Files
wasmtime/cranelift/codegen/meta/src/isa/riscv/recipes.rs
Peter Huene 9f506692c2 Fix clippy warnings.
This commit fixes the current set of (stable) clippy warnings in the repo.
2019-10-24 17:20:12 -07:00

279 lines
9.2 KiB
Rust

use std::collections::HashMap;
use crate::cdsl::instructions::InstructionPredicate;
use crate::cdsl::recipes::{EncodingRecipeBuilder, EncodingRecipeNumber, Recipes, Stack};
use crate::cdsl::regs::IsaRegs;
use crate::shared::Definitions as SharedDefinitions;
/// An helper to create recipes and use them when defining the RISCV encodings.
pub(crate) struct RecipeGroup {
/// The actualy list of recipes explicitly created in this file.
pub recipes: Recipes,
/// Provides fast lookup from a name to an encoding recipe.
name_to_recipe: HashMap<String, EncodingRecipeNumber>,
}
impl RecipeGroup {
fn new() -> Self {
Self {
recipes: Recipes::new(),
name_to_recipe: HashMap::new(),
}
}
fn push(&mut self, builder: EncodingRecipeBuilder) {
assert!(
self.name_to_recipe.get(&builder.name).is_none(),
format!("riscv recipe '{}' created twice", builder.name)
);
let name = builder.name.clone();
let number = self.recipes.push(builder.build());
self.name_to_recipe.insert(name, number);
}
pub fn by_name(&self, name: &str) -> EncodingRecipeNumber {
*self
.name_to_recipe
.get(name)
.unwrap_or_else(|| panic!("unknown riscv recipe name {}", name))
}
pub fn collect(self) -> Recipes {
self.recipes
}
}
pub(crate) fn define(shared_defs: &SharedDefinitions, regs: &IsaRegs) -> RecipeGroup {
let formats = &shared_defs.formats;
// Register classes shorthands.
let gpr = regs.class_by_name("GPR");
// Definitions.
let mut recipes = RecipeGroup::new();
// R-type 32-bit instructions: These are mostly binary arithmetic instructions.
// The encbits are `opcode[6:2] | (funct3 << 5) | (funct7 << 8)
recipes.push(
EncodingRecipeBuilder::new("R", &formats.binary, 4)
.operands_in(vec![gpr, gpr])
.operands_out(vec![gpr])
.emit("put_r(bits, in_reg0, in_reg1, out_reg0, sink);"),
);
// R-type with an immediate shift amount instead of rs2.
recipes.push(
EncodingRecipeBuilder::new("Rshamt", &formats.binary_imm, 4)
.operands_in(vec![gpr])
.operands_out(vec![gpr])
.emit("put_rshamt(bits, in_reg0, imm.into(), out_reg0, sink);"),
);
// R-type encoding of an integer comparison.
recipes.push(
EncodingRecipeBuilder::new("Ricmp", &formats.int_compare, 4)
.operands_in(vec![gpr, gpr])
.operands_out(vec![gpr])
.emit("put_r(bits, in_reg0, in_reg1, out_reg0, sink);"),
);
recipes.push(
EncodingRecipeBuilder::new("Ii", &formats.binary_imm, 4)
.operands_in(vec![gpr])
.operands_out(vec![gpr])
.inst_predicate(InstructionPredicate::new_is_signed_int(
&*formats.binary_imm,
"imm",
12,
0,
))
.emit("put_i(bits, in_reg0, imm.into(), out_reg0, sink);"),
);
// I-type instruction with a hardcoded %x0 rs1.
recipes.push(
EncodingRecipeBuilder::new("Iz", &formats.unary_imm, 4)
.operands_out(vec![gpr])
.inst_predicate(InstructionPredicate::new_is_signed_int(
&formats.unary_imm,
"imm",
12,
0,
))
.emit("put_i(bits, 0, imm.into(), out_reg0, sink);"),
);
// I-type encoding of an integer comparison.
recipes.push(
EncodingRecipeBuilder::new("Iicmp", &formats.int_compare_imm, 4)
.operands_in(vec![gpr])
.operands_out(vec![gpr])
.inst_predicate(InstructionPredicate::new_is_signed_int(
&formats.int_compare_imm,
"imm",
12,
0,
))
.emit("put_i(bits, in_reg0, imm.into(), out_reg0, sink);"),
);
// I-type encoding for `jalr` as a return instruction. We won't use the immediate offset. The
// variable return values are not encoded.
recipes.push(
EncodingRecipeBuilder::new("Iret", &formats.multiary, 4).emit(
r#"
// Return instructions are always a jalr to %x1.
