llvm-project/llvm/test/Transforms/InstCombine/mul.ll

81 lines
2.1 KiB
LLVM

; This test makes sure that mul instructions are properly eliminated.
;
; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep mul
; END.
define i32 @test1(i32 %A) {
%B = mul i32 %A, 1 ; <i32> [#uses=1]
ret i32 %B
}
define i32 @test2(i32 %A) {
; Should convert to an add instruction
%B = mul i32 %A, 2 ; <i32> [#uses=1]
ret i32 %B
}
define i32 @test3(i32 %A) {
; This should disappear entirely
%B = mul i32 %A, 0 ; <i32> [#uses=1]
ret i32 %B
}
define double @test4(double %A) {
; This is safe for FP
%B = mul double 1.000000e+00, %A ; <double> [#uses=1]
ret double %B
}
define i32 @test5(i32 %A) {
%B = mul i32 %A, 8 ; <i32> [#uses=1]
ret i32 %B
}
define i8 @test6(i8 %A) {
%B = mul i8 %A, 8 ; <i8> [#uses=1]
%C = mul i8 %B, 8 ; <i8> [#uses=1]
ret i8 %C
}
define i32 @test7(i32 %i) {
%tmp = mul i32 %i, -1 ; <i32> [#uses=1]
ret i32 %tmp
}
define i64 @test8(i64 %i) {
; tmp = sub 0, %i
%j = mul i64 %i, -1 ; <i64> [#uses=1]
ret i64 %j
}
define i32 @test9(i32 %i) {
; %j = sub 0, %i
%j = mul i32 %i, -1 ; <i32> [#uses=1]
ret i32 %j
}
define i32 @test10(i32 %a, i32 %b) {
%c = icmp slt i32 %a, 0 ; <i1> [#uses=1]
%d = zext i1 %c to i32 ; <i32> [#uses=1]
; e = b & (a >> 31)
%e = mul i32 %d, %b ; <i32> [#uses=1]
ret i32 %e
}
define i32 @test11(i32 %a, i32 %b) {
%c = icmp sle i32 %a, -1 ; <i1> [#uses=1]
%d = zext i1 %c to i32 ; <i32> [#uses=1]
; e = b & (a >> 31)
%e = mul i32 %d, %b ; <i32> [#uses=1]
ret i32 %e
}
define i32 @test12(i8 %a, i32 %b) {
%c = icmp ugt i8 %a, 127 ; <i1> [#uses=1]
%d = zext i1 %c to i32 ; <i32> [#uses=1]
; e = b & (a >> 31)
%e = mul i32 %d, %b ; <i32> [#uses=1]
ret i32 %e
}