X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTarget%2FSparc%2FSparcCallingConv.td;h=dfaaabf344a3ad692d71967d7a1d5982bdea287d;hb=bcc0fa6a6430e8bba856f5d64fdd4f48b7b8d54d;hp=b38ac616dcf4654789b17150d3105bdbd48c9399;hpb=f37812e906a3abbdb8353e2eb9e8223ff9036b68;p=oota-llvm.git diff --git a/lib/Target/Sparc/SparcCallingConv.td b/lib/Target/Sparc/SparcCallingConv.td index b38ac616dcf..dfaaabf344a 100644 --- a/lib/Target/Sparc/SparcCallingConv.td +++ b/lib/Target/Sparc/SparcCallingConv.td @@ -12,27 +12,11 @@ //===----------------------------------------------------------------------===// //===----------------------------------------------------------------------===// -// Return Value Calling Conventions +// SPARC v8 32-bit. //===----------------------------------------------------------------------===// -// Sparc 32-bit C return-value convention. -def RetCC_Sparc32 : CallingConv<[ - CCIfType<[i32], CCAssignToReg<[I0, I1, I2, I3, I4, I5]>>, - CCIfType<[f32], CCAssignToReg<[F0, F1, F2, F3]>>, - CCIfType<[f64], CCAssignToReg<[D0, D1]>> -]>; - -// Sparc 64-bit C return-value convention. -def RetCC_Sparc64 : CallingConv<[ - CCIfType<[i32], CCPromoteToType>, - CCIfType<[i64], CCAssignToReg<[I0, I1, I2, I3, I4, I5]>>, - CCIfType<[f32], CCAssignToReg<[F0, F1, F2, F3]>>, - CCIfType<[f64], CCAssignToReg<[D0, D1]>> -]>; - -// Sparc 32-bit C Calling convention. def CC_Sparc32 : CallingConv<[ - //Custom assign SRet to [sp+64]. + // Custom assign SRet to [sp+64]. CCIfSRet>, // i32 f32 arguments get passed in integer registers if there is space. CCIfType<[i32, f32], CCAssignToReg<[I0, I1, I2, I3, I4, I5]>>, @@ -43,14 +27,113 @@ def CC_Sparc32 : CallingConv<[ CCAssignToStack<4, 4> ]>; -// Sparc 64-bit C Calling convention. +def RetCC_Sparc32 : CallingConv<[ + CCIfType<[i32], CCAssignToReg<[I0, I1, I2, I3, I4, I5]>>, + CCIfType<[f32], CCAssignToReg<[F0, F1, F2, F3]>>, + CCIfType<[f64], CCAssignToReg<[D0, D1]>> +]>; + + +//===----------------------------------------------------------------------===// +// SPARC v9 64-bit. +//===----------------------------------------------------------------------===// +// +// The 64-bit ABI conceptually assigns all function arguments to a parameter +// array starting at [%fp+BIAS+128] in the callee's stack frame. All arguments +// occupy a multiple of 8 bytes in the array. Integer arguments are extended to +// 64 bits by the caller. Floats are right-aligned in their 8-byte slot, the +// first 4 bytes in the slot are undefined. +// +// The integer registers %i0 to %i5 shadow the first 48 bytes of the parameter +// array at fixed offsets. Integer arguments are promoted to registers when +// possible. +// +// The floating point registers %f0 to %f31 shadow the first 128 bytes of the +// parameter array at fixed offsets. Float and double parameters are promoted +// to these registers when possible. +// +// Structs up to 16 bytes in size are passed by value. They are right-aligned +// in one or two 8-byte slots in the parameter array. Struct members are +// promoted to both floating point and integer registers when possible. A +// struct containing two floats would thus be passed in %f0 and %f1, while two +// float function arguments would occupy 8 bytes each, and be passed in %f1 and +// %f3. +// +// When a struct { int, float } is passed by value, the int goes in the high +// bits of an integer register while the float goes in a floating point +// register. +// +// The difference is encoded in LLVM IR using the inreg atttribute on function +// arguments: +// +// C: void f(float, float); +// IR: declare void f(float %f1, float %f3) +// +// C: void f(struct { float f0, f1; }); +// IR: declare void f(float inreg %f0, float inreg %f1) +// +// C: void f(int, float); +// IR: declare void f(int signext %i0, float %f3) +// +// C: void f(struct { int i0high; float f1; }); +// IR: declare void f(i32 inreg %i0high, float inreg %f1) +// +// Two ints in a struct are simply coerced to i64: +// +// C: void f(struct { int i0high, i0low; }); +// IR: declare void f(i64 %i0.coerced) +// +// The frontend and backend divide the task of producing ABI compliant code for +// C functions. The C frontend will: +// +// - Annotate integer arguments with zeroext or signext attributes. +// +// - Split structs into one or two 64-bit sized chunks, or 32-bit chunks with +// inreg attributes. +// +// - Pass structs larger than 16 bytes indirectly with an explicit pointer +// argument. The byval attribute is not used. +// +// The backend will: +// +// - Assign all arguments to 64-bit aligned stack slots, 32-bits for inreg. +// +// - Promote to integer or floating point registers depending on type. +// +// Function return values are passed exactly like function arguments, except a +// struct up to 32 bytes in size can be returned in registers. + +// Function arguments AND most return values. def CC_Sparc64 : CallingConv<[ + // The frontend uses the inreg flag to indicate i32 and float arguments from + // structs. These arguments are not promoted to 64 bits, but they can still + // be assigned to integer and float registers. + CCIfInReg>>, + // All integers are promoted to i64 by the caller. CCIfType<[i32], CCPromoteToType>, - // Integer arguments get passed in integer registers if there is space. - CCIfType<[i64], CCAssignToReg<[I0, I1, I2, I3, I4, I5]>>, - // FIXME: Floating point arguments. - // Alternatively, they are assigned to the stack in 8-byte aligned units. - CCAssignToStack<8, 8> + // Custom assignment is required because stack space is reserved for all + // arguments whether they are passed in registers or not. + CCCustom<"CC_Sparc64_Full"> ]>; + +def RetCC_Sparc64 : CallingConv<[ + // A single f32 return value always goes in %f0. The ABI doesn't specify what + // happens to multiple f32 return values outside a struct. + CCIfType<[f32], CCCustom<"CC_Sparc64_Half">>, + + // Otherwise, return values are passed exactly like arguments. + CCDelegateTo +]>; + +// Callee-saved registers are handled by the register window mechanism. +def CSR : CalleeSavedRegs<(add)> { + let OtherPreserved = (add (sequence "I%u", 0, 7), + (sequence "L%u", 0, 7)); +} + +// Callee-saved registers for calls with ReturnsTwice attribute. +def RTCSR : CalleeSavedRegs<(add)> { + let OtherPreserved = (add I6, I7); +}