llvm-6502/test/Transforms/InstCombine/rem.ll
Nick Lewycky c1a2a61201 Don't try to simplify urem and srem using arithmetic rules that don't work
under modulo (overflow). Fixes PR1933.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47987 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-06 06:48:30 +00:00

84 lines
1.5 KiB
LLVM

; This test makes sure that these instructions are properly eliminated.
;
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep rem
; END.
define i32 @test1(i32 %A) {
%B = srem i32 %A, 1 ; ISA constant 0
ret i32 %B
}
define i32 @test2(i32 %A) { ; 0 % X = 0, we don't need to preserve traps
%B = srem i32 0, %A
ret i32 %B
}
define i32 @test3(i32 %A) {
%B = urem i32 %A, 8
ret i32 %B
}
define i1 @test3a(i32 %A) {
%B = srem i32 %A, -8
%C = icmp ne i32 %B, 0
ret i1 %C
}
define i32 @test4(i32 %X, i1 %C) {
%V = select i1 %C, i32 1, i32 8
%R = urem i32 %X, %V
ret i32 %R
}
define i32 @test5(i32 %X, i8 %B) {
%shift.upgrd.1 = zext i8 %B to i32
%Amt = shl i32 32, %shift.upgrd.1
%V = urem i32 %X, %Amt
ret i32 %V
}
define i32 @test6(i32 %A) {
%B = srem i32 %A, 0 ;; undef
ret i32 %B
}
define i32 @test7(i32 %A) {
%B = mul i32 %A, 8
%C = srem i32 %B, 4
ret i32 %C
}
define i32 @test8(i32 %A) {
%B = shl i32 %A, 4
%C = srem i32 %B, 8
ret i32 %C
}
define i32 @test9(i32 %A) {
%B = mul i32 %A, 64
%C = urem i32 %B, 32
ret i32 %C
}
define i32 @test10(i8 %c) {
%tmp.1 = zext i8 %c to i32
%tmp.2 = mul i32 %tmp.1, 4
%tmp.3 = sext i32 %tmp.2 to i64
%tmp.5 = urem i64 %tmp.3, 4
%tmp.6 = trunc i64 %tmp.5 to i32
ret i32 %tmp.6
}
define i32 @test11(i32 %i) {
%tmp.1 = and i32 %i, -2
%tmp.3 = mul i32 %tmp.1, 2
%tmp.5 = urem i32 %tmp.3, 4
ret i32 %tmp.5
}
define i32 @test12(i32 %i) {
%tmp.1 = and i32 %i, -4
%tmp.5 = srem i32 %tmp.1, 2
ret i32 %tmp.5
}