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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=instcombine -S < %s | FileCheck %s
;; This tests that the instructions in the entry blocks are sunk into each
;; arm of the 'if'.
define i32 @test1(i1 %C, i32 %A, i32 %B) {
; CHECK-LABEL: @test1(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[C:%.*]], label [[THEN:%.*]], label [[ENDIF:%.*]]
; CHECK: then:
; CHECK-NEXT: [[TMP_9:%.*]] = add i32 [[B:%.*]], [[A:%.*]]
; CHECK-NEXT: ret i32 [[TMP_9]]
; CHECK: endif:
; CHECK-NEXT: [[TMP_2:%.*]] = sdiv i32 [[A]], [[B]]
; CHECK-NEXT: ret i32 [[TMP_2]]
;
entry:
%tmp.2 = sdiv i32 %A, %B ; <i32> [#uses=1]
%tmp.9 = add i32 %B, %A ; <i32> [#uses=1]
br i1 %C, label %then, label %endif
then: ; preds = %entry
ret i32 %tmp.9
endif: ; preds = %entry
ret i32 %tmp.2
}
; We fail to reach a fixpoint, because sunk instructions get revisited too
; early. In @test2 the sunk add is revisited before the dominating condition
; is visited and added to the DomConditionCache.
;; PHI use, sink divide before call.
define i32 @test2(i32 %x) nounwind ssp "instcombine-no-verify-fixpoint" {
; CHECK-LABEL: @test2(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[BB:%.*]]
; CHECK: bb:
; CHECK-NEXT: [[X_ADDR_17:%.*]] = phi i32 [ [[X:%.*]], [[ENTRY:%.*]] ], [ [[X_ADDR_0:%.*]], [[BB2:%.*]] ]
; CHECK-NEXT: [[I_06:%.*]] = phi i32 [ 0, [[ENTRY]] ], [ [[TMP4:%.*]], [[BB2]] ]
; CHECK-NEXT: [[TMP0:%.*]] = icmp eq i32 [[X_ADDR_17]], 0
; CHECK-NEXT: br i1 [[TMP0]], label [[BB1:%.*]], label [[BB2]]
; CHECK: bb1:
; CHECK-NEXT: [[TMP1:%.*]] = add nsw i32 [[X_ADDR_17]], 1
; CHECK-NEXT: [[TMP2:%.*]] = sdiv i32 [[TMP1]], [[X_ADDR_17]]
; CHECK-NEXT: [[TMP3:%.*]] = tail call i32 @bar() #[[ATTR3:[0-9]+]]
; CHECK-NEXT: br label [[BB2]]
; CHECK: bb2:
; CHECK-NEXT: [[X_ADDR_0]] = phi i32 [ [[TMP2]], [[BB1]] ], [ [[X_ADDR_17]], [[BB]] ]
; CHECK-NEXT: [[TMP4]] = add nuw nsw i32 [[I_06]], 1
; CHECK-NEXT: [[EXITCOND:%.*]] = icmp eq i32 [[TMP4]], 1000000
; CHECK-NEXT: br i1 [[EXITCOND]], label [[BB4:%.*]], label [[BB]]
; CHECK: bb4:
; CHECK-NEXT: ret i32 [[X_ADDR_0]]
;
entry:
br label %bb
bb: ; preds = %bb2, %entry
%x_addr.17 = phi i32 [ %x, %entry ], [ %x_addr.0, %bb2 ] ; <i32> [#uses=4]
%i.06 = phi i32 [ 0, %entry ], [ %4, %bb2 ] ; <i32> [#uses=1]
%0 = add nsw i32 %x_addr.17, 1 ; <i32> [#uses=1]
%1 = sdiv i32 %0, %x_addr.17 ; <i32> [#uses=1]
