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Fixed implementation of RV64 so that remaining riscv-test pass

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This commit is contained in:
eyck
2019-01-10 10:35:20 +00:00
parent d5d236bf10
commit f69b529cab
27 changed files with 19993 additions and 8967 deletions
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219
riscv/gen_input/RV32F.core_desc
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@ -30,10 +30,13 @@ InsructionSet RV32F extends RV32IBase{
encoding: rs3[4:0] | b00 | rs2[4:0] | rs1[4:0] | rm[2:0] | rd[4:0] | b1000011;
args_disass:"x{rd}, f{rs1}, f{rs2}, f{rs3}";
//F[rd]f<= F[rs1]f * F[rs2]f + F[rs3]f;
val res[32] <= fdispatch_fmadd_s(F[rs1]{32}, F[rs2]{32}, F[rs3]{32}, zext(0, 32), choose(rm<7, rm{8}, FCSR{8}));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fmadd_s(F[rs1], F[rs2], F[rs3], zext(0, 32), choose(rm<7, rm{8}, FCSR{8}));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val frs3[32] <= fdispatch_unbox_s(F[rs3]);
val res[32] <= fdispatch_fmadd_s(frs1, frs2, frs3, zext(0, 32), choose(rm<7, rm{8}, FCSR{8}));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -44,10 +47,13 @@ InsructionSet RV32F extends RV32IBase{
encoding: rs3[4:0] | b00 | rs2[4:0] | rs1[4:0] | rm[2:0] | rd[4:0] | b1000111;
args_disass:"x{rd}, f{rs1}, f{rs2}, f{rs3}";
//F[rd]f<=F[rs1]f * F[rs2]f - F[rs3]f;
val res[32] <= fdispatch_fmadd_s(F[rs1]{32}, F[rs2]{32}, F[rs3]{32}, zext(1, 32), choose(rm<7, rm{8}, FCSR{8}));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fmadd_s(F[rs1], F[rs2], F[rs3], zext(1, 32), choose(rm<7, rm{8}, FCSR{8}));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val frs3[32] <= fdispatch_unbox_s(F[rs3]);
val res[32] <= fdispatch_fmadd_s(frs1, frs2, frs3, zext(1, 32), choose(rm<7, rm{8}, FCSR{8}));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -58,10 +64,13 @@ InsructionSet RV32F extends RV32IBase{
encoding: rs3[4:0] | b00 | rs2[4:0] | rs1[4:0] | rm[2:0] | rd[4:0] | b1001111;
args_disass:"x{rd}, f{rs1}, f{rs2}, f{rs3}";
//F[rd]f<=-F[rs1]f * F[rs2]f + F[rs3]f;
val res[32] <= fdispatch_fmadd_s(F[rs1]{32}, F[rs2]{32}, F[rs3]{32}, zext(2, 32), choose(rm<7, rm{8}, FCSR{8}));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fmadd_s(F[rs1], F[rs2], F[rs3], zext(2, 32), choose(rm<7, rm{8}, FCSR{8}));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val frs3[32] <= fdispatch_unbox_s(F[rs3]);
val res[32] <= fdispatch_fmadd_s(frs1, frs2, frs3, zext(2, 32), choose(rm<7, rm{8}, FCSR{8}));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -72,10 +81,13 @@ InsructionSet RV32F extends RV32IBase{
encoding: rs3[4:0] | b00 | rs2[4:0] | rs1[4:0] | rm[2:0] | rd[4:0] | b1001011;
args_disass:"x{rd}, f{rs1}, f{rs2}, f{rs3}";
//F[rd]f<=-F[rs1]f * F[rs2]f - F[rs3]f;
val res[32] <= fdispatch_fmadd_s(F[rs1]{32}, F[rs2]{32}, F[rs3]{32}, zext(3, 32), choose(rm<7, rm{8}, FCSR{8}));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fmadd_s(F[rs1], F[rs2], F[rs3], zext(3, 32), choose(rm<7, rm{8}, FCSR{8}));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val frs3[32] <= fdispatch_unbox_s(F[rs3]);
val res[32] <= fdispatch_fmadd_s(frs1, frs2, frs3, zext(3, 32), choose(rm<7, rm{8}, FCSR{8}));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -86,10 +98,12 @@ InsructionSet RV32F extends RV32IBase{
encoding: b0000000 | rs2[4:0] | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}, f{rs2}";
// F[rd]f <= F[rs1]f + F[rs2]f;
