[llvm-branch-commits] [llvm] bde97f2 - [Mips] Fix wrong ELF FP ABI info when inline asm was empty (#146457)

[Tobias Hieta via llvm-branch-commits]

Author: yingopq
Date: 2025-07-29T09:44:28+02:00
New Revision: bde97f2cefba49a9753c23517918c07e743a9a9b

URL: https://github.com/llvm/llvm-project/commit/bde97f2cefba49a9753c23517918c07e743a9a9b
DIFF: https://github.com/llvm/llvm-project/commit/bde97f2cefba49a9753c23517918c07e743a9a9b.diff

LOG: [Mips] Fix wrong ELF FP ABI info when inline asm was empty (#146457)

When Mips process emitStartOfAsmFile and updateABIInfo, it did not know
the real value of IsSoftFloat and STI.useSoftFloat(). And when inline
asm instruction was empty, Mips did not process asm parser, so it would
not do TS.updateABIInfo(STI) again and at this time the value of
IsSoftFloat is correct.

Fix #135283.

(cherry picked from commit 778fb76e6308534a63239a91b98f5dad055f6fdb)

Added: 
    llvm/test/CodeGen/Mips/abiflags-soft-float.ll

Modified: 
    llvm/lib/Target/Mips/MipsAsmPrinter.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/Mips/MipsAsmPrinter.cpp b/llvm/lib/Target/Mips/MipsAsmPrinter.cpp
index 87e06a6d3c08a..2903ff75475cf 100644
--- a/llvm/lib/Target/Mips/MipsAsmPrinter.cpp
+++ b/llvm/lib/Target/Mips/MipsAsmPrinter.cpp
@@ -747,14 +747,18 @@ void MipsAsmPrinter::emitStartOfAsmFile(Module &M) {
     if (FS.empty() && M.size() && F->hasFnAttribute("target-features"))
       FS = F->getFnAttribute("target-features").getValueAsString();
 
+    std::string strFS = FS.str();
+    if (M.size() && F->getFnAttribute("use-soft-float").getValueAsBool())
+      strFS += strFS.empty() ? "+soft-float" : ",+soft-float";
+
     // Compute MIPS architecture attributes based on the default subtarget
     // that we'd have constructed.
     // FIXME: For ifunc related functions we could iterate over and look
     // for a feature string that doesn't match the default one.
     StringRef CPU = MIPS_MC::selectMipsCPU(TT, TM.getTargetCPU());
     const MipsTargetMachine &MTM = static_cast<const MipsTargetMachine &>(TM);
-    const MipsSubtarget STI(TT, CPU, FS, MTM.isLittleEndian(), MTM,
-                            std::nullopt);
+    const MipsSubtarget STI(TT, CPU, StringRef(strFS), MTM.isLittleEndian(),
+                            MTM, std::nullopt);
 
     bool IsABICalls = STI.isABICalls();
     const MipsABIInfo &ABI = MTM.getABI();

diff  --git a/llvm/test/CodeGen/Mips/abiflags-soft-float.ll b/llvm/test/CodeGen/Mips/abiflags-soft-float.ll
new file mode 100644
index 0000000000000..01821f2d9b6c6
--- /dev/null
+++ b/llvm/test/CodeGen/Mips/abiflags-soft-float.ll
@@ -0,0 +1,12 @@
+; RUN: llc -filetype=obj -mtriple mipsel-unknown-linux -mcpu=mips32 %s -o tmp.o
+; RUN: llvm-readobj -A tmp.o | FileCheck %s -check-prefix=OBJ
+; RUN: llc -filetype=asm -mtriple mipsel-unknown-linux -mcpu=mips32 %s -o - | \
+; RUN: FileCheck %s -check-prefix=ASM
+
+; OBJ: FP ABI: Soft float
+; ASM: .module	softfloat 
+
+define dso_local void @asm_is_null() "use-soft-float"="true" {
+  call void asm sideeffect "", ""()
+  ret void
+}