forked from OSchip/llvm-project
55 lines
1.1 KiB
LLVM
55 lines
1.1 KiB
LLVM
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; RUN: opt < %s -instcombine -S | FileCheck %s
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target triple = "x86_64-unknown-freebsd11.0"
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define i32 @myfls() {
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; CHECK-LABEL: @myfls(
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; CHECK-NEXT: ret i32 6
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;
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%call = call i32 @fls(i32 42)
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ret i32 %call
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}
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define i32 @myflsl() {
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; CHECK-LABEL: @myflsl(
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; CHECK-NEXT: ret i32 6
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;
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%patatino = call i32 @flsl(i64 42)
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ret i32 %patatino
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}
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define i32 @myflsll() {
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; CHECK-LABEL: @myflsll(
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; CHECK-NEXT: ret i32 6
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;
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%whatever = call i32 @flsll(i64 42)
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ret i32 %whatever
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}
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; Lower to llvm.ctlz() if the argument is not a constant
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define i32 @flsnotconst(i64 %z) {
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; CHECK-LABEL: @flsnotconst(
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; CHECK-NEXT: [[CTLZ:%.*]] = call i64 @llvm.ctlz.i64(i64 %z, i1 false), !range !0
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; CHECK-NEXT: [[TMP1:%.*]] = trunc i64 [[CTLZ]] to i32
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; CHECK-NEXT: [[TMP2:%.*]] = sub nsw i32 64, [[TMP1]]
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; CHECK-NEXT: ret i32 [[TMP2]]
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;
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%goo = call i32 @flsl(i64 %z)
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ret i32 %goo
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}
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; Make sure we lower fls(0) to 0 and not to `undef`.
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define i32 @flszero() {
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; CHECK-LABEL: @flszero(
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; CHECK-NEXT: ret i32 0
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;
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%zero = call i32 @fls(i32 0)
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ret i32 %zero
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}
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declare i32 @fls(i32)
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declare i32 @flsl(i64)
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declare i32 @flsll(i64)
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