1 ; RUN: llc < %s 2 3 %Domain = type { i8*, i32, i32*, i32, i32, i32*, %Domain* } 4 @AConst = constant i32 123 ; <i32*> [#uses=1] 5 6 ; Test setting values of different constants in registers. 7 ; 8 define void @testConsts(i32 %N, float %X) { 9 %a = add i32 %N, 1 ; <i32> [#uses=0] 10 %i = add i32 %N, 12345678 ; <i32> [#uses=0] 11 %b = add i16 4, 3 ; <i16> [#uses=0] 12 %c = fadd float %X, 0.000000e+00 ; <float> [#uses=0] 13 %d = fadd float %X, 0x400921CAC0000000 ; <float> [#uses=0] 14 %f = add i32 -1, 10 ; <i32> [#uses=0] 15 %g = add i16 20, -1 ; <i16> [#uses=0] 16 %j = add i16 -1, 30 ; <i16> [#uses=0] 17 %h = add i8 40, -1 ; <i8> [#uses=0] 18 %k = add i8 -1, 50 ; <i8> [#uses=0] 19 ret void 20 } 21 22 ; A SetCC whose result is used should produce instructions to 23 ; compute the boolean value in a register. One whose result 24 ; is unused will only generate the condition code but not 25 ; the boolean result. 26 ; 27 define void @unusedBool(i32* %x, i32* %y) { 28 icmp eq i32* %x, %y ; <i1>:1 [#uses=1] 29 xor i1 %1, true ; <i1>:2 [#uses=0] 30 icmp ne i32* %x, %y ; <i1>:3 [#uses=0] 31 ret void 32 } 33 34 ; A constant argument to a Phi produces a Cast instruction in the 35 ; corresponding predecessor basic block. This checks a few things: 36 ; -- phi arguments coming from the bottom of the same basic block 37 ; (they should not be forward substituted in the machine code!) 38 ; -- code generation for casts of various types 39 ; -- use of immediate fields for integral constants of different sizes 40 ; -- branch on a constant condition 41 ; 42 define void @mergeConstants(i32* %x, i32* %y) { 43 ; <label>:0 44 br label %Top 45 46 Top: ; preds = %Next, %Top, %0 47 phi i32 [ 0, %0 ], [ 1, %Top ], [ 524288, %Next ] ; <i32>:1 [#uses=0] 48 phi float [ 0.000000e+00, %0 ], [ 1.000000e+00, %Top ], [ 2.000000e+00, %Next ] ; <float>:2 [#uses=0] 49 phi double [ 5.000000e-01, %0 ], [ 1.500000e+00, %Top ], [ 2.500000e+00, %Next ] 50 phi i1 [ true, %0 ], [ false, %Top ], [ true, %Next ] ; <i1>:4 [#uses=0] 51 br i1 true, label %Top, label %Next 52 53 Next: ; preds = %Top 54 br label %Top 55 } 56 57 58 59 ; A constant argument to a cast used only once should be forward substituted 60 ; and loaded where needed, which happens is: 61 ; -- User of cast has no immediate field 62 ; -- User of cast has immediate field but constant is too large to fit 63 ; or constant is not resolved until later (e.g., global address) 64 ; -- User of cast uses it as a call arg. or return value so it is an implicit 65 ; use but has to be loaded into a virtual register so that the reg. 66 ; allocator can allocate the appropriate phys. reg. for it 67 ; 68 define i32* @castconst(float) { 69 %castbig = trunc i64 99999999 to i32 ; <i32> [#uses=1] 70 %castsmall = trunc i64 1 to i32 ; <i32> [#uses=1] 71 %usebig = add i32 %castbig, %castsmall ; <i32> [#uses=0] 72 %castglob = bitcast i32* @AConst to i64* ; <i64*> [#uses=1] 73 %dummyl = load i64* %castglob ; <i64> [#uses=0] 74 %castnull = inttoptr i64 0 to i32* ; <i32*> [#uses=1] 75 ret i32* %castnull 76 } 77 78 ; Test branch-on-comparison-with-zero, in two ways: 79 ; 1. can be folded 80 ; 2. cannot be folded because result of comparison is used twice 81 ; 82 define void @testbool(i32 %A, i32 %B) { 83 br label %Top 84 85 Top: ; preds = %loop, %0 86 %D = add i32 %A, %B ; <i32> [#uses=2] 87 %E = sub i32 %D, -4 ; <i32> [#uses=1] 88 %C = icmp sle i32 %E, 0 ; <i1> [#uses=1] 89 br i1 %C, label %retlbl, label %loop 90 91 loop: ; preds = %loop, %Top 92 %F = add i32 %A, %B ; <i32> [#uses=0] 93 %G = sub i32 %D, -4 ; <i32> [#uses=1] 94 %D.upgrd.1 = icmp sle i32 %G, 0 ; <i1> [#uses=1] 95 %E.upgrd.2 = xor i1 %D.upgrd.1, true ; <i1> [#uses=1] 96 br i1 %E.upgrd.2, label %loop, label %Top 97 98 retlbl: ; preds = %Top 99 ret void 100 } 101 102 103 ;; Test use of a boolean result in cast operations. 