%2 = icmp eq i32 %x_addr.17, 0 ; <i1> [#uses=1]
br i1 %2, label %bb1, label %bb2
bb1: ; preds = %bb
%3 = tail call i32 @bar() nounwind ; <i32> [#uses=0]
br label %bb2
bb2: ; preds = %bb, %bb1
%x_addr.0 = phi i32 [ %1, %bb1 ], [ %x_addr.17, %bb ] ; <i32> [#uses=2]
%4 = add nsw i32 %i.06, 1 ; <i32> [#uses=2]
%exitcond = icmp eq i32 %4, 1000000 ; <i1> [#uses=1]
br i1 %exitcond, label %bb4, label %bb
bb4: ; preds = %bb2
ret i32 %x_addr.0
}
declare i32 @bar()
define i32 @test3(ptr nocapture readonly %P, i32 %i) {
; CHECK-LABEL: @test3(
; CHECK-NEXT: entry:
; CHECK-NEXT: switch i32 [[I:%.*]], label [[SW_EPILOG:%.*]] [
; CHECK-NEXT: i32 5, label [[SW_BB:%.*]]
; CHECK-NEXT: i32 2, label [[SW_BB]]
; CHECK-NEXT: ]
; CHECK: sw.bb:
; CHECK-NEXT: [[IDXPROM:%.*]] = sext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i32, ptr [[P:%.*]], i64 [[IDXPROM]]
; CHECK-NEXT: [[TMP0:%.*]] = load i32, ptr [[ARRAYIDX]], align 4
; CHECK-NEXT: [[ADD:%.*]] = add nsw i32 [[TMP0]], [[I]]
; CHECK-NEXT: br label [[SW_EPILOG]]
; CHECK: sw.epilog:
; CHECK-NEXT: [[SUM_0:%.*]] = phi i32 [ [[ADD]], [[SW_BB]] ], [ 0, [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[SUM_0]]
;
entry:
%idxprom = sext i32 %i to i64
%arrayidx = getelementptr inbounds i32, ptr %P, i64 %idxprom
%0 = load i32, ptr %arrayidx, align 4
switch i32 %i, label %sw.epilog [
i32 5, label %sw.bb
i32 2, label %sw.bb
]
sw.bb: ; preds = %entry, %entry
%add = add nsw i32 %0, %i
br label %sw.epilog
sw.epilog: ; preds = %entry, %sw.bb
%sum.0 = phi i32 [ %add, %sw.bb ], [ 0, %entry ]
ret i32 %sum.0
}
declare i32 @foo(i32, i32)
; Two uses in a single user. We can still sink the instruction (tmp.9).
define i32 @test4(i32 %A, i32 %B, i1 %C) {
; CHECK-LABEL: @test4(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[C:%.*]], label [[THEN:%.*]], label [[ENDIF:%.*]]
; CHECK: then:
; CHECK-NEXT: [[TMP_9:%.*]] = add i32 [[B:%.*]], [[A:%.*]]
; CHECK-NEXT: [[RES:%.*]] = call i32 @foo(i32 [[TMP_9]], i32 [[TMP_9]])
; CHECK-NEXT: ret i32 [[RES]]
; CHECK: endif:
; CHECK-NEXT: [[TMP_2:%.*]] = sdiv i32 [[A]], [[B]]
; CHECK-NEXT: ret i32 [[TMP_2]]
;
entry:
%tmp.2 = sdiv i32 %A, %B ; <i32> [#uses=1]
%tmp.9 = add i32 %B, %A ; <i32> [#uses=1]
br i1 %C, label %then, label %endif
then: ; preds = %entry
%res = call i32 @foo(i32 %tmp.9, i32 %tmp.9)
ret i32 %res
endif: ; preds = %entry
ret i32 %tmp.2
}
; Two uses in a single user (phi node). We just bail out.