val res[32] <= fdispatch_fadd_s(F[rs1]{32}, F[rs2]{32}, choose(rm<7, rm{8}, FCSR{8}));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fadd_s(F[rs1], F[rs2], choose(rm<7, rm{8}, FCSR{8}));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val res[32] <= fdispatch_fadd_s(frs1, frs2, choose(rm<7, rm{8}, FCSR{8}));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -100,10 +114,12 @@ InsructionSet RV32F extends RV32IBase{
encoding: b0000100 | rs2[4:0] | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}, f{rs2}";
// F[rd]f <= F[rs1]f - F[rs2]f;
val res[32] <= fdispatch_fsub_s(F[rs1]{32}, F[rs2]{32}, choose(rm<7, rm{8}, FCSR{8}));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fsub_s(F[rs1], F[rs2], choose(rm<7, rm{8}, FCSR{8}));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val res[32] <= fdispatch_fsub_s(frs1, frs2, choose(rm<7, rm{8}, FCSR{8}));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -114,10 +130,12 @@ InsructionSet RV32F extends RV32IBase{
encoding: b0001000 | rs2[4:0] | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}, f{rs2}";
// F[rd]f <= F[rs1]f * F[rs2]f;
val res[32] <= fdispatch_fmul_s(F[rs1]{32}, F[rs2]{32}, choose(rm<7, rm{8}, FCSR{8}));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fmul_s(F[rs1], F[rs2], choose(rm<7, rm{8}, FCSR{8}));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val res[32] <= fdispatch_fmul_s(frs1, frs2, choose(rm<7, rm{8}, FCSR{8}));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -128,10 +146,12 @@ InsructionSet RV32F extends RV32IBase{
encoding: b0001100 | rs2[4:0] | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}, f{rs2}";
// F[rd]f <= F[rs1]f / F[rs2]f;
val res[32] <= fdispatch_fdiv_s(F[rs1]{32}, F[rs2]{32}, choose(rm<7, rm{8}, FCSR{8}));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fdiv_s(F[rs1], F[rs2], choose(rm<7, rm{8}, FCSR{8}));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val res[32] <= fdispatch_fdiv_s(frs1, frs2, choose(rm<7, rm{8}, FCSR{8}));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -142,10 +162,11 @@ InsructionSet RV32F extends RV32IBase{
encoding: b0101100 | b00000 | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}";
//F[rd]f<=sqrt(F[rs1]f);
val res[32] <= fdispatch_fsqrt_s(F[rs1]{32}, choose(rm<7, rm{8}, FCSR{8}));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fsqrt_s(F[rs1], choose(rm<7, rm{8}, FCSR{8}));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val res[32] <= fdispatch_fsqrt_s(frs1, choose(rm<7, rm{8}, FCSR{8}));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -155,10 +176,12 @@ InsructionSet RV32F extends RV32IBase{
FSGNJ.S {
encoding: b0010000 | rs2[4:0] | rs1[4:0] | b000 | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}, f{rs2}";
val res[32] <= (F[rs1]{32} & 0x7fffffff) | (F[rs2]{32} & 0x80000000);
if(FLEN==32)
F[rd] <= res;
F[rd] <= (F[rs1] & 0x7fffffff) | (F[rs2] & 0x80000000);
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val res[32] <= (frs1 & 0x7fffffff) | (frs2 & 0x80000000);
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -166,10 +189,12 @@ InsructionSet RV32F extends RV32IBase{
FSGNJN.S {
encoding: b0010000 | rs2[4:0] | rs1[4:0] | b001 | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}, f{rs2}";
val res[32] <= (F[rs1]{32} & 0x7fffffff) | (~F[rs2]{32} & 0x80000000);
if(FLEN==32)
F[rd] <= res;
F[rd] <= (F[rs1] & 0x7fffffff) | (~F[rs2] & 0x80000000);
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val res[32] <= (frs1 & 0x7fffffff) | (~frs2 & 0x80000000);
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -177,10 +202,12 @@ InsructionSet RV32F extends RV32IBase{
FSGNJX.S {
encoding: b0010000 | rs2[4:0] | rs1[4:0] | b010 | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}, f{rs2}";
