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; RUN: llc < %s -march=x86 | FileCheck %s
define i32 @t1(i8* %X, i32 %i) {
; CHECK-LABEL: t1:
; CHECK-NOT: and
; CHECK: movzbl
; CHECK: movl (%{{...}},%{{...}},4),
; CHECK: ret
entry:
%tmp2 = shl i32 %i, 2
%tmp4 = and i32 %tmp2, 1020
%tmp7 = getelementptr i8, i8* %X, i32 %tmp4
%tmp78 = bitcast i8* %tmp7 to i32*
%tmp9 = load i32, i32* %tmp78
ret i32 %tmp9
}
define i32 @t2(i16* %X, i32 %i) {
; CHECK-LABEL: t2:
; CHECK-NOT: and
; CHECK: movzwl
; CHECK: movl (%{{...}},%{{...}},4),
; CHECK: ret
entry:
%tmp2 = shl i32 %i, 1
%tmp4 = and i32 %tmp2, 131070
%tmp7 = getelementptr i16, i16* %X, i32 %tmp4
%tmp78 = bitcast i16* %tmp7 to i32*
%tmp9 = load i32, i32* %tmp78
ret i32 %tmp9
}
define i32 @t3(i16* %i.ptr, i32* %arr) {
; This case is tricky. The lshr followed by a gep will produce a lshr followed
; by an and to remove the low bits. This can be simplified by doing the lshr by
; a greater constant and using the addressing mode to scale the result back up.
; To make matters worse, because of the two-phase zext of %i and their reuse in
; the function, the DAG can get confusing trying to re-use both of them and
; prevent easy analysis of the mask in order to match this.
; CHECK-LABEL: t3:
; CHECK-NOT: and
; CHECK: shrl
; CHECK: addl (%{{...}},%{{...}},4),
; CHECK: ret
entry:
%i = load i16, i16* %i.ptr
%i.zext = zext i16 %i to i32
%index = lshr i32 %i.zext, 11
%val.ptr = getelementptr inbounds i32, i32* %arr, i32 %index
%val = load i32, i32* %val.ptr
%sum = add i32 %val, %i.zext
ret i32 %sum
}
define i32 @t4(i16* %i.ptr, i32* %arr) {
; A version of @t3 that has more zero extends and more re-use of intermediate
; values. This exercise slightly different bits of canonicalization.
; CHECK-LABEL: t4:
; CHECK-NOT: and
; CHECK: shrl
; CHECK: addl (%{{...}},%{{...}},4),
; CHECK: ret
entry:
%i = load i16, i16* %i.ptr
%i.zext = zext i16 %i to i32
%index = lshr i32 %i.zext, 11
%index.zext = zext i32 %index to i64
%val.ptr = getelementptr inbounds i32, i32* %arr, i64 %index.zext
%val = load i32, i32* %val.ptr
%sum.1 = add i32 %val, %i.zext
%sum.2 = add i32 %sum.1, %index
ret i32 %sum.2
}
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