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|
; RUN: opt < %s -indvars -S | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
; IV with constant start, preinc and postinc sign extends, with and without NSW.
; IV rewrite only removes one sext. WidenIVs removes all three.
define void @postincConstIV(i8* %base, i32 %limit) nounwind {
entry:
br label %loop
; CHECK: loop:
; CHECK-NOT: sext
; CHECK: exit:
loop:
%iv = phi i32 [ %postiv, %loop ], [ 0, %entry ]
%ivnsw = phi i32 [ %postivnsw, %loop ], [ 0, %entry ]
%preofs = sext i32 %iv to i64
%preadr = getelementptr i8, i8* %base, i64 %preofs
store i8 0, i8* %preadr
%postiv = add i32 %iv, 1
%postofs = sext i32 %postiv to i64
%postadr = getelementptr i8, i8* %base, i64 %postofs
store i8 0, i8* %postadr
%postivnsw = add nsw i32 %ivnsw, 1
%postofsnsw = sext i32 %postivnsw to i64
%postadrnsw = getelementptr i8, i8* %base, i64 %postofsnsw
store i8 0, i8* %postadrnsw
%cond = icmp sgt i32 %limit, %iv
br i1 %cond, label %loop, label %exit
exit:
br label %return
return:
ret void
}
; IV with nonconstant start, preinc and postinc sign extends,
; with and without NSW.
; As with postincConstIV, WidenIVs removes all three sexts.
define void @postincVarIV(i8* %base, i32 %init, i32 %limit) nounwind {
entry:
%precond = icmp sgt i32 %limit, %init
br i1 %precond, label %loop, label %return
; CHECK: loop:
; CHECK-NOT: sext
; CHECK: exit:
loop:
%iv = phi i32 [ %postiv, %loop ], [ %init, %entry ]
%ivnsw = phi i32 [ %postivnsw, %loop ], [ %init, %entry ]
%preofs = sext i32 %iv to i64
%preadr = getelementptr i8, i8* %base, i64 %preofs
store i8 0, i8* %preadr
%postiv = add i32 %iv, 1
%postofs = sext i32 %postiv to i64
%postadr = getelementptr i8, i8* %base, i64 %postofs
store i8 0, i8* %postadr
%postivnsw = add nsw i32 %ivnsw, 1
%postofsnsw = sext i32 %postivnsw to i64
%postadrnsw = getelementptr i8, i8* %base, i64 %postofsnsw
store i8 0, i8* %postadrnsw
%cond = icmp sgt i32 %limit, %postiv
br i1 %cond, label %loop, label %exit
exit:
br label %return
return:
ret void
}
; Test sign extend elimination in the inner and outer loop.
; %outercount is straightforward to widen, besides being in an outer loop.
; %innercount is currently blocked by lcssa, so is not widened.
; %inneriv can be widened only after proving it has no signed-overflow
; based on the loop test.
define void @nestedIV(i8* %address, i32 %limit) nounwind {
entry:
%limitdec = add i32 %limit, -1
br label %outerloop
; CHECK: outerloop:
;
; Eliminate %ofs1 after widening outercount.
; CHECK-NOT: sext
; CHECK: getelementptr
;
; IV rewriting hoists a gep into this block. We don't like that.
; CHECK-NOT: getelementptr
outerloop:
%outercount = phi i32 [ %outerpostcount, %outermerge ], [ 0, %entry ]
%innercount = phi i32 [ %innercount.merge, %outermerge ], [ 0, %entry ]
%outercountdec = add i32 %outercount, -1
%ofs1 = sext i32 %outercountdec to i64
%adr1 = getelementptr i8, i8* %address, i64 %ofs1
store i8 0, i8* %adr1
br label %innerpreheader
innerpreheader:
%innerprecmp = icmp sgt i32 %limitdec, %innercount
br i1 %innerprecmp, label %innerloop, label %outermerge
; CHECK: innerloop:
;
; Eliminate %ofs2 after widening inneriv.
; Eliminate %ofs3 after normalizing sext(innerpostiv)
; CHECK-NOT: sext
; CHECK: getelementptr
;
; FIXME: We should check that indvars does not increase the number of
; IVs in this loop. sext elimination plus LFTR currently results in 2 final
; IVs. Waiting to remove LFTR.
innerloop:
%inneriv = phi i32 [ %innerpostiv, %innerloop ], [ %innercount, %innerpreheader ]
%innerpostiv = add i32 %inneriv, 1
%ofs2 = sext i32 %inneriv to i64
%adr2 = getelementptr i8, i8* %address, i64 %ofs2
store i8 0, i8* %adr2
%ofs3 = sext i32 %innerpostiv to i64
%adr3 = getelementptr i8, i8* %address, i64 %ofs3
store i8 0, i8* %adr3
%innercmp = icmp sgt i32 %limitdec, %innerpostiv
br i1 %innercmp, label %innerloop, label %innerexit
innerexit:
%innercount.lcssa = phi i32 [ %innerpostiv, %innerloop ]
br label %outermerge
; CHECK: outermerge:
;
; Eliminate %ofs4 after widening outercount
; CHECK-NOT: sext
; CHECK: getelementptr
;
; TODO: Eliminate %ofs5 after removing lcssa
outermerge:
%innercount.merge = phi i32 [ %innercount.lcssa, %innerexit ], [ %innercount, %innerpreheader ]
%ofs4 = sext i32 %outercount to i64
%adr4 = getelementptr i8, i8* %address, i64 %ofs4
store i8 0, i8* %adr4
%ofs5 = sext i32 %innercount.merge to i64
%adr5 = getelementptr i8, i8* %address, i64 %ofs5
store i8 0, i8* %adr5
%outerpostcount = add i32 %outercount, 1
%tmp47 = icmp slt i32 %outerpostcount, %limit
br i1 %tmp47, label %outerloop, label %return
return:
ret void
}
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