; This test makes sure that mul instructions are properly eliminated. ; RUN: opt < %s -instcombine -S | FileCheck %s define i32 @test1(i32 %A) { ; CHECK-LABEL: @test1( %B = mul i32 %A, 1 ; [#uses=1] ret i32 %B ; CHECK: ret i32 %A } define i32 @test2(i32 %A) { ; CHECK-LABEL: @test2( ; Should convert to an add instruction %B = mul i32 %A, 2 ; [#uses=1] ret i32 %B ; CHECK: shl i32 %A, 1 } define i32 @test3(i32 %A) { ; CHECK-LABEL: @test3( ; This should disappear entirely %B = mul i32 %A, 0 ; [#uses=1] ret i32 %B ; CHECK: ret i32 0 } define double @test4(double %A) { ; CHECK-LABEL: @test4( ; This is safe for FP %B = fmul double 1.000000e+00, %A ; [#uses=1] ret double %B ; CHECK: ret double %A } define i32 @test5(i32 %A) { ; CHECK-LABEL: @test5( %B = mul i32 %A, 8 ; [#uses=1] ret i32 %B ; CHECK: shl i32 %A, 3 } define i8 @test6(i8 %A) { ; CHECK-LABEL: @test6( %B = mul i8 %A, 8 ; [#uses=1] %C = mul i8 %B, 8 ; [#uses=1] ret i8 %C ; CHECK: shl i8 %A, 6 } define i32 @test7(i32 %i) { ; CHECK-LABEL: @test7( %tmp = mul i32 %i, -1 ; [#uses=1] ret i32 %tmp ; CHECK: sub i32 0, %i } define i64 @test8(i64 %i) { ; CHECK-LABEL: @test8( %j = mul i64 %i, -1 ; [#uses=1] ret i64 %j ; CHECK: sub i64 0, %i } define i32 @test9(i32 %i) { ; CHECK-LABEL: @test9( %j = mul i32 %i, -1 ; [#uses=1] ret i32 %j ; CHECK: sub i32 0, %i } define i32 @test10(i32 %a, i32 %b) { ; CHECK-LABEL: @test10( %c = icmp slt i32 %a, 0 ; [#uses=1] %d = zext i1 %c to i32 ; [#uses=1] ; e = b & (a >> 31) %e = mul i32 %d, %b ; [#uses=1] ret i32 %e ; CHECK: [[TEST10:%.*]] = ashr i32 %a, 31 ; CHECK-NEXT: %e = and i32 [[TEST10]], %b ; CHECK-NEXT: ret i32 %e } define i32 @test11(i32 %a, i32 %b) { ; CHECK-LABEL: @test11( %c = icmp sle i32 %a, -1 ; [#uses=1] %d = zext i1 %c to i32 ; [#uses=1] ; e = b & (a >> 31) %e = mul i32 %d, %b ; [#uses=1] ret i32 %e ; CHECK: [[TEST11:%.*]] = ashr i32 %a, 31 ; CHECK-NEXT: %e = and i32 [[TEST11]], %b ; CHECK-NEXT: ret i32 %e } define i32 @test12(i32 %a, i32 %b) { ; CHECK-LABEL: @test12( %c = icmp ugt i32 %a, 2147483647 ; [#uses=1] %d = zext i1 %c to i32 ; [#uses=1] %e = mul i32 %d, %b ; [#uses=1] ret i32 %e ; CHECK: [[TEST12:%.*]] = ashr i32 %a, 31 ; CHECK-NEXT: %e = and i32 [[TEST12]], %b ; CHECK-NEXT: ret i32 %e } ; PR2642 define internal void @test13(<4 x float>*) { ; CHECK-LABEL: @test13( 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 ; CHECK-NEXT: ret void } define <16 x i8> @test14(<16 x i8> %a) { ; CHECK-LABEL: @test14( %b = mul <16 x i8> %a, zeroinitializer ret <16 x i8> %b ; CHECK-NEXT: ret <16 x i8> zeroinitializer } ; rdar://7293527 define i32 @test15(i32 %A, i32 %B) { ; CHECK-LABEL: @test15( entry: %shl = shl i32 1, %B %m = mul i32 %shl, %A ret i32 %m ; CHECK: shl i32 %A, %B } ; X * Y (when Y is 0 or 1) --> x & (0-Y) define i32 @test16(i32 %b, i1 %c) { ; CHECK-LABEL: @test16( %d = zext i1 %c to i32 ; [#uses=1] ; e = b & (a >> 31) %e = mul i32 %d, %b ; [#uses=1] ret i32 %e ; CHECK: [[TEST16:%.*]] = select i1 %c, i32 %b, i32 0 ; CHECK-NEXT: ret i32 [[TEST16]] } ; X * Y (when Y is 0 or 1) --> x & (0-Y) define i32 @test17(i32 %a, i32 %b) { ; CHECK-LABEL: @test17( %a.lobit = lshr i32 %a, 31 %e = mul i32 %a.lobit, %b ret i32 %e ; CHECK: [[TEST17:%.*]] = ashr i32 %a, 31 ; CHECK-NEXT: %e = and i32 [[TEST17]], %b ; CHECK-NEXT: ret i32 %e } define i32 @test18(i32 %A, i32 %B) { ; CHECK-LABEL: @test18( %C = and i32 %A, 1 %D = and i32 %B, 1 %E = mul i32 %C, %D %F = and i32 %E, 16 ret i32 %F ; CHECK-NEXT: ret i32 0 } declare {i32, i1} @llvm.smul.with.overflow.i32(i32, i32) declare void @use(i1) define i32 @test19(i32 %A, i32 %B) { ; CHECK-LABEL: @test19( %C = and i32 %A, 1 %D = and i32 %B, 1 ; It would be nice if we also started proving that this doesn't overflow. %E = call {i32, i1} @llvm.smul.with.overflow.i32(i32 %C, i32 %D) %F = extractvalue {i32, i1} %E, 0 %G = extractvalue {i32, i1} %E, 1 call void @use(i1 %G) %H = and i32 %F, 16 ret i32 %H ; CHECK: ret i32 0 }