[llvm][LoongArch] Improve the "out of range" error information reported by `adjustFixupValue`

[XiaodongLoong]

Summary

There are three reduplicate error messages for different conditions. I
add meaningful information to make them more informative.

[SixWeining]

llvm/test/MC/LoongArch/Relocations/fixups-diagnostics.s

1

Seems you are using an old code base.

[XiaodongLoong]

rebase code

[SixWeining]

llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp

98

Should be "bits" or something else?

[XiaodongLoong]

llvm/test/MC/LoongArch/Relocations/fixups-diagnostics.s

1

Yes, I rebased code.

[MaskRay]

llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp

98

You can define a method to return a string fixup value out of range [-xxx, xxx]

[MaskRay]

, NFC

There is a functional change, so not NFC.

[XiaodongLoong]

Update patch for review comments.

[XiaodongLoong]

I defined a method named "reportOutOfRangeError" to report "out of range" error. Thanks!

[MaskRay]

LGTM.

llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp

82

Remove the two variables. Use llvm::minIntN(N) and llvm::maxIntN(N) in `Twine.

85

Remove .str()

[XiaodongLoong]

Use llvm::minIntN(N) and llvm::maxIntN(N) and remove .str()

[XiaodongLoong]

Use llvm::minIntN(N) and llvm::maxIntN(N) and remove .str(). Done.

[MaskRay]

llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp

82

The function just uses the Location, so a SMLoc parameter is more appropriate.
MCContext is usually added as the first parameter.

[XiaodongLoong]

Change parameters type and order

llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp

LoongArchAsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
   if (Kind < FirstTargetFixupKind)
     return MCAsmBackend::getFixupKindInfo(Kind);
 
   assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() &&
          "Invalid kind!");
   return Infos[Kind - FirstTargetFixupKind];
 }
 
+static void reportOutOfRangeError(MCContext &Ctx, SMLoc Loc, unsigned N) {
+  Ctx.reportError(Loc, "fixup value out of range [" + Twine(llvm::minIntN(N)) +
+                           ", " + Twine(llvm::maxIntN(N)) + "]");
+}
+
 static uint64_t adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
                                  MCContext &Ctx) {
   switch (Fixup.getTargetKind()) {
   default:
     llvm_unreachable("Unknown fixup kind");
   case FK_Data_1:
   case FK_Data_2:
   case FK_Data_4:
   case FK_Data_8:
     return Value;
   case LoongArch::fixup_loongarch_b16: {
     if (!isInt<18>(Value))
-      Ctx.reportError(Fixup.getLoc(), "fixup value out of range");
+      reportOutOfRangeError(Ctx, Fixup.getLoc(), 18);
     if (Value % 4)
       Ctx.reportError(Fixup.getLoc(), "fixup value must be 4-byte aligned");
     return (Value >> 2) & 0xffff;
   }
   case LoongArch::fixup_loongarch_b21: {
     if (!isInt<23>(Value))
-      Ctx.reportError(Fixup.getLoc(), "fixup value out of range");
+      reportOutOfRangeError(Ctx, Fixup.getLoc(), 23);
     if (Value % 4)
       Ctx.reportError(Fixup.getLoc(), "fixup value must be 4-byte aligned");
     return ((Value & 0x3fffc) << 8) | ((Value >> 18) & 0x1f);
   }
   case LoongArch::fixup_loongarch_b26: {
     if (!isInt<28>(Value))
-      Ctx.reportError(Fixup.getLoc(), "fixup value out of range");
+      reportOutOfRangeError(Ctx, Fixup.getLoc(), 28);
     if (Value % 4)
       Ctx.reportError(Fixup.getLoc(), "fixup value must be 4-byte aligned");
     return ((Value & 0x3fffc) << 8) | ((Value >> 18) & 0x3ff);
   }
   case LoongArch::fixup_loongarch_abs_hi20:
   case LoongArch::fixup_loongarch_tls_le_hi20:
     return (Value >> 12) & 0xfffff;
   case LoongArch::fixup_loongarch_abs_lo12:

llvm/test/MC/LoongArch/Relocations/fixups-diagnostics.s

 # RUN: not llvm-mc --triple=loongarch64 --filetype=obj %s -o /dev/null 2>&1 | FileCheck %s
 
   beq $a0, $a1, unaligned # CHECK: :[[#@LINE]]:3: error: fixup value must be 4-byte aligned
   beqz $a0, unaligned # CHECK: :[[#@LINE]]:3: error: fixup value must be 4-byte aligned
   b unaligned # CHECK: :[[#@LINE]]:3: error: fixup value must be 4-byte aligned
   .byte 0
 unaligned:
   .byte 0
   .byte 0
   .byte 0
 
-  beq $a0, $a1, out_of_range_b16 # CHECK: :[[#@LINE]]:3: error: fixup value out of range
+  beq $a0, $a1, out_of_range_b18 # CHECK: :[[#@LINE]]:3: error: fixup value out of range [-131072, 131071]
   .space 1<<18
-out_of_range_b16:
-  beqz $a0, out_of_range_b21 # CHECK: :[[#@LINE]]:3: error: fixup value out of range
+out_of_range_b18:
+  beqz $a0, out_of_range_b23 # CHECK: :[[#@LINE]]:3: error: fixup value out of range [-4194304, 4194303]
   .space 1<<23
-out_of_range_b21:
-  b out_of_range_b26 # CHECK: :[[#@LINE]]:3: error: fixup value out of range
+out_of_range_b23:
+  b out_of_range_b28 # CHECK: :[[#@LINE]]:3: error: fixup value out of range [-134217728, 134217727]
   .space 1<<28
-out_of_range_b26:
+out_of_range_b28: