1 //=- SystemZCallingConv.td - Calling conventions for SystemZ -*- tablegen -*-=// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // This describes the calling conventions for the SystemZ ABI. 10 //===----------------------------------------------------------------------===// 11 12 class CCIfExtend<CCAction A> 13 : CCIf<"ArgFlags.isSExt() || ArgFlags.isZExt()", A>; 14 15 class CCIfSubtarget<string F, CCAction A> 16 : CCIf<!strconcat("static_cast<const SystemZSubtarget&>" 17 "(State.getMachineFunction().getSubtarget()).", F), 18 A>; 19 20 // Match if this specific argument is a fixed (i.e. named) argument. 21 class CCIfFixed<CCAction A> 22 : CCIf<"static_cast<SystemZCCState *>(&State)->IsFixed(ValNo)", A>; 23 24 // Match if this specific argument was widened from a short vector type. 25 class CCIfShortVector<CCAction A> 26 : CCIf<"static_cast<SystemZCCState *>(&State)->IsShortVector(ValNo)", A>; 27 28 29 //===----------------------------------------------------------------------===// 30 // z/Linux return value calling convention 31 //===----------------------------------------------------------------------===// 32 def RetCC_SystemZ : CallingConv<[ 33 // Promote i32 to i64 if it has an explicit extension type. 34 CCIfType<[i32], CCIfExtend<CCPromoteToType<i64>>>, 35 36 // ABI-compliant code returns 64-bit integers in R2. Make the other 37 // call-clobbered argument registers available for code that doesn't 38 // care about the ABI. (R6 is an argument register too, but is 39 // call-saved and therefore not suitable for return values.) 40 CCIfType<[i32], CCAssignToReg<[R2L, R3L, R4L, R5L]>>, 41 CCIfType<[i64], CCAssignToReg<[R2D, R3D, R4D, R5D]>>, 42 43 // ABI-complaint code returns float and double in F0. Make the 44 // other floating-point argument registers available for code that 45 // doesn't care about the ABI. All floating-point argument registers 46 // are call-clobbered, so we can use all of them here. 47 CCIfType<[f32], CCAssignToReg<[F0S, F2S, F4S, F6S]>>, 48 CCIfType<[f64], CCAssignToReg<[F0D, F2D, F4D, F6D]>>, 49 50 // Similarly for vectors, with V24 being the ABI-compliant choice. 51 // Sub-128 vectors are returned in the same way, but they're widened 52 // to one of these types during type legalization. 53 CCIfSubtarget<"hasVector()", 54 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], 55 CCAssignToReg<[V24, V26, V28, V30, V25, V27, V29, V31]>>> 56 ]>; 57 58 //===----------------------------------------------------------------------===// 59 // z/Linux argument calling conventions 60 //===----------------------------------------------------------------------===// 61 def CC_SystemZ : CallingConv<[ 62 // Promote i32 to i64 if it has an explicit extension type. 63 // The convention is that true integer arguments that are smaller 64 // than 64 bits should be marked as extended, but structures that 65 // are smaller than 64 bits shouldn't. 66 CCIfType<[i32], CCIfExtend<CCPromoteToType<i64>>>, 67 68 // Force long double values to the stack and pass i64 pointers to them. 69 CCIfType<[f128], CCPassIndirect<i64>>, 70 71 // The first 5 integer arguments are passed in R2-R6. Note that R6 72 // is call-saved. 73 CCIfType<[i32], CCAssignToReg<[R2L, R3L, R4L, R5L, R6L]>>, 74 CCIfType<[i64], CCAssignToReg<[R2D, R3D, R4D, R5D, R6D]>>, 75 76 // The first 4 float and double arguments are passed in even registers F0-F6. 77 CCIfType<[f32], CCAssignToReg<[F0S, F2S, F4S, F6S]>>, 78 CCIfType<[f64], CCAssignToReg<[F0D, F2D, F4D, F6D]>>, 79 80 // The first 8 named vector arguments are passed in V24-V31. Sub-128 vectors 81 // are passed in the same way, but they're widened to one of these types 82 // during type legalization. 83 CCIfSubtarget<"hasVector()", 84 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], 85 CCIfFixed<CCAssignToReg<[V24, V26, V28, V30, 86 V25, V27, V29, V31]>>>>, 87 88 // However, sub-128 vectors which need to go on the stack occupy just a 89 // single 8-byte-aligned 8-byte stack slot. Pass as i64. 90 CCIfSubtarget<"hasVector()", 91 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], 92 CCIfShortVector<CCBitConvertToType<i64>>>>, 93 94 // Other vector arguments are passed in 8-byte-aligned 16-byte stack slots. 95 CCIfSubtarget<"hasVector()", 96 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], 97 CCAssignToStack<16, 8>>>, 98 99 // Other arguments are passed in 8-byte-aligned 8-byte stack slots. 100 CCIfType<[i32, i64, f32, f64], CCAssignToStack<8, 8>> 101 ]>; 102 103 //===----------------------------------------------------------------------===// 104 // z/Linux callee-saved registers 105 //===----------------------------------------------------------------------===// 106 def CSR_SystemZ : CalleeSavedRegs<(add (sequence "R%dD", 6, 15), 107 (sequence "F%dD", 8, 15))>; 108
