1 ; RUN: opt < %s -indvars -S | FileCheck %s 2 ; 3 ; Make sure that indvars can perform LFTR without a canonical IV. 4 5 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64" 6 7 ; Perform LFTR using the original pointer-type IV. 8 9 ; for(char* p = base; p < base + n; ++p) { 10 ; *p = p-base; 11 ; } 12 define void @ptriv(i8* %base, i32 %n) nounwind { 13 entry: 14 %idx.ext = sext i32 %n to i64 15 %add.ptr = getelementptr inbounds i8, i8* %base, i64 %idx.ext 16 %cmp1 = icmp ult i8* %base, %add.ptr 17 br i1 %cmp1, label %for.body, label %for.end 18 19 ; CHECK: for.body: 20 ; CHECK: phi i8* 21 ; CHECK-NOT: phi 22 ; CHECK-NOT: add 23 ; CHECK: icmp ne i8* 24 ; CHECK: br i1 25 for.body: 26 %p.02 = phi i8* [ %base, %entry ], [ %incdec.ptr, %for.body ] 27 ; cruft to make the IV useful 28 %sub.ptr.lhs.cast = ptrtoint i8* %p.02 to i64 29 %sub.ptr.rhs.cast = ptrtoint i8* %base to i64 30 %sub.ptr.sub = sub i64 %sub.ptr.lhs.cast, %sub.ptr.rhs.cast 31 %conv = trunc i64 %sub.ptr.sub to i8 32 store i8 %conv, i8* %p.02 33 %incdec.ptr = getelementptr inbounds i8, i8* %p.02, i32 1 34 %cmp = icmp ult i8* %incdec.ptr, %add.ptr 35 br i1 %cmp, label %for.body, label %for.end 36 37 for.end: 38 ret void 39 } 40 41 ; This test checks that SCEVExpander can handle an outer loop that has been 42 ; simplified, and as a result the inner loop's exit test will be rewritten. 43 define void @expandOuterRecurrence(i32 %arg) nounwind { 44 entry: 45 %sub1 = sub nsw i32 %arg, 1 46 %cmp1 = icmp slt i32 0, %sub1 47 br i1 %cmp1, label %outer, label %exit 48 49 ; CHECK: outer: 50 ; CHECK: icmp slt 51 outer: 52 %i = phi i32 [ 0, %entry ], [ %i.inc, %outer.inc ] 53 %sub2 = sub nsw i32 %arg, %i 54 %sub3 = sub nsw i32 %sub2, 1 55 %cmp2 = icmp slt i32 0, %sub3 56 br i1 %cmp2, label %inner.ph, label %outer.inc 57 58 inner.ph: 59 br label %inner 60 61 ; CHECK: inner: 62 ; CHECK: br i1 63 inner: 64 %j = phi i32 [ 0, %inner.ph ], [ %j.inc, %inner ] 65 %j.inc = add nsw i32 %j, 1 66 %cmp3 = icmp slt i32 %j.inc, %sub3 67 br i1 %cmp3, label %inner, label %outer.inc 68 69 ; CHECK: outer.inc: 70 ; CHECK: icmp ne 71 ; CHECK: br i1 72 outer.inc: 73 %i.inc = add nsw i32 %i, 1 74 %cmp4 = icmp slt i32 %i.inc, %sub1 75 br i1 %cmp4, label %outer, label %exit 76 77 exit: 78 ret void 79 } 80 81 ; Force SCEVExpander to look for an existing well-formed phi. 82 ; Perform LFTR without generating extra preheader code. 83 define void @guardedloop([0 x double]* %matrix, [0 x double]* %vector, 84 i32 %irow, i32 %ilead) nounwind { 85 ; CHECK: entry: 86 ; CHECK-NOT: zext 87 ; CHECK-NOT: add 88 ; CHECK: loop: 89 ; CHECK: phi i64 90 ; CHECK: phi i64 91 ; CHECK-NOT: phi 92 ; CHECK: icmp ne 93 ; CHECK: br i1 94 entry: 95 %cmp = icmp slt i32 1, %irow 96 br i1 %cmp, label %loop, label %return 97 98 loop: 99 %rowidx = phi i32 [ 0, %entry ], [ %row.inc, %loop ] 100 %i = phi i32 [ 0, %entry ], [ %i.inc, %loop ] 101 %diagidx = add nsw i32 %rowidx, %i 102 %diagidxw = sext i32 %diagidx to i64 103 %matrixp = getelementptr inbounds [0 x double], [0 x double]* %matrix, i32 0, i64 %diagidxw 104 %v1 = load double, double* %matrixp 105 %iw = sext i32 %i to i64 106 %vectorp = getelementptr inbounds [0 x double], [0 x double]* %vector, i32 0, i64 %iw 107 %v2 = load double, double* %vectorp 108 %row.inc = add nsw i32 %rowidx, %ilead 109 %i.inc = add nsw i32 %i, 1 110 %cmp196 = icmp slt i32 %i.inc, %irow 111 br i1 %cmp196, label %loop, label %return 112 113 return: 114 ret void 115 } 116 117 ; Avoid generating extra code to materialize a trip count. Skip LFTR. 118 define void @unguardedloop([0 x double]* %matrix, [0 x double]* %vector, 