struct.blam.4, align 8
|
|
%tmp36 = getelementptr inbounds %struct.blam.4, ptr %tmp, i64 0, i32 0, i32 1
|
|
%tmp38 = getelementptr inbounds %struct.blam.4, ptr %tmp, i64 0, i32 0, i32 3
|
|
store i64 0, ptr %tmp38, align 4
|
|
br i1 %c, label %bb46, label %bb47
|
|
|
|
bb46: ; preds = %bb12
|
|
call void @llvm.memset.p0.i64(ptr nonnull align 8 dereferenceable(20) %tmp36, i8 0, i64 26, i1 false)
|
|
ret void
|
|
|
|
bb47: ; preds = %bb12
|
|
%tmp48 = getelementptr inbounds %struct.blam.4, ptr %tmp, i64 0, i32 0, i32 2
|
|
store i32 20, ptr %tmp48, align 8
|
|
br label %bb52
|
|
|
|
bb52: ; preds = %bb47
|
|
br i1 %c, label %bb68, label %bb59
|
|
|
|
bb59: ; preds = %bb52
|
|
call void @use.2(ptr %tmp)
|
|
ret void
|
|
|
|
bb68: ; preds = %bb52
|
|
ret void
|
|
}
|
|
|
|
declare void @use.2(ptr)
|
|
|
|
declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg)
|