define i32 @test5(ptr nocapture readonly %P, i32 %i, i1 %cond) {
; CHECK-LABEL: @test5(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[IDXPROM:%.*]] = sext i32 [[I:%.*]] to i64
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i32, ptr [[P:%.*]], i64 [[IDXPROM]]
; CHECK-NEXT: [[TMP0:%.*]] = load i32, ptr [[ARRAYIDX]], align 4
; CHECK-NEXT: br i1 [[COND:%.*]], label [[DISPATCHBB:%.*]], label [[SW_EPILOG:%.*]]
; CHECK: dispatchBB:
; CHECK-NEXT: [[ADD:%.*]] = shl nsw i32 [[I]], 1
; CHECK-NEXT: br label [[SW_EPILOG]]
; CHECK: sw.bb:
; CHECK-NEXT: br label [[SW_EPILOG]]
; CHECK: sw.epilog:
; CHECK-NEXT: [[SUM_0:%.*]] = phi i32 [ [[TMP0]], [[SW_BB:%.*]] ], [ [[ADD]], [[DISPATCHBB]] ], [ [[TMP0]], [[ENTRY:%.*]] ]
; CHECK-NEXT: ret i32 [[SUM_0]]
;
entry:
%idxprom = sext i32 %i to i64
%arrayidx = getelementptr inbounds i32, ptr %P, i64 %idxprom
%0 = load i32, ptr %arrayidx, align 4
br i1 %cond, label %dispatchBB, label %sw.epilog
dispatchBB:
%add = add nsw i32 %i, %i
br label %sw.epilog
sw.bb: ; preds = %entry, %entry
br label %sw.epilog
sw.epilog: ; preds = %entry, %sw.bb
%sum.0 = phi i32 [ %0, %sw.bb ], [ %add, %dispatchBB ], [ %0, %entry ]
ret i32 %sum.0
}
; Multiple uses but from same BB. We can sink.
define i32 @test6(ptr nocapture readonly %P, i32 %i, i1 %cond) {
; CHECK-LABEL: @test6(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[ADD:%.*]] = shl nsw i32 [[I:%.*]], 1
; CHECK-NEXT: br label [[DISPATCHBB:%.*]]
; CHECK: dispatchBB:
; CHECK-NEXT: [[IDXPROM:%.*]] = sext i32 [[I]] to i64
; CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds i32, ptr [[P:%.*]], i64 [[IDXPROM]]
; CHECK-NEXT: [[TMP0:%.*]] = load i32, ptr [[ARRAYIDX]], align 4
; CHECK-NEXT: switch i32 [[I]], label [[SW_BB:%.*]] [
; CHECK-NEXT: i32 5, label [[SW_EPILOG:%.*]]
; CHECK-NEXT: i32 2, label [[SW_EPILOG]]
; CHECK-NEXT: ]
; CHECK: sw.bb:
; CHECK-NEXT: br label [[SW_EPILOG]]
; CHECK: sw.epilog:
; CHECK-NEXT: [[SUM_0:%.*]] = phi i32 [ [[ADD]], [[SW_BB]] ], [ [[TMP0]], [[DISPATCHBB]] ], [ [[TMP0]], [[DISPATCHBB]] ]
; CHECK-NEXT: ret i32 [[SUM_0]]
;
entry:
%idxprom = sext i32 %i to i64
%arrayidx = getelementptr inbounds i32, ptr %P, i64 %idxprom
%0 = load i32, ptr %arrayidx, align 4
%add = add nsw i32 %i, %i
br label %dispatchBB
dispatchBB:
switch i32 %i, label %sw.bb [
i32 5, label %sw.epilog
i32 2, label %sw.epilog
]
sw.bb: ; preds = %entry, %entry
br label %sw.epilog
sw.epilog: ; preds = %entry, %sw.bb
%sum.0 = phi i32 [ %add, %sw.bb ], [ %0, %dispatchBB ], [ %0, %dispatchBB ]
ret i32 %sum.0
}
declare void @checkd(double)
declare double @log(double) willreturn nounwind readnone
define void @test7(i1 %cond, double %d) {
; CHECK-LABEL: @test7(
; CHECK-NEXT: br i1 [[COND:%.*]], label [[IF:%.*]], label [[ELSE:%.*]]
; CHECK: if:
; CHECK-NEXT: [[A:%.*]] = call double @log(double [[D:%.*]])
; CHECK-NEXT: call void @checkd(double [[A]])
; CHECK-NEXT: ret void
; CHECK: else:
; CHECK-NEXT: ret void
;
%A = call double @log(double %d)
br i1 %cond, label %if, label %else
if:
call void @checkd(double %A)
ret void
else:
ret void
}
declare void @abort()
declare { i64, i1 } @llvm.umul.with.overflow.i64(i64, i64)
declare void @dummy(i64)
; Two uses in two different users of a single successor block. We can sink.