119 i32 %irow, i32 %ilead) nounwind { 120 entry: 121 br label %loop 122 123 ; CHECK: entry: 124 ; CHECK-NOT: zext 125 ; CHECK-NOT: add 126 ; CHECK: loop: 127 ; CHECK: phi i64 128 ; CHECK: phi i64 129 ; CHECK-NOT: phi 130 ; CHECK: icmp slt 131 ; CHECK: br i1 132 loop: 133 %rowidx = phi i32 [ 0, %entry ], [ %row.inc, %loop ] 134 %i = phi i32 [ 0, %entry ], [ %i.inc, %loop ] 135 %diagidx = add nsw i32 %rowidx, %i 136 %diagidxw = sext i32 %diagidx to i64 137 %matrixp = getelementptr inbounds [0 x double], [0 x double]* %matrix, i32 0, i64 %diagidxw 138 %v1 = load double, double* %matrixp 139 %iw = sext i32 %i to i64 140 %vectorp = getelementptr inbounds [0 x double], [0 x double]* %vector, i32 0, i64 %iw 141 %v2 = load double, double* %vectorp 142 %row.inc = add nsw i32 %rowidx, %ilead 143 %i.inc = add nsw i32 %i, 1 144 %cmp196 = icmp slt i32 %i.inc, %irow 145 br i1 %cmp196, label %loop, label %return 146 147 return: 148 ret void 149 } 150 151 ; Remove %i which is only used by the exit test. 152 ; Verify that SCEV can still compute a backedge count from the sign 153 ; extended %n, used for pointer comparison by LFTR. 154 ; 155 ; TODO: Fix for PR13371 currently makes this impossible. See 156 ; IndVarSimplify.cpp hasConcreteDef(). We may want to change to undef rules. 157 define void @geplftr(i8* %base, i32 %x, i32 %y, i32 %n) nounwind { 158 entry: 159 %x.ext = sext i32 %x to i64 160 %add.ptr = getelementptr inbounds i8, i8* %base, i64 %x.ext 161 %y.ext = sext i32 %y to i64 162 %add.ptr10 = getelementptr inbounds i8, i8* %add.ptr, i64 %y.ext 163 %lim = add i32 %x, %n 164 %cmp.ph = icmp ult i32 %x, %lim 165 br i1 %cmp.ph, label %loop, label %exit 166 ; CHECK-LABEL: @geplftr( 167 ; CHECK: loop: 168 ; CHECK: phi i8* 169 ; DISABLE-NOT: phi // This check is currently disabled 170 ; CHECK: getelementptr 171 ; CHECK: store 172 ; DISABLE: icmp ne i8* // This check is currently disabled 173 ; CHECK: br i1 174 loop: 175 %i = phi i32 [ %x, %entry ], [ %inc, %loop ] 176 %aptr = phi i8* [ %add.ptr10, %entry ], [ %incdec.ptr, %loop ] 177 %incdec.ptr = getelementptr inbounds i8, i8* %aptr, i32 1 178 store i8 3, i8* %aptr 179 %inc = add i32 %i, 1 180 %cmp = icmp ult i32 %inc, %lim 181 br i1 %cmp, label %loop, label %exit 182 183 exit: 184 ret void 185 } 186 187 ; Exercise backedge taken count verification with a never-taken loop. 188 define void @nevertaken() nounwind uwtable ssp { 189 entry: 190 br label %loop 191 ; CHECK-LABEL: @nevertaken( 192 ; CHECK: loop: 193 ; CHECK-NOT: phi 194 ; CHECK-NOT: add 195 ; CHECK-NOT: icmp 196 ; CHECK: exit: 197 loop: 198 %i = phi i32 [ 0, %entry ], [ %inc, %loop ] 199 %inc = add nsw i32 %i, 1 200 %cmp = icmp sle i32 %inc, 0 201 br i1 %cmp, label %loop, label %exit 202 203 exit: 204 ret void 205 } 206 207 ; Test LFTR on an IV whose recurrence start is a non-unit pointer type. 208 define void @aryptriv([256 x i8]* %base, i32 %n) nounwind { 209 entry: 210 %ivstart = getelementptr inbounds [256 x i8], [256 x i8]* %base, i32 0, i32 0 211 %ivend = getelementptr inbounds [256 x i8], [256 x i8]* %base, i32 0, i32 %n 212 %cmp.ph = icmp ult i8* %ivstart, %ivend 213 br i1 %cmp.ph, label %loop, label %exit 214 215 ; CHECK: loop: 216 ; CHECK: phi i8* 217 ; CHECK-NOT: phi 218 ; CHECK: getelementptr 219 ; CHECK: store 220 ; CHECK: icmp ne i8* 221 ; CHECK: br i1 222 loop: 223 %aptr = phi i8* [ %ivstart, %entry ], [ %incdec.ptr, %loop ] 224 %incdec.ptr = getelementptr inbounds i8, i8* %aptr, i32 1 225 store i8 3, i8* %aptr 226 %cmp = icmp ult i8* %incdec.ptr, %ivend 227 br i1 %cmp, label %loop, label %exit 228 229 exit: 230 ret void 231 } 232
