llvm: Update the list of targets that use native f16/f128.

Closes #22003.
Closes #22013.

Author: alexrp

lib/compiler_rt/common.zig

@@ -96,21 +96,25 @@ pub const want_sparc_abi = builtin.cpu.arch.isSPARC();
 // we're trying to test compiler-rt.
 pub const panic = if (builtin.is_test) std.debug.FullPanic(std.debug.defaultPanic) else std.debug.no_panic;
 
-/// AArch64 is the only ABI (at the moment) to support f16 arguments without the
-/// need for extending them to wider fp types.
-/// TODO remove this; do this type selection in the language rather than
-/// here in compiler-rt.
+/// This seems to mostly correspond to `clang::TargetInfo::HasFloat16`.
 pub fn F16T(comptime OtherType: type) type {
     return switch (builtin.cpu.arch) {
-        .arm, .armeb, .thumb, .thumbeb => if (std.Target.arm.featureSetHas(builtin.cpu.features, .has_v8))
-            switch (builtin.abi.float()) {
-                .soft => u16,
-                .hard => f16,
-            }
-        else
-            u16,
-        .aarch64, .aarch64_be => f16,
-        .riscv32, .riscv64 => f16,
+        .amdgcn,
+        .arm,
+        .armeb,
+        .thumb,
+        .thumbeb,
+        .aarch64,
+        .aarch64_be,
+        .nvptx,
+        .nvptx64,
+        .riscv32,
+        .riscv64,
+        .spirv,
+        .spirv32,
+        .spirv64,
+        => f16,
+        .hexagon => if (std.Target.hexagon.featureSetHas(builtin.target.cpu.features, .v68)) f16 else u16,
         .x86, .x86_64 => if (builtin.target.os.tag.isDarwin()) switch (OtherType) {
             // Starting with LLVM 16, Darwin uses different abi for f16
             // depending on the type of the other return/argument..???

src/codegen/llvm.zig

@@ -12472,29 +12472,30 @@ fn backendSupportsF80(target: std.Target) bool {
 /// or if it produces miscompilations.
 fn backendSupportsF16(target: std.Target) bool {
     return switch (target.cpu.arch) {
-        // LoongArch can be removed from this list with LLVM 20.
-        .loongarch32,
-        .loongarch64,
+        // https://github.com/llvm/llvm-project/issues/97981
+        .csky,
+        // https://github.com/llvm/llvm-project/issues/97981
         .hexagon,
+        // https://github.com/llvm/llvm-project/issues/97981
         .powerpc,
         .powerpcle,
         .powerpc64,
         .powerpc64le,
+        // https://github.com/llvm/llvm-project/issues/97981
         .wasm32,
         .wasm64,
-        .mips,
-        .mipsel,
-        .mips64,
-        .mips64el,
+        // https://github.com/llvm/llvm-project/issues/50374
         .s390x,
+        // https://github.com/llvm/llvm-project/issues/97981
         .sparc,
         .sparc64,
         => false,
         .arm,
         .armeb,
         .thumb,
         .thumbeb,
-        => target.abi.float() == .soft or std.Target.arm.featureSetHas(target.cpu.features, .fp_armv8),
+        => target.abi.float() == .soft or std.Target.arm.featureSetHas(target.cpu.features, .fullfp16),
+        // https://github.com/llvm/llvm-project/issues/129394
         .aarch64,
         .aarch64_be,
         => std.Target.aarch64.featureSetHas(target.cpu.features, .fp_armv8),
@@ -12507,11 +12508,18 @@ fn backendSupportsF16(target: std.Target) bool {
 /// or if it produces miscompilations.
 fn backendSupportsF128(target: std.Target) bool {
     return switch (target.cpu.arch) {
+        // https://github.com/llvm/llvm-project/issues/121122
         .amdgcn,
+        // Test failures all over the place.
         .mips64,
         .mips64el,
+        // https://github.com/llvm/llvm-project/issues/95471
+        .nvptx,
+        .nvptx64,
+        // https://github.com/llvm/llvm-project/issues/41838
         .sparc,
         => false,
+        // https://github.com/llvm/llvm-project/issues/101545
         .powerpc,
         .powerpcle,
         .powerpc64,
@@ -12522,9 +12530,6 @@ fn backendSupportsF128(target: std.Target) bool {
         .thumb,
         .thumbeb,
         => target.abi.float() == .soft or std.Target.arm.featureSetHas(target.cpu.features, .fp_armv8),
-        .aarch64,
-        .aarch64_be,
-        => std.Target.aarch64.featureSetHas(target.cpu.features, .fp_armv8),
         else => true,
     };
 }