llvm/test/Transforms/InstCombine/mul.ll
Chris Lattner d2c58366d8 generalize a transformation even more: we don't care whether the
input the the mul is a zext from bool, just that it is all zeros
other than the low bit.  This fixes some phase ordering issues
that would cause us to miss some xforms in mul.ll when the worklist
is visited differently.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83794 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-11 21:29:45 +00:00

117 lines
3.0 KiB
LLVM

; This test makes sure that mul instructions are properly eliminated.
; RUN: opt < %s -instcombine -S | not grep mul
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 = fmul 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
}
; PR2642
define internal void @test13(<4 x float>*) {
load <4 x float>* %0, align 1
fmul <4 x float> %2, < float 1.000000e+00, float 1.000000e+00, float 1.000000e+00, float 1.000000e+00 >
store <4 x float> %3, <4 x float>* %0, align 1
ret void
}
define <16 x i8> @test14(<16 x i8> %a) {
%b = mul <16 x i8> %a, zeroinitializer
ret <16 x i8> %b
}
; rdar://7293527
define i32 @test15(i32 %A, i32 %B) {
entry:
%shl = shl i32 1, %B
%m = mul i32 %shl, %A
ret i32 %m
}
; X * Y (when Y is 0 or 1) --> x & (0-Y)
define i32 @test16(i32 %b, i1 %c) {
%d = zext i1 %c to i32 ; <i32> [#uses=1]
; e = b & (a >> 31)
%e = mul i32 %d, %b ; <i32> [#uses=1]
ret i32 %e
}
; X * Y (when Y is 0 or 1) --> x & (0-Y)
define i32 @test17(i32 %a, i32 %b) {
%a.lobit = lshr i32 %a, 31
%e = mul i32 %a.lobit, %b
ret i32 %e
}