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Ensure vectors are bitcast to the correct type

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Due to SIMD's v128 operations, vectors that may have had an explicit type (e.g. f32x4) before a v128 operation will subsequently have CLIF's v128 stand-in type: i8x16. In order for follow-on operations (that may be more stricly typed, e.g. f32x4.add) to avoid CLIF errors, we must bitcast them back to the operation type. The raw_bitcast operation used to do this emits no machine code but does incur some small compile-time cost; it would be nice to avoid this in the future.
This commit is contained in:
Andrew Brown
2019-10-29 09:59:35 -07:00
parent b425ddc52d
commit a2b28f9472
1 changed files with 12 additions and 14 deletions
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26
cranelift/wasm/src/code_translator.rs
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@@ -1019,12 +1019,12 @@ pub fn translate_operator<FE: FuncEnvironment + ?Sized>(
state.push1(splatted)
}
Operator::I8x16ExtractLaneS { lane } | Operator::I16x8ExtractLaneS { lane } => {
let vector = optionally_bitcast_vector(state.pop1(), type_of(op), builder);
let vector = pop1_with_bitcast(state, type_of(op), builder);
let extracted = builder.ins().extractlane(vector, lane.clone());
state.push1(builder.ins().sextend(I32, extracted))
}
Operator::I8x16ExtractLaneU { lane } | Operator::I16x8ExtractLaneU { lane } => {
let vector = optionally_bitcast_vector(state.pop1(), type_of(op), builder);
let vector = pop1_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().extractlane(vector, lane.clone()));
// on x86, PEXTRB zeroes the upper bits of the destination register of extractlane so uextend is elided; of course, this depends on extractlane being legalized to a PEXTRB
}
@@ -1032,7 +1032,7 @@ pub fn translate_operator<FE: FuncEnvironment + ?Sized>(
| Operator::I64x2ExtractLane { lane }
| Operator::F32x4ExtractLane { lane }
| Operator::F64x2ExtractLane { lane } => {
let vector = optionally_bitcast_vector(state.pop1(), type_of(op), builder);
let vector = pop1_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().extractlane(vector, lane.clone()))
}
Operator::I8x16ReplaceLane { lane }
@@ -1054,9 +1054,7 @@ pub fn translate_operator<FE: FuncEnvironment + ?Sized>(
))
}
Operator::V8x16Shuffle { lanes, .. } => {
let (vector_a, vector_b) = state.pop2();
let a = optionally_bitcast_vector(vector_a, I8X16, builder);
let b = optionally_bitcast_vector(vector_b, I8X16, builder);
let (a, b) = pop2_with_bitcast(state, I8X16, builder);
let lanes = ConstantData::from(lanes.as_ref());
let mask = builder.func.dfg.immediates.push(lanes);
let shuffled = builder.ins().shuffle(a, b, mask);
@@ -1067,35 +1065,35 @@ pub fn translate_operator<FE: FuncEnvironment + ?Sized>(
// types (e.g. i8x16) for others.
}
Operator::I8x16Add | Operator::I16x8Add | Operator::I32x4Add | Operator::I64x2Add => {
let (a, b) = state.pop2();
let (a, b) = pop2_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().iadd(a, b))
}
Operator::I8x16AddSaturateS | Operator::I16x8AddSaturateS => {
let (a, b) = state.pop2();
let (a, b) = pop2_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().sadd_sat(a, b))
}
Operator::I8x16AddSaturateU | Operator::I16x8AddSaturateU => {
let (a, b) = state.pop2();
let (a, b) = pop2_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().uadd_sat(a, b))
}
Operator::I8x16Sub | Operator::I16x8Sub | Operator::I32x4Sub | Operator::I64x2Sub => {
let (a, b) = state.pop2();
let (a, b) = pop2_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().isub(a, b))
}
Operator::I8x16SubSaturateS | Operator::I16x8SubSaturateS => {
let (a, b) = state.pop2();
let (a, b) = pop2_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().ssub_sat(a, b))
}
Operator::I8x16SubSaturateU | Operator::I16x8SubSaturateU => {
let (a, b) = state.pop2();
let (a, b) = pop2_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().usub_sat(a, b))
}
Operator::I8x16Neg | Operator::I16x8Neg | Operator::I32x4Neg | Operator::I64x2Neg => {
let a = state.pop1();
let a = pop1_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().ineg(a))
}
Operator::I16x8Mul | Operator::I32x4Mul => {
let (a, b) = state.pop2();
let (a, b) = pop2_with_bitcast(state, type_of(op), builder);
state.push1(builder.ins().imul(a, b))
}
Operator::V128Not => {