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Return 0 from cpuid for all subleaves of leaf 7

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This is necessary to support the cpufeatures crate

Fixes #1173
This commit is contained in:
bjorn3 2021-05-16 10:46:34 +02:00
parent 328f06718a
commit a9d033d0e5
1 changed files with 7 additions and 0 deletions
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7
src/intrinsics/cpuid.rs
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@ -12,6 +12,7 @@ pub(crate) fn codegen_cpuid_call<'tcx>(
) -> (Value, Value, Value, Value) {
let leaf_0 = fx.bcx.create_block();
let leaf_1 = fx.bcx.create_block();
let leaf_7 = fx.bcx.create_block();
let leaf_8000_0000 = fx.bcx.create_block();
let leaf_8000_0001 = fx.bcx.create_block();
let unsupported_leaf = fx.bcx.create_block();
@ -25,6 +26,7 @@ pub(crate) fn codegen_cpuid_call<'tcx>(
let mut switch = cranelift_frontend::Switch::new();
switch.set_entry(0, leaf_0);
switch.set_entry(1, leaf_1);
switch.set_entry(7, leaf_7);
switch.set_entry(0x8000_0000, leaf_8000_0000);
switch.set_entry(0x8000_0001, leaf_8000_0001);
switch.emit(&mut fx.bcx, leaf, unsupported_leaf);
@ -43,6 +45,11 @@ pub(crate) fn codegen_cpuid_call<'tcx>(
let edx_features = fx.bcx.ins().iconst(types::I32, 1 << 25 /* sse */ | 1 << 26 /* sse2 */);
fx.bcx.ins().jump(dest, &[cpu_signature, additional_information, ecx_features, edx_features]);
fx.bcx.switch_to_block(leaf_7);
// This leaf technically has subleaves, but we just return zero for all subleaves.
let zero = fx.bcx.ins().iconst(types::I32, 0);
fx.bcx.ins().jump(dest, &[zero, zero, zero, zero]);
fx.bcx.switch_to_block(leaf_8000_0000);
let extended_max_basic_leaf = fx.bcx.ins().iconst(types::I32, 0);
let zero = fx.bcx.ins().iconst(types::I32, 0);