rustc_llvm: expose FloatABIType target machine parameter

Author: RalfJung

compiler/rustc_codegen_llvm/src/back/owned_target_machine.rs

@@ -25,7 +25,7 @@ impl OwnedTargetMachine {
         model: llvm::CodeModel,
         reloc: llvm::RelocModel,
         level: llvm::CodeGenOptLevel,
-        use_soft_fp: bool,
+        float_abi: llvm::FloatAbi,
         function_sections: bool,
         data_sections: bool,
         unique_section_names: bool,
@@ -57,7 +57,7 @@ impl OwnedTargetMachine {
                 model,
                 reloc,
                 level,
-                use_soft_fp,
+                float_abi,
                 function_sections,
                 data_sections,
                 unique_section_names,

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -40,7 +40,7 @@ use crate::errors::{
     WithLlvmError, WriteBytecode,
 };
 use crate::llvm::diagnostic::OptimizationDiagnosticKind::*;
-use crate::llvm::{self, DiagnosticInfo, PassManager};
+use crate::llvm::{self, DiagnosticInfo, FloatAbi, PassManager};
 use crate::type_::Type;
 use crate::{LlvmCodegenBackend, ModuleLlvm, base, common, llvm_util};
 
@@ -189,12 +189,12 @@ pub(crate) fn target_machine_factory(
     let reloc_model = to_llvm_relocation_model(sess.relocation_model());
 
     let (opt_level, _) = to_llvm_opt_settings(optlvl);
-    let use_softfp = if sess.target.arch == "arm" {
-        sess.opts.cg.soft_float
+    let float_abi = if sess.target.arch == "arm" && sess.opts.cg.soft_float {
+        FloatAbi::Soft
     } else {
         // `validate_commandline_args_with_session_available` has already warned about this being
         // ignored. Let's make sure LLVM doesn't suddenly start using this flag on more targets.
-        false
+        FloatAbi::Default
     };
 
     let ffunction_sections =
@@ -290,7 +290,7 @@ pub(crate) fn target_machine_factory(
             code_model,
             reloc_model,
             opt_level,
-            use_softfp,
+            float_abi,
             ffunction_sections,
             fdata_sections,
             funique_section_names,

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -526,7 +526,7 @@ pub struct SanitizerOptions {
     pub sanitize_kernel_address_recover: bool,
 }
 
-/// LLVMRelocMode
+/// LLVMRustRelocModel
 #[derive(Copy, Clone, PartialEq)]
 #[repr(C)]
 pub enum RelocModel {
@@ -538,6 +538,15 @@ pub enum RelocModel {
     ROPI_RWPI,
 }
 
+/// LLVMRustFloatABI
+#[derive(Copy, Clone, PartialEq)]
+#[repr(C)]
+pub enum FloatAbi {
+    Default,
+    Soft,
+    Hard,
+}
+
 /// LLVMRustCodeModel
 #[derive(Copy, Clone)]
 #[repr(C)]
@@ -2192,7 +2201,7 @@ unsafe extern "C" {
         Model: CodeModel,
         Reloc: RelocModel,
         Level: CodeGenOptLevel,
-        UseSoftFP: bool,
+        FloatABIType: FloatAbi,
         FunctionSections: bool,
         DataSections: bool,
         UniqueSectionNames: bool,

compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp

@@ -308,6 +308,24 @@ static Reloc::Model fromRust(LLVMRustRelocModel RustReloc) {
   report_fatal_error("Bad RelocModel.");
 }
 
+enum class LLVMRustFloatABI {
+  Default,
+  Soft,
+  Hard,
+};
+
+static FloatABI::ABIType fromRust(LLVMRustFloatABI RustFloatAbi) {
+  switch (RustFloatAbi) {
+  case LLVMRustFloatABI::Default:
+    return FloatABI::Default;
+  case LLVMRustFloatABI::Soft:
+    return FloatABI::Soft;
+  case LLVMRustFloatABI::Hard:
+    return FloatABI::Hard;
+  }
+  report_fatal_error("Bad FloatABI.");
+}
+
 /// getLongestEntryLength - Return the length of the longest entry in the table.
 template <typename KV> static size_t getLongestEntryLength(ArrayRef<KV> Table) {
   size_t MaxLen = 0;
@@ -358,7 +376,7 @@ extern "C" const char *LLVMRustGetHostCPUName(size_t *OutLen) {
 extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
     const char *TripleStr, const char *CPU, const char *Feature,
     const char *ABIStr, LLVMRustCodeModel RustCM, LLVMRustRelocModel RustReloc,
-    LLVMRustCodeGenOptLevel RustOptLevel, bool UseSoftFloat,
+    LLVMRustCodeGenOptLevel RustOptLevel, LLVMRustFloatABI RustFloatABIType,
     bool FunctionSections, bool DataSections, bool UniqueSectionNames,
     bool TrapUnreachable, bool Singlethread, bool VerboseAsm,
     bool EmitStackSizeSection, bool RelaxELFRelocations, bool UseInitArray,
@@ -369,6 +387,7 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
   auto OptLevel = fromRust(RustOptLevel);
   auto RM = fromRust(RustReloc);
   auto CM = fromRust(RustCM);
+  auto FloatABIType = fromRust(RustFloatABIType);
 
   std::string Error;
   auto Trip = Triple(Triple::normalize(TripleStr));
@@ -381,10 +400,7 @@ extern "C" LLVMTargetMachineRef LLVMRustCreateTargetMachine(
 
   TargetOptions Options = codegen::InitTargetOptionsFromCodeGenFlags(Trip);
 
-  Options.FloatABIType = FloatABI::Default;
-  if (UseSoftFloat) {
-    Options.FloatABIType = FloatABI::Soft;
-  }
+  Options.FloatABIType = FloatABIType;
   Options.DataSections = DataSections;
   Options.FunctionSections = FunctionSections;
   Options.UniqueSectionNames = UniqueSectionNames;