// The return address is provided as a special-purpose link argument.
put_i(
bits,
1, // rs1 = %x1
0, // no offset.
0, // rd = %x0: no address written.
sink,
);
"#,
),
);
// I-type encoding for `jalr` as a call_indirect.
recipes.push(
EncodingRecipeBuilder::new("Icall", &formats.call_indirect, 4)
.operands_in(vec![gpr])
.emit(
r#"
// call_indirect instructions are jalr with rd=%x1.
put_i(
bits,
in_reg0,
0, // no offset.
1, // rd = %x1: link register.
sink,
);
"#,
),
);
// Copy of a GPR is implemented as addi x, 0.
recipes.push(
EncodingRecipeBuilder::new("Icopy", &formats.unary, 4)
.operands_in(vec![gpr])
.operands_out(vec![gpr])
.emit("put_i(bits, in_reg0, 0, out_reg0, sink);"),
);
// Same for a GPR regmove.
recipes.push(
EncodingRecipeBuilder::new("Irmov", &formats.reg_move, 4)
.operands_in(vec![gpr])
.emit("put_i(bits, src, 0, dst, sink);"),
);
// Same for copy-to-SSA -- GPR regmove.
recipes.push(
EncodingRecipeBuilder::new("copytossa", &formats.copy_to_ssa, 4)
// No operands_in to mention, because a source register is specified directly.
.operands_out(vec![gpr])
.emit("put_i(bits, src, 0, out_reg0, sink);"),
);
// U-type instructions have a 20-bit immediate that targets bits 12-31.
recipes.push(
EncodingRecipeBuilder::new("U", &formats.unary_imm, 4)
.operands_out(vec![gpr])
.inst_predicate(InstructionPredicate::new_is_signed_int(
&formats.unary_imm,
"imm",
32,
12,
))
.emit("put_u(bits, imm.into(), out_reg0, sink);"),
);
// UJ-type unconditional branch instructions.
recipes.push(
EncodingRecipeBuilder::new("UJ", &formats.jump, 4)
.branch_range((0, 21))
.emit(
r#"
let dest = i64::from(func.offsets[destination]);
let disp = dest - i64::from(sink.offset());
put_uj(bits, disp, 0, sink);
"#,
),
);
recipes.push(EncodingRecipeBuilder::new("UJcall", &formats.call, 4).emit(
r#"
sink.reloc_external(Reloc::RiscvCall,
&func.dfg.ext_funcs[func_ref].name,
0);
// rd=%x1 is the standard link register.
put_uj(bits, 0, 1, sink);
"#,
));
// SB-type branch instructions.
recipes.push(
EncodingRecipeBuilder::new("SB", &formats.branch_icmp, 4)
.operands_in(vec![gpr, gpr])
.branch_range((0, 13))
.emit(
r#"
let dest = i64::from(func.offsets[destination]);
let disp = dest - i64::from(sink.offset());
put_sb(bits, disp, in_reg0, in_reg1, sink);
"#,
),
);
// SB-type branch instruction with rs2 fixed to zero.
recipes.push(
EncodingRecipeBuilder::new("SBzero", &formats.branch, 4)
.operands_in(vec![gpr])
.branch_range((0, 13))
.emit(
r#"
let dest = i64::from(func.offsets[destination]);
let disp = dest - i64::from(sink.offset());
put_sb(bits, disp, in_reg0, 0, sink);
"#,
),
);
// Spill of a GPR.
recipes.push(
EncodingRecipeBuilder::new("GPsp", &formats.unary, 4)
.operands_in(vec![gpr])
.operands_out(vec![Stack::new(gpr)])
.emit("unimplemented!();"),
);
// Fill of a GPR.
recipes.push(
EncodingRecipeBuilder::new("GPfi", &formats.unary, 4)
.operands_in(vec![Stack::new(gpr)])
.operands_out(vec![gpr])
.emit("unimplemented!();"),
);
// Stack-slot to same stack-slot copy, which is guaranteed to turn into a no-op.
recipes.push(
EncodingRecipeBuilder::new("stacknull", &formats.unary, 0)
.operands_in(vec![Stack::new(gpr)])
.operands_out(vec![Stack::new(gpr)])
.emit(""),
);
// No-op fills, created by late-stage redundant-fill removal.
recipes.push(
EncodingRecipeBuilder::new("fillnull", &formats.unary, 0)
.operands_in(vec![Stack::new(gpr)])
.operands_out(vec![gpr])
.clobbers_flags(false)
.emit(""),
);
recipes
}