val res[32] <= F[rs1]{32} ^ (F[rs2]{32} & 0x80000000);
if(FLEN==32)
F[rd] <= res;
F[rd] <= F[rs1] ^ (F[rs2] & 0x80000000);
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val res[32] <= frs1 ^ (frs2 & 0x80000000);
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -189,10 +216,12 @@ InsructionSet RV32F extends RV32IBase{
encoding: b0010100 | rs2[4:0] | rs1[4:0] | b000 | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}, f{rs2}";
//F[rd]f<= choose(F[rs1]f<F[rs2]f, F[rs1]f, F[rs2]f);
val res[32] <= fdispatch_fsel_s(F[rs1]{32}, F[rs2]{32}, zext(0, 32));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fsel_s(F[rs1], F[rs2], zext(0, 32));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val res[32] <= fdispatch_fsel_s(frs1, frs2, zext(0, 32));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -203,10 +232,12 @@ InsructionSet RV32F extends RV32IBase{
encoding: b0010100 | rs2[4:0] | rs1[4:0] | b001 | rd[4:0] | b1010011;
args_disass:"f{rd}, f{rs1}, f{rs2}";
//F[rd]f<= choose(F[rs1]f>F[rs2]f, F[rs1]f, F[rs2]f);
val res[32] <= fdispatch_fsel_s(F[rs1]{32}, F[rs2]{32}, zext(1, 32));
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fsel_s(F[rs1], F[rs2], zext(1, 32));
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
val res[32] <= fdispatch_fsel_s(frs1, frs2, zext(1, 32));
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
@ -215,59 +246,142 @@ InsructionSet RV32F extends RV32IBase{
}
FCVT.W.S {
encoding: b1100000 | b00000 | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"x{rd}, f{rs1}";
X[rd]<= sext(fdispatch_fcvt_s(F[rs1]{32}, zext(0, 32), rm{8}), XLEN);
args_disass:"{name(rd)}, f{rs1}";
if(FLEN==32)
X[rd] <= sext(fdispatch_fcvt_s(F[rs1], zext(0, 32), rm{8}), XLEN);
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
X[rd]<= sext(fdispatch_fcvt_s(frs1, zext(0, 32), rm{8}), XLEN);
}
val flags[32] <= fdispatch_fget_flags();
FCSR <= (FCSR & ~FFLAG_MASK) + flags{5};
}
FCVT.WU.S {
encoding: b1100000 | b00001 | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"x{rd}, f{rs1}";
X[rd]<= zext(fdispatch_fcvt_s(F[rs1]{32}, zext(1, 32), rm{8}), XLEN);
args_disass:"{name(rd)}, f{rs1}";
//FIXME: according to the spec it should be zero-extended not sign extended
if(FLEN==32)
X[rd]<= sext(fdispatch_fcvt_s(F[rs1], zext(1, 32), rm{8}), XLEN);
else { // NaN boxing
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
X[rd]<= sext(fdispatch_fcvt_s(frs1, zext(1, 32), rm{8}), XLEN);
}
val flags[32] <= fdispatch_fget_flags();
FCSR <= (FCSR & ~FFLAG_MASK) + flags{5};
}
FEQ.S {
encoding: b1010000 | rs2[4:0] | rs1[4:0] | b010 | rd[4:0] | b1010011;
args_disass:"x{rd}, f{rs1}, f{rs2}";
X[rd]<=fdispatch_fcmp_s(F[rs1]{32}, F[rs2]{32}, zext(0, 32));
args_disass:"{name(rd)}, f{rs1}, f{rs2}";
if(FLEN==32)
X[rd]<=zext(fdispatch_fcmp_s(F[rs1], F[rs2], zext(0, 32)));
else {
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
X[rd]<=zext(fdispatch_fcmp_s(frs1, frs2, zext(0, 32)));
}
val flags[32] <= fdispatch_fget_flags();
FCSR <= (FCSR & ~FFLAG_MASK) + flags{5};
}
FLT.S {
encoding: b1010000 | rs2[4:0] | rs1[4:0] | b001 | rd[4:0] | b1010011;
args_disass:"x{rd}, f{rs1}, f{rs2}";
args_disass:"{name(rd)}, f{rs1}, f{rs2}";
if(FLEN==32)
X[rd]<=zext(fdispatch_fcmp_s(F[rs1], F[rs2], zext(2, 32)));
else {
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
X[rd]<=zext(fdispatch_fcmp_s(frs1, frs2, zext(2, 32)));
}
X[rd]<=fdispatch_fcmp_s(F[rs1]{32}, F[rs2]{32}, zext(2, 32));
val flags[32] <= fdispatch_fget_flags();
FCSR <= (FCSR & ~FFLAG_MASK) + flags{5};
}
FLE.S {
encoding: b1010000 | rs2[4:0] | rs1[4:0] | b000 | rd[4:0] | b1010011;
args_disass:"x{rd}, f{rs1}, f{rs2}";
