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Merge commit 'f2cdd4a78d89c009342197cf5844a21f8aa813df' into sync_cg_clif-2022-04-22

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bjorn3
2022-04-22 21:11:38 +02:00
parent 41ef767806 f2cdd4a78d
commit b70b01b112
21 changed files with 189 additions and 142 deletions
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24
compiler/rustc_codegen_cranelift/src/intrinsics/mod.rs
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@@ -1019,39 +1019,23 @@ fn codegen_regular_intrinsic_call<'tcx>(
ret.write_cvalue(fx, old);
};
// In Rust floating point min and max don't propagate NaN. In Cranelift they do however.
// For this reason it is necessary to use `a.is_nan() ? b : (a >= b ? b : a)` for `minnumf*`
// and `a.is_nan() ? b : (a <= b ? b : a)` for `maxnumf*`. NaN checks are done by comparing
// a float against itself. Only in case of NaN is it not equal to itself.
minnumf32, (v a, v b) {
let a_is_nan = fx.bcx.ins().fcmp(FloatCC::NotEqual, a, a);
let a_ge_b = fx.bcx.ins().fcmp(FloatCC::GreaterThanOrEqual, a, b);
let temp = fx.bcx.ins().select(a_ge_b, b, a);
let val = fx.bcx.ins().select(a_is_nan, b, temp);
let val = crate::num::codegen_float_min(fx, a, b);
let val = CValue::by_val(val, fx.layout_of(fx.tcx.types.f32));
ret.write_cvalue(fx, val);
};
minnumf64, (v a, v b) {
let a_is_nan = fx.bcx.ins().fcmp(FloatCC::NotEqual, a, a);
let a_ge_b = fx.bcx.ins().fcmp(FloatCC::GreaterThanOrEqual, a, b);
let temp = fx.bcx.ins().select(a_ge_b, b, a);
let val = fx.bcx.ins().select(a_is_nan, b, temp);
let val = crate::num::codegen_float_min(fx, a, b);
let val = CValue::by_val(val, fx.layout_of(fx.tcx.types.f64));
ret.write_cvalue(fx, val);
};
maxnumf32, (v a, v b) {
let a_is_nan = fx.bcx.ins().fcmp(FloatCC::NotEqual, a, a);
let a_le_b = fx.bcx.ins().fcmp(FloatCC::LessThanOrEqual, a, b);
let temp = fx.bcx.ins().select(a_le_b, b, a);
let val = fx.bcx.ins().select(a_is_nan, b, temp);
let val = crate::num::codegen_float_max(fx, a, b);
let val = CValue::by_val(val, fx.layout_of(fx.tcx.types.f32));
ret.write_cvalue(fx, val);
};
maxnumf64, (v a, v b) {
let a_is_nan = fx.bcx.ins().fcmp(FloatCC::NotEqual, a, a);
let a_le_b = fx.bcx.ins().fcmp(FloatCC::LessThanOrEqual, a, b);
let temp = fx.bcx.ins().select(a_le_b, b, a);
let val = fx.bcx.ins().select(a_is_nan, b, temp);
let val = crate::num::codegen_float_max(fx, a, b);
let val = CValue::by_val(val, fx.layout_of(fx.tcx.types.f64));
ret.write_cvalue(fx, val);
};