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; RUN: llc < %s -march=x86 | FileCheck %s
; When doing sign extension, use the sext-load lowering to take advantage of
; x86's sign extension during loads.
;
; CHECK-LABEL: test1:
; CHECK: movsbl {{.*}}, %eax
; CHECK-NEXT: ret
define i32 @test1(i32 %X) nounwind {
entry:
%tmp12 = trunc i32 %X to i8 ; <i8> [#uses=1]
%tmp123 = sext i8 %tmp12 to i32 ; <i32> [#uses=1]
ret i32 %tmp123
}
; When using a sextload representation, ensure that the sign extension is
; preserved even when removing shifted-out low bits.
;
; CHECK-LABEL: test2:
; CHECK: movswl {{.*}}, %eax
; CHECK-NEXT: ret
define i32 @test2({i16, [6 x i8]}* %this) {
entry:
%b48 = getelementptr inbounds { i16, [6 x i8] }, { i16, [6 x i8] }* %this, i32 0, i32 1
%cast = bitcast [6 x i8]* %b48 to i48*
%bf.load = load i48, i48* %cast, align 2
%bf.ashr = ashr i48 %bf.load, 32
%bf.cast = trunc i48 %bf.ashr to i32
ret i32 %bf.cast
}
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