cranelift: Parse iconst according to its type

Modifies the parser for textual CLIF so that V in `iconst.T V` is
parsed according to T.

Before this commit, something like `iconst.i32 0xffff_ffff_ffff` was
valid because all `iconst` were parsed the same as an
`iconst.i64`. Now the above example will throw an error.

Also, a negative immediate as in `iconst.iN -X` is now converted to
`2^N - X`.

This commit also fixes some broken tests.

cranelift/codegen/src/legalizer/mod.rs

@@ -16,7 +16,7 @@
 use crate::cursor::{Cursor, FuncCursor};
 use crate::flowgraph::ControlFlowGraph;
 use crate::ir::immediates::Imm64;
-use crate::ir::types::{I128, I64};
+use crate::ir::types::{self, I128, I64};
 use crate::ir::{self, InstBuilder, InstructionData, MemFlags, Value};
 use crate::isa::TargetIsa;
 use crate::trace;
@@ -38,7 +38,17 @@ fn imm_const(pos: &mut FuncCursor, arg: Value, imm: Imm64, is_signed: bool) -> V
             let imm = pos.ins().iconst(I64, imm);
             pos.ins().uextend(I128, imm)
         }
-        _ => pos.ins().iconst(ty.lane_type(), imm),
+        _ => {
+            let bits = imm.bits();
+            let unsigned = match ty.lane_type() {
+                types::I8 => bits as u8 as i64,
+                types::I16 => bits as u16 as i64,
+                types::I32 => bits as u32 as i64,
+                types::I64 => bits,
+                _ => unreachable!(),
+            };
+            pos.ins().iconst(ty.lane_type(), unsigned)
+        }
     }
 }
 

cranelift/codegen/src/write.rs

@@ -5,7 +5,9 @@
 
 use crate::entity::SecondaryMap;
 use crate::ir::entities::AnyEntity;
+use crate::ir::types;
 use crate::ir::{Block, DataFlowGraph, Function, Inst, SigRef, Type, Value, ValueDef};
+use crate::opts::Imm64;
 use crate::packed_option::ReservedValue;
 use alloc::string::{String, ToString};
 use alloc::vec::Vec;
@@ -380,7 +382,16 @@ pub fn write_operands(w: &mut dyn Write, dfg: &DataFlowGraph, inst: Inst) -> fmt
         LoadNoOffset { flags, arg, .. } => write!(w, "{} {}", flags, arg),
         StoreNoOffset { flags, args, .. } => write!(w, "{} {}, {}", flags, args[0], args[1]),
         Unary { arg, .. } => write!(w, " {}", arg),
-        UnaryImm { imm, .. } => write!(w, " {}", imm),
+        UnaryImm { imm, .. } => {
+            let bits = imm.bits();
+            let signed = match dfg.ctrl_typevar(inst) {
+                types::I8 => bits as i8 as i64,
+                types::I16 => bits as i16 as i64,
+                types::I32 => bits as i32 as i64,
+                _ => bits,
+            };
+            write!(w, " {}", Imm64::new(signed))
+        }
         UnaryIeee32 { imm, .. } => write!(w, " {}", imm),
         UnaryIeee64 { imm, .. } => write!(w, " {}", imm),
         UnaryGlobalValue { global_value, .. } => write!(w, " {}", global_value),

cranelift/filetests/filetests/egraph/extends.clif

@@ -4,7 +4,7 @@ target x86_64
 
 function %f1() -> i64 {
 block0:
-  v0 = iconst.i32 0xffff_ffff_9876_5432
+  v0 = iconst.i32 0x9876_5432
   v1 = uextend.i64 v0
   return v1
   ; check: v2 = iconst.i64 0x9876_5432

cranelift/reader/src/parser.rs

@@ -12,6 +12,7 @@ use cranelift_codegen::entity::{EntityRef, PrimaryMap};
 use cranelift_codegen::ir::entities::{AnyEntity, DynamicType};
 use cranelift_codegen::ir::immediates::{Ieee32, Ieee64, Imm64, Offset32, Uimm32, Uimm64};
 use cranelift_codegen::ir::instructions::{InstructionData, InstructionFormat, VariableArgs};
+use cranelift_codegen::ir::types;
 use cranelift_codegen::ir::types::INVALID;
 use cranelift_codegen::ir::types::*;
 use cranelift_codegen::ir::{self, UserExternalNameRef};
@@ -2456,10 +2457,25 @@ impl<'a> Parser<'a> {
                 opcode,
                 arg: self.match_value("expected SSA value operand")?,
             },
-            InstructionFormat::UnaryImm => InstructionData::UnaryImm {
-                opcode,
-                imm: self.match_imm64("expected immediate integer operand")?,
-            },
+            InstructionFormat::UnaryImm => {
+                let msg = |bits| format!("expected immediate {bits}-bit integer operand");
+                let unsigned = match explicit_control_type {
+                    Some(types::I8) => self.match_imm8(&msg(8))? as u8 as i64,
+                    Some(types::I16) => self.match_imm16(&msg(16))? as u16 as i64,
+                    Some(types::I32) => self.match_imm32(&msg(32))? as u32 as i64,
+                    Some(types::I64) => self.match_imm64(&msg(64))?.bits(),
+                    _ => {
+                        return err!(
+                            self.loc,
+                            "expected one of the following type: i8, i16, i32 or i64"
+                        )
+                    }
+                };
+                InstructionData::UnaryImm {
+                    opcode,
+                    imm: Imm64::new(unsigned),
+                }
+            }
             InstructionFormat::UnaryIeee32 => InstructionData::UnaryIeee32 {
                 opcode,
                 imm: self.match_ieee32("expected immediate 32-bit float operand")?,