define i64 @test8(i64 %c) {
; CHECK-LABEL: @test8(
; CHECK-NEXT: bb1:
; CHECK-NEXT: [[OVERFLOW:%.*]] = icmp ugt i64 [[C:%.*]], 2305843009213693951
; CHECK-NEXT: br i1 [[OVERFLOW]], label [[ABORT:%.*]], label [[BB2:%.*]]
; CHECK: bb2:
; CHECK-NEXT: call void @dummy(i64 8)
; CHECK-NEXT: ret i64 8
; CHECK: abort:
; CHECK-NEXT: call void @abort()
; CHECK-NEXT: unreachable
;
bb1:
%mul = tail call { i64, i1 } @llvm.umul.with.overflow.i64(i64 %c, i64 8)
%overflow = extractvalue { i64, i1 } %mul, 1
%select = select i1 %overflow, i64 0, i64 8
br i1 %overflow, label %abort, label %bb2
bb2:
call void @dummy(i64 %select)
ret i64 %select
abort:
call void @abort()
unreachable
}
; Loads marked invariant can be sunk past potential memory writes.
define i32 @invariant_load_metadata(ptr %p, i1 %cond) {
; CHECK-LABEL: @invariant_load_metadata(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[COND:%.*]], label [[BLOCK:%.*]], label [[END:%.*]]
; CHECK: block:
; CHECK-NEXT: call void @fn()
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[V:%.*]] = load i32, ptr [[P:%.*]], align 4, !invariant.load [[META0:![0-9]+]]
; CHECK-NEXT: ret i32 [[V]]
;
entry:
%v = load i32, ptr %p, !invariant.load !0
br i1 %cond, label %block, label %end
block:
call void @fn()
br label %end
end:
ret i32 %v
}
; Loads not marked invariant cannot be sunk past potential memory writes.
define i32 @invariant_load_neg(ptr %p, i1 %cond) {
; CHECK-LABEL: @invariant_load_neg(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[V:%.*]] = load i32, ptr [[P:%.*]], align 4
; CHECK-NEXT: br i1 [[COND:%.*]], label [[BLOCK:%.*]], label [[END:%.*]]
; CHECK: block:
; CHECK-NEXT: call void @fn()
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: ret i32 [[V]]
;
entry:
%v = load i32, ptr %p
br i1 %cond, label %block, label %end
block:
call void @fn()
br label %end
end:
ret i32 %v
}
; Loads that aren't marked invariant but used in one branch
; can be sunk to that branch.
define void @invariant_load_use_in_br(ptr %p, i1 %cond) {
; CHECK-LABEL: @invariant_load_use_in_br(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[COND:%.*]], label [[TRUE_BR:%.*]], label [[FALSE_BR:%.*]]
; CHECK: true.br:
; CHECK-NEXT: call void @fn()
; CHECK-NEXT: br label [[EXIT:%.*]]
; CHECK: false.br:
; CHECK-NEXT: [[VAL:%.*]] = load i32, ptr [[P:%.*]], align 4
; CHECK-NEXT: call void @fn(i32 [[VAL]])
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
%val = load i32, ptr %p
br i1 %cond, label %true.br, label %false.br
true.br:
call void @fn()
br label %exit
false.br:
call void @fn(i32 %val)
br label %exit
exit:
ret void
}
; Invariant loads marked with metadata can be sunk past calls.
define void @invariant_load_metadata_call(ptr %p, i1 %cond) {
; CHECK-LABEL: @invariant_load_metadata_call(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @fn()
; CHECK-NEXT: br i1 [[COND:%.*]], label [[TRUE_BR:%.*]], label [[FALSE_BR:%.*]]
; CHECK: true.br:
; CHECK-NEXT: call void @fn()
; CHECK-NEXT: br label [[EXIT:%.*]]
; CHECK: false.br:
; CHECK-NEXT: [[VAL:%.*]] = load i32, ptr [[P:%.*]], align 4, !invariant.load [[META0]]
; CHECK-NEXT: call void @fn(i32 [[VAL]])
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
%val = load i32, ptr %p, !invariant.load !0
call void @fn()
br i1 %cond, label %true.br, label %false.br
true.br:
call void @fn()
br label %exit
false.br:
call void @fn(i32 %val)
br label %exit
exit:
ret void
}
declare void @fn()
!0 = !{}
|