X[rd]<=fdispatch_fcmp_s(F[rs1]{32}, F[rs2]{32}, zext(1, 32));
args_disass:"{name(rd)}, f{rs1}, f{rs2}";
if(FLEN==32)
X[rd]<=zext(fdispatch_fcmp_s(F[rs1], F[rs2], zext(1, 32)));
else {
val frs1[32] <= fdispatch_unbox_s(F[rs1]);
val frs2[32] <= fdispatch_unbox_s(F[rs2]);
X[rd]<=zext(fdispatch_fcmp_s(frs1, frs2, zext(1, 32)));
}
val flags[32] <= fdispatch_fget_flags();
FCSR <= (FCSR & ~FFLAG_MASK) + flags{5};
}
FCLASS.S {
encoding: b1110000 | b00000 | rs1[4:0] | b001 | rd[4:0] | b1010011;
args_disass:"x{rd}, f{rs1}";
X[rd]<=fdispatch_fclass_s(F[rs1]{32});
args_disass:"{name(rd)}, f{rs1}";
X[rd]<=fdispatch_fclass_s(fdispatch_unbox_s(F[rs1]));
}
FCVT.S.W {
encoding: b1101000 | b00000 | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"f{rd}, x{rs1}";
val res[32] <= fdispatch_fcvt_s(X[rs1]{32}, zext(2, 32), rm{8});
args_disass:"f{rd}, {name(rs1)}";
if(FLEN==32)
F[rd] <= res;
F[rd] <= fdispatch_fcvt_s(X[rs1]{32}, zext(2, 32), rm{8});
else { // NaN boxing
val res[32] <= fdispatch_fcvt_s(X[rs1]{32}, zext(2, 32), rm{8});
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
}
FCVT.S.WU {
encoding: b1101000 | b00001 | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"f{rd}, {name(rs1)}";
if(FLEN==32)
F[rd] <=fdispatch_fcvt_s(X[rs1]{32}, zext(3,32), rm{8});
else { // NaN boxing
val res[32] <=fdispatch_fcvt_s(X[rs1]{32}, zext(3,32), rm{8});
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(res, FLEN);
}
}
FMV.X.W {
encoding: b1110000 | b00000 | rs1[4:0] | b000 | rd[4:0] | b1010011;
args_disass:"{name(rd)}, f{rs1}";
X[rd]<=sext(F[rs1]{32});
}
FMV.W.X {
encoding: b1111000 | b00000 | rs1[4:0] | b000 | rd[4:0] | b1010011;
args_disass:"f{rd}, {name(rs1)}";
if(FLEN==32)
F[rd] <= X[rs1]{32};
else { // NaN boxing
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(X[rs1]{32}, FLEN);
}
}
}
}
InsructionSet RV64F extends RV32F{
constants {
FLEN, FFLAG_MASK := 0x1f
}
registers {
[31:0] F[FLEN], FCSR[32]
}
instructions{
FCVT.L.S { // fp to 64bit signed integer
encoding: b1100000 | b00010 | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"x{rd}, f{rs1}";
val res[64] <= fdispatch_fcvt_32_64(fdispatch_unbox_s(F[rs1]), zext(0, 32), rm{8});
X[rd]<= sext(res);
val flags[32] <= fdispatch_fget_flags();
FCSR <= (FCSR & ~FFLAG_MASK) + flags{5};
}
FCVT.LU.S { // fp to 64bit unsigned integer
encoding: b1100000 | b00011 | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"x{rd}, f{rs1}";
val res[64] <= fdispatch_fcvt_32_64(fdispatch_unbox_s(F[rs1]), zext(1, 32), rm{8});
X[rd]<= zext(res);
val flags[32] <= fdispatch_fget_flags();
FCSR <= (FCSR & ~FFLAG_MASK) + flags{5};
}
FCVT.S.L { // 64bit signed int to to fp
encoding: b1101000 | b00010 | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"f{rd}, x{rs1}";
val res[32] <=fdispatch_fcvt_s(X[rs1]{32}, zext(3,32), rm{8});
val res[32] <= fdispatch_fcvt_64_32(X[rs1], zext(2, 32));
if(FLEN==32)
F[rd] <= res;
else { // NaN boxing
@ -275,20 +389,17 @@ InsructionSet RV32F extends RV32IBase{
F[rd] <= (upper<<32) | zext(res, FLEN);
}
}
FMV.X.W {
encoding: b1110000 | b00000 | rs1[4:0] | b000 | rd[4:0] | b1010011;
args_disass:"x{rd}, f{rs1}";
X[rd]<=sext(F[rs1]{32});
}
FMV.W.X {
encoding: b1111000 | b00000 | rs1[4:0] | b000 | rd[4:0] | b1010011;
FCVT.S.LU { // 64bit unsigned int to to fp
encoding: b1101000 | b00011 | rs1[4:0] | rm[2:0] | rd[4:0] | b1010011;
args_disass:"f{rd}, x{rs1}";
val res[32] <=fdispatch_fcvt_64_32(X[rs1], zext(3,32));
if(FLEN==32)
F[rd] <= X[rs1];
F[rd] <= res;
else { // NaN boxing
val upper[FLEN] <= -1;
F[rd] <= (upper<<32) | zext(X[rs1], FLEN);
F[rd] <= (upper<<32) | zext(res, FLEN);
}
}
}
}
}
}