cranelift/tests/bugpoint_test.clif

@@ -910,7 +910,7 @@ block51:
     v428 = iadd_imm.i64 v28, 8
     v429 = load.i16 v428
         v435 -> v429
-    v430 = iconst.i16 0xffff_ffff_ffff_8000
+    v430 = iconst.i16 0x8000
     v431 = icmp eq v429, v430
     v433 = uextend.i32 v431
     brif v433, block154, block52

cranelift/wasm/src/code_translator.rs

@@ -928,7 +928,9 @@ pub fn translate_operator<FE: FuncEnvironment + ?Sized>(
             translate_store(memarg, ir::Opcode::Store, builder, state, environ)?;
         }
         /****************************** Nullary Operators ************************************/
-        Operator::I32Const { value } => state.push1(builder.ins().iconst(I32, i64::from(*value))),
+        Operator::I32Const { value } => {
+            state.push1(builder.ins().iconst(I32, *value as u32 as i64))
+        }
         Operator::I64Const { value } => state.push1(builder.ins().iconst(I64, *value)),
         Operator::F32Const { value } => {
             state.push1(builder.ins().f32const(f32_translation(*value)));

cranelift/wasm/src/environ/dummy.rs

@@ -509,7 +509,7 @@ impl<'dummy_environment> FuncEnvironment for DummyFuncEnvironment<'dummy_environ
         _heap: Heap,
         _val: ir::Value,
     ) -> WasmResult<ir::Value> {
-        Ok(pos.ins().iconst(I32, -1))
+        Ok(pos.ins().iconst(I32, -1i32 as u32 as i64))
     }
 
     fn translate_memory_size(
@@ -518,7 +518,7 @@ impl<'dummy_environment> FuncEnvironment for DummyFuncEnvironment<'dummy_environ
         _index: MemoryIndex,
         _heap: Heap,
     ) -> WasmResult<ir::Value> {
-        Ok(pos.ins().iconst(I32, -1))
+        Ok(pos.ins().iconst(I32, -1i32 as u32 as i64))
     }
 
     fn translate_memory_copy(
@@ -570,7 +570,7 @@ impl<'dummy_environment> FuncEnvironment for DummyFuncEnvironment<'dummy_environ
         _index: TableIndex,
         _table: ir::Table,
     ) -> WasmResult<ir::Value> {
-        Ok(pos.ins().iconst(I32, -1))
+        Ok(pos.ins().iconst(I32, -1i32 as u32 as i64))
     }
 
     fn translate_table_grow(
@@ -581,7 +581,7 @@ impl<'dummy_environment> FuncEnvironment for DummyFuncEnvironment<'dummy_environ
         _delta: ir::Value,
         _init_value: ir::Value,
     ) -> WasmResult<ir::Value> {
-        Ok(pos.ins().iconst(I32, -1))
+        Ok(pos.ins().iconst(I32, -1i32 as u32 as i64))
     }
 
     fn translate_table_get(
@@ -660,7 +660,7 @@ impl<'dummy_environment> FuncEnvironment for DummyFuncEnvironment<'dummy_environ
         mut pos: FuncCursor,
         _global_index: GlobalIndex,
     ) -> WasmResult<ir::Value> {
-        Ok(pos.ins().iconst(I32, -1))
+        Ok(pos.ins().iconst(I32, -1i32 as u32 as i64))
     }
 
     fn translate_custom_global_set(
@@ -681,7 +681,7 @@ impl<'dummy_environment> FuncEnvironment for DummyFuncEnvironment<'dummy_environ
         _expected: ir::Value,
         _timeout: ir::Value,
     ) -> WasmResult<ir::Value> {
-        Ok(pos.ins().iconst(I32, -1))
+        Ok(pos.ins().iconst(I32, -1i32 as u32 as i64))
     }
 
     fn translate_atomic_notify(