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| author | Duncan Sands <baldrick@free.fr> | 2008-02-13 18:01:53 +0000 |
|---|---|---|
| committer | Duncan Sands <baldrick@free.fr> | 2008-02-13 18:01:53 +0000 |
| commit | d462ba853981d45bf9c777564e79dc9e1c850ca6 (patch) | |
| tree | 7c160428925fb88c8e140a63491831477f3d02e2 /test/CodeGen | |
| parent | 82f0a09c1036c8651f0aa01d1f635abf9460d9f8 (diff) | |
| download | external_llvm-d462ba853981d45bf9c777564e79dc9e1c850ca6.zip external_llvm-d462ba853981d45bf9c777564e79dc9e1c850ca6.tar.gz external_llvm-d462ba853981d45bf9c777564e79dc9e1c850ca6.tar.bz2 | |
Teach LegalizeTypes how to expand and promote CTLZ,
CTTZ and CTPOP. The expansion code differs from
that in LegalizeDAG in that it chooses to take the
CTLZ/CTTZ count from the Hi/Lo part depending on
whether the Hi/Lo value is zero, not on whether
CTLZ/CTTZ of Hi/Lo returned 32 (or whatever the
width of the type is) for it. I made this change
because the optimizers may well know that Hi/Lo
is zero and exploit it. The promotion code for
CTTZ also differs from that in LegalizeDAG: it
uses an "or" to get the right result when the
original value is zero, rather than using a compare
and select. This also means the value doesn't
need to be zero extended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47075 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/CodeGen')
| -rw-r--r-- | test/CodeGen/Generic/2008-02-04-Ctlz.ll | 23 |
1 files changed, 11 insertions, 12 deletions
diff --git a/test/CodeGen/Generic/2008-02-04-Ctlz.ll b/test/CodeGen/Generic/2008-02-04-Ctlz.ll index 5a560aa..4639b6f 100644 --- a/test/CodeGen/Generic/2008-02-04-Ctlz.ll +++ b/test/CodeGen/Generic/2008-02-04-Ctlz.ll @@ -1,22 +1,21 @@ ; RUN: llvm-as < %s | llc -@.str3 = external constant [56 x i8] ; <[56 x i8]*> [#uses=1] +@.str = internal constant [14 x i8] c"%lld %d %d %d\00" -define i32 @main() nounwind { +define i32 @main(i64 %arg) nounwind { entry: - br label %bb30 - -bb30: ; preds = %bb30, %entry - %l.024 = phi i64 [ -10000, %entry ], [ 0, %bb30 ] ; <i64> [#uses=2] - %tmp37 = tail call i64 @llvm.ctlz.i64( i64 %l.024 ) ; <i64> [#uses=1] - trunc i64 %tmp37 to i32 ; <i32>:0 [#uses=1] - %tmp40 = tail call i32 (i8*, ...)* @printf( i8* noalias getelementptr ([56 x i8]* @.str3, i32 0, i32 0), i64 %l.024, i32 %0, i32 0, i32 0 ) nounwind ; <i32> [#uses=0] - br i1 false, label %bb30, label %bb9.i - -bb9.i: ; preds = %bb30 + %tmp37 = tail call i64 @llvm.ctlz.i64( i64 %arg ) ; <i64> [#uses=1] + %tmp47 = tail call i64 @llvm.cttz.i64( i64 %arg ) ; <i64> [#uses=1] + %tmp57 = tail call i64 @llvm.ctpop.i64( i64 %arg ) ; <i64> [#uses=1] + %tmp38 = trunc i64 %tmp37 to i32 ; <i32>:0 [#uses=1] + %tmp48 = trunc i64 %tmp47 to i32 ; <i32>:0 [#uses=1] + %tmp58 = trunc i64 %tmp57 to i32 ; <i32>:0 [#uses=1] + %tmp40 = tail call i32 (i8*, ...)* @printf( i8* noalias getelementptr ([14 x i8]* @.str, i32 0, i32 0), i64 %arg, i32 %tmp38, i32 %tmp48, i32 %tmp58 ) nounwind ; <i32> [#uses=0] ret i32 0 } declare i32 @printf(i8* noalias , ...) nounwind declare i64 @llvm.ctlz.i64(i64) nounwind readnone +declare i64 @llvm.cttz.i64(i64) nounwind readnone +declare i64 @llvm.ctpop.i64(i64) nounwind readnone |