104 ;; Requires converting a condition code result into a 0/1 value in a reg. 105 ;; 106 define i32 @castbool(i32 %A, i32 %B) { 107 bb0: 108 %cond213 = icmp slt i32 %A, %B ; <i1> [#uses=1] 109 %cast110 = zext i1 %cond213 to i8 ; <i8> [#uses=1] 110 %cast109 = zext i8 %cast110 to i32 ; <i32> [#uses=1] 111 ret i32 %cast109 112 } 113 114 ;; Test use of a boolean result in arithmetic and logical operations. 115 ;; Requires converting a condition code result into a 0/1 value in a reg. 116 ;; 117 define i1 @boolexpr(i1 %b, i32 %N) { 118 %b2 = icmp sge i32 %N, 0 ; <i1> [#uses=1] 119 %b3 = and i1 %b, %b2 ; <i1> [#uses=1] 120 ret i1 %b3 121 } 122 123 ; Test branch on floating point comparison 124 ; 125 define void @testfloatbool(float %x, float %y) { 126 br label %Top 127 128 Top: ; preds = %Top, %0 129 %p = fadd float %x, %y ; <float> [#uses=1] 130 %z = fsub float %x, %y ; <float> [#uses=1] 131 %b = fcmp ole float %p, %z ; <i1> [#uses=2] 132 %c = xor i1 %b, true ; <i1> [#uses=0] 133 br i1 %b, label %Top, label %goon 134 135 goon: ; preds = %Top 136 ret void 137 } 138 139 140 ; Test cases where an LLVM instruction requires no machine 141 ; instructions (e.g., cast int* to long). But there are 2 cases: 142 ; 1. If the result register has only a single use and the use is in the 143 ; same basic block, the operand will be copy-propagated during 144 ; instruction selection. 145 ; 2. If the result register has multiple uses or is in a different 146 ; basic block, it cannot (or will not) be copy propagated during 147 ; instruction selection. It will generate a 148 ; copy instruction (add-with-0), but this copy should get coalesced 149 ; away by the register allocator. 150 ; 151 define i32 @checkForward(i32 %N, i32* %A) { 152 bb2: 153 %reg114 = shl i32 %N, 2 ; <i32> [#uses=1] 154 %cast115 = sext i32 %reg114 to i64 ; <i64> [#uses=1] 155 %cast116 = ptrtoint i32* %A to i64 ; <i64> [#uses=1] 156 %reg116 = add i64 %cast116, %cast115 ; <i64> [#uses=1] 157 %castPtr = inttoptr i64 %reg116 to i32* ; <i32*> [#uses=1] 158 %reg118 = load i32* %castPtr ; <i32> [#uses=1] 159 %cast117 = sext i32 %reg118 to i64 ; <i64> [#uses=2] 160 %reg159 = add i64 1234567, %cast117 ; <i64> [#uses=0] 161 %reg160 = add i64 7654321, %cast117 ; <i64> [#uses=0] 162 ret i32 0 163 } 164 165 166 ; Test case for unary NOT operation constructed from XOR. 167 ; 168 define void @checkNot(i1 %b, i32 %i) { 169 %notB = xor i1 %b, true ; <i1> [#uses=1] 170 %notI = xor i32 %i, -1 ; <i32> [#uses=2] 171 %F = icmp sge i32 %notI, 100 ; <i1> [#uses=1] 172 %J = add i32 %i, %i ; <i32> [#uses=1] 173 %andNotB = and i1 %F, %notB ; <i1> [#uses=0] 174 %andNotI = and i32 %J, %notI ; <i32> [#uses=0] 175 %notB2 = xor i1 true, %b ; <i1> [#uses=0] 176 %notI2 = xor i32 -1, %i ; <i32> [#uses=0] 177 ret void 178 } 179 180 ; Test case for folding getelementptr into a load/store 181 ; 182 define i32 @checkFoldGEP(%Domain* %D, i64 %idx) { 183 %reg841 = getelementptr %Domain* %D, i64 0, i32 1 ; <i32*> [#uses=1] 184 %reg820 = load i32* %reg841 ; <i32> [#uses=1] 185 ret i32 %reg820 186 } 187 188 ; Test case for scalarising a 1 element vselect 189 ; 190 define <1 x i32> @checkScalariseVSELECT(<1 x i32> %a, <1 x i32> %b) { 191 %cond = icmp uge <1 x i32> %a, %b 192 %s = select <1 x i1> %cond, <1 x i32> %a, <1 x i32> %b 193 ret <1 x i32> %s 194 } 195 196
