36 lines
1.3 KiB
LLVM
36 lines
1.3 KiB
LLVM
; RUN: opt < %s -instcombine -S > %t
|
|
; RUN: not grep lshr %t
|
|
; RUN: grep add %t | count 1
|
|
|
|
; Instcombine should be able to eliminate the lshr, because only
|
|
; bits in the operand which might be non-zero will be shifted
|
|
; off the end.
|
|
|
|
define i32 @hash_string(i8* nocapture %key) nounwind readonly {
|
|
entry:
|
|
%t0 = load i8* %key, align 1 ; <i8> [#uses=1]
|
|
%t1 = icmp eq i8 %t0, 0 ; <i1> [#uses=1]
|
|
br i1 %t1, label %bb2, label %bb
|
|
|
|
bb: ; preds = %bb, %entry
|
|
%indvar = phi i64 [ 0, %entry ], [ %tmp, %bb ] ; <i64> [#uses=2]
|
|
%k.04 = phi i32 [ 0, %entry ], [ %t8, %bb ] ; <i32> [#uses=2]
|
|
%cp.05 = getelementptr i8* %key, i64 %indvar ; <i8*> [#uses=1]
|
|
%t2 = shl i32 %k.04, 1 ; <i32> [#uses=1]
|
|
%t3 = lshr i32 %k.04, 14 ; <i32> [#uses=1]
|
|
%t4 = add i32 %t2, %t3 ; <i32> [#uses=1]
|
|
%t5 = load i8* %cp.05, align 1 ; <i8> [#uses=1]
|
|
%t6 = sext i8 %t5 to i32 ; <i32> [#uses=1]
|
|
%t7 = xor i32 %t6, %t4 ; <i32> [#uses=1]
|
|
%t8 = and i32 %t7, 16383 ; <i32> [#uses=2]
|
|
%tmp = add i64 %indvar, 1 ; <i64> [#uses=2]
|
|
%scevgep = getelementptr i8* %key, i64 %tmp ; <i8*> [#uses=1]
|
|
%t9 = load i8* %scevgep, align 1 ; <i8> [#uses=1]
|
|
%t10 = icmp eq i8 %t9, 0 ; <i1> [#uses=1]
|
|
br i1 %t10, label %bb2, label %bb
|
|
|
|
bb2: ; preds = %bb, %entry
|
|
%k.0.lcssa = phi i32 [ 0, %entry ], [ %t8, %bb ] ; <i32> [#uses=1]
|
|
ret i32 %k.0.lcssa
|
|
}
|