1 ; Test that the ffs* library call simplifier works correctly. 2 ; 3 ; RUN: opt < %s -instcombine -S | FileCheck %s 4 ; RUN: opt < %s -mtriple i386-pc-linux -instcombine -S | FileCheck %s -check-prefix=CHECK-FFS 5 ; RUN: opt -instcombine -mtriple=arm64-apple-ios9.0 -S %s | FileCheck --check-prefix=CHECK-FFS %s 6 ; RUN: opt -instcombine -mtriple=arm64-apple-tvos9.0 -S %s | FileCheck --check-prefix=CHECK-FFS %s 7 ; RUN: opt -instcombine -mtriple=thumbv7k-apple-watchos2.0 -S %s | FileCheck --check-prefix=CHECK-FFS %s 8 ; RUN: opt -instcombine -mtriple=x86_64-apple-macosx10.11 -S %s | FileCheck --check-prefix=CHECK-FFS %s 9 ; RUN: opt -instcombine -mtriple=x86_64-freebsd-gnu -S %s | FileCheck --check-prefix=CHECK-FFS %s 10 11 declare i32 @ffs(i32) 12 declare i32 @ffsl(i32) 13 declare i32 @ffsll(i64) 14 15 ; Check ffs(0) -> 0. 16 17 define i32 @test_simplify1() { 18 ; CHECK-LABEL: @test_simplify1( 19 %ret = call i32 @ffs(i32 0) 20 ret i32 %ret 21 ; CHECK-NEXT: ret i32 0 22 } 23 24 define i32 @test_simplify2() { 25 ; CHECK-FFS-LABEL: @test_simplify2( 26 %ret = call i32 @ffsl(i32 0) 27 ret i32 %ret 28 ; CHECK-FFS-NEXT: ret i32 0 29 } 30 31 define i32 @test_simplify3() { 32 ; CHECK-FFS-LABEL: @test_simplify3( 33 %ret = call i32 @ffsll(i64 0) 34 ret i32 %ret 35 ; CHECK-FFS-NEXT: ret i32 0 36 } 37 38 ; Check ffs(c) -> cttz(c) + 1, where 'c' is a constant. 39 40 define i32 @test_simplify4() { 41 ; CHECK-LABEL: @test_simplify4( 42 %ret = call i32 @ffs(i32 1) 43 ret i32 %ret 44 ; CHECK-NEXT: ret i32 1 45 } 46 47 define i32 @test_simplify5() { 48 ; CHECK-LABEL: @test_simplify5( 49 %ret = call i32 @ffs(i32 2048) 50 ret i32 %ret 51 ; CHECK-NEXT: ret i32 12 52 } 53 54 define i32 @test_simplify6() { 55 ; CHECK-LABEL: @test_simplify6( 56 %ret = call i32 @ffs(i32 65536) 57 ret i32 %ret 58 ; CHECK-NEXT: ret i32 17 59 } 60 61 define i32 @test_simplify7() { 62 ; CHECK-FFS-LABEL: @test_simplify7( 63 %ret = call i32 @ffsl(i32 65536) 64 ret i32 %ret 65 ; CHECK-FFS-NEXT: ret i32 17 66 } 67 68 define i32 @test_simplify8() { 69 ; CHECK-FFS-LABEL: @test_simplify8( 70 %ret = call i32 @ffsll(i64 1024) 71 ret i32 %ret 72 ; CHECK-FFS-NEXT: ret i32 11 73 } 74 75 define i32 @test_simplify9() { 76 ; CHECK-FFS-LABEL: @test_simplify9( 77 %ret = call i32 @ffsll(i64 65536) 78 ret i32 %ret 79 ; CHECK-FFS-NEXT: ret i32 17 80 } 81 82 define i32 @test_simplify10() { 83 ; CHECK-FFS-LABEL: @test_simplify10( 84 %ret = call i32 @ffsll(i64 17179869184) 85 ret i32 %ret 86 ; CHECK-FFS-NEXT: ret i32 35 87 } 88 89 define i32 @test_simplify11() { 90 ; CHECK-FFS-LABEL: @test_simplify11( 91 %ret = call i32 @ffsll(i64 281474976710656) 92 ret i32 %ret 93 ; CHECK-FFS-NEXT: ret i32 49 94 } 95 96 define i32 @test_simplify12() { 97 ; CHECK-FFS-LABEL: @test_simplify12( 98 %ret = call i32 @ffsll(i64 1152921504606846976) 99 ret i32 %ret 100 ; CHECK-FFS-NEXT: ret i32 61 101 } 102 103 ; Check ffs(x) -> x != 0 ? (i32)llvm.cttz(x) + 1 : 0. 104 105 define i32 @test_simplify13(i32 %x) { 106 ; CHECK-LABEL: @test_simplify13( 107 %ret = call i32 @ffs(i32 %x) 108 ; CHECK-NEXT: [[CTTZ:%[a-z0-9]+]] = call i32 @llvm.cttz.i32(i32 %x, i1 true) 109 ; CHECK-NEXT: [[INC:%[a-z0-9]+]] = add nuw nsw i32 [[CTTZ]], 1 110 ; CHECK-NEXT: [[CMP:%[a-z0-9]+]] = icmp ne i32 %x, 0 111 ; CHECK-NEXT: [[RET:%[a-z0-9]+]] = select i1 [[CMP]], i32 [[INC]], i32 0 112 ret i32 %ret 113 ; CHECK-NEXT: ret i32 [[RET]] 114 } 115 116 define i32 @test_simplify14(i32 %x) { 117 ; CHECK-FFS-LABEL: @test_simplify14( 118 %ret = call i32 @ffsl(i32 %x) 119 ; CHECK-FFS-NEXT: [[CTTZ:%[a-z0-9]+]] = call i32 @llvm.cttz.i32(i32 %x, i1 true) 120 ; CHECK-FFS-NEXT: [[INC:%[a-z0-9]+]] = add nuw nsw i32 [[CTTZ]], 1 121 ; CHECK-FFS-NEXT: [[CMP:%[a-z0-9]+]] = icmp ne i32 %x, 0 122 ; CHECK-FFS-NEXT: [[RET:%[a-z0-9]+]] = select i1 [[CMP]], i32 [[INC]], i32 0 123 ret i32 %ret 124 ; CHECK-FFS-NEXT: ret i32 [[RET]] 125 } 126 127 define i32 @test_simplify15(i64 %x) { 128 ; CHECK-FFS-LABEL: @test_simplify15( 129 %ret = call i32 @ffsll(i64 %x) 130 ; CHECK-FFS-NEXT: [[CTTZ:%[a-z0-9]+]] = call i64 @llvm.cttz.i64(i64 %x, i1 true) 131 ; CHECK-FFS-NEXT: [[INC:%[a-z0-9]+]] = add nuw nsw i64 [[CTTZ]], 1 132 ; CHECK-FFS-NEXT: [[TRUNC:%[a-z0-9]+]] = trunc i64 [[INC]] to i32 133 ; CHECK-FFS-NEXT: [[CMP:%[a-z0-9]+]] = icmp ne i64 %x, 0 134 ; CHECK-FFS-NEXT: [[RET:%[a-z0-9]+]] = select i1 [[CMP]], i32 [[TRUNC]], i32 0 135 ret i32 %ret 136 ; CHECK-FFS-NEXT: ret i32 [[RET]] 137 } 138
