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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -passes=hotcoldsplit -hotcoldsplit-threshold=0 < %s 2>&1 | FileCheck %s
declare void @llvm.lifetime.start.p0(i64, ptr nocapture)
declare void @llvm.lifetime.end.p0(i64, ptr nocapture)
declare void @cold_use(ptr) cold
declare void @use(ptr)
; In this CFG, splitting will extract the blocks extract{1,2}. I.e., it will
; extract a lifetime.start marker, but not the corresponding lifetime.end
; marker. Make sure that a lifetime.start marker is emitted before the call to
; the split function, and *only* that marker.
;
; entry
; / \
; extract1 no-extract1
; (lt.start) |
; / |
; extract2 |
; \_____ |
; \ /
; exit
; (lt.end)
;
; After splitting, we should see:
;
; entry
; / \
; codeRepl no-extract1
; (lt.start) |
; \ /
; exit
; (lt.end)
define void @only_lifetime_start_is_cold() {
; CHECK-LABEL: @only_lifetime_start_is_cold(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOCAL1:%.*]] = alloca i256
; CHECK-NEXT: br i1 undef, label [[CODEREPL:%.*]], label [[NO_EXTRACT1:%.*]]
; CHECK: codeRepl:
; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 -1, ptr [[LOCAL1]])
; CHECK-NEXT: [[TARGETBLOCK:%.*]] = call i1 @only_lifetime_start_is_cold.cold.1(ptr [[LOCAL1]]) #3
; CHECK-NEXT: br i1 [[TARGETBLOCK]], label [[NO_EXTRACT1]], label [[EXIT:%.*]]
; CHECK: no-extract1:
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 1, ptr [[LOCAL1]])
; CHECK-NEXT: ret void
;
entry:
%local1 = alloca i256
br i1 undef, label %extract1, label %no-extract1
extract1:
; lt.start
call void @llvm.lifetime.start.p0(i64 1, ptr %local1)
call void @cold_use(ptr %local1)
br i1 undef, label %extract2, label %no-extract1
extract2:
br label %exit
no-extract1:
br label %exit
exit:
; lt.end
call void @llvm.lifetime.end.p0(i64 1, ptr %local1)
ret void
}
; In this CFG, splitting will extract the block extract1. I.e., it will extract
; a lifetime.end marker, but not the corresponding lifetime.start marker. Do
; not emit a lifetime.end marker after the call to the split function.
;
; entry
; (lt.start)
; / \
; no-extract1 extract1
; (lt.end) (lt.end)
; \ /
; exit
;
; After splitting, we should see:
;
; entry
; (lt.start)
; / \
; no-extract1 codeRepl
; (lt.end)
; \ /
; exit
define void @only_lifetime_end_is_cold() {
; CHECK-LABEL: @only_lifetime_end_is_cold(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOCAL1:%.*]] = alloca i256
; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 1, ptr [[LOCAL1]])
; CHECK-NEXT: br i1 undef, label [[NO_EXTRACT1:%.*]], label [[CODEREPL:%.*]]
; CHECK: no-extract1:
; CHECK-NEXT: call void @llvm.lifetime.end.p0(i64 1, ptr [[LOCAL1]])
; CHECK-NEXT: br label [[EXIT:%.*]]
; CHECK: codeRepl:
; CHECK-NEXT: call void @only_lifetime_end_is_cold.cold.1(ptr [[LOCAL1]]) #3
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
; lt.start
%local1 = alloca i256
call void @llvm.lifetime.start.p0(i64 1, ptr %local1)
br i1 undef, label %no-extract1, label %extract1
no-extract1:
; lt.end
call void @llvm.lifetime.end.p0(i64 1, ptr %local1)
br label %exit
extract1:
; lt.end
call void @cold_use(ptr %local1)
call void @llvm.lifetime.end.p0(i64 1, ptr %local1)
br label %exit
exit:
ret void
}
; In this CFG, splitting will extract the blocks extract{1,2,3}. Lifting the
; lifetime.end marker would be a miscompile.
define void @do_not_lift_lifetime_end() {
; CHECK-LABEL: @do_not_lift_lifetime_end(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[LOCAL1:%.*]] = alloca i256
; CHECK-NEXT: call void @llvm.lifetime.start.p0(i64 1, ptr [[LOCAL1]])
; CHECK-NEXT: br label [[HEADER:%.*]]
; CHECK: header:
; CHECK-NEXT: call void @use(ptr [[LOCAL1]])
; CHECK-NEXT: br i1 undef, label [[EXIT:%.*]], label [[CODEREPL:%.*]]
; CHECK: codeRepl:
; CHECK-NEXT: [[TARGETBLOCK:%.*]] = call i1 @do_not_lift_lifetime_end.cold.1(ptr [[LOCAL1]]) #3
; CHECK-NEXT: br i1 [[TARGETBLOCK]], label [[HEADER]], label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
; lt.start
%local1 = alloca i256
call void @llvm.lifetime.start.p0(i64 1, ptr %local1)
br label %header
header:
; If the lifetime.end marker is lifted, this use becomes dead the second time
; the header block is executed.
call void @use(ptr %local1)
br i1 undef, label %exit, label %extract1
extract1:
call void @cold_use(ptr %local1)
br i1 undef, label %extract2, label %extract3
extract2:
; Backedge.
br label %header
extract3:
; lt.end
call void @llvm.lifetime.end.p0(i64 1, ptr %local1)
br label %exit
exit:
ret void
}
|
