[lld] Check for branch range overflows.

[sidneym]

Summary

Check for branch range overflows and add a testcase.

[bcain]

LGTM, but suggestions for stricter test case.

lld/test/ELF/hexagon-verify.s

5–9 ↗

(On Diff #224614)

I'd make the subsequent ones CHECK-NEXT.

Also may make sense to constrain the FileCheck with implicit-check-not='out of range' to make sure no range errors are emitted that aren't checked for.

[sidneym]

Update test case.

[MaskRay]

lld/test/ELF/hexagon-verify.s

5 ↗

(On Diff #224637)

#CHECK -> # CHECK

If such branch relocation types have a categorical name, e.g. jump, consider rename this test to something like hexagon-jump-error.s

x86-64-reloc-error.s
aarch64-lo21-error.s  # the name is good

[MaskRay]

lld/test/ELF/hexagon-verify.s

21 ↗

(On Diff #224637)

Consider moving the CHECK lines just before the corresponding instructions.

28 ↗

(On Diff #224637)

If jump #b15 works, you can delete the local label pc15.

[sidneym]

Update and rename testcase.

[ruiu]

LGTM

lld/ELF/Arch/Hexagon.cpp

case R_HEX_32_PCREL:
     or32le(loc, val);
     break;
   case R_HEX_32_6_X:
   case R_HEX_GOT_32_6_X:
   case R_HEX_GOTREL_32_6_X:
     or32le(loc, applyMask(0x0fff3fff, val >> 6));
     break;
   case R_HEX_B9_PCREL:
+    checkInt(loc, val, 11, type);
     or32le(loc, applyMask(0x003000fe, val >> 2));
     break;
   case R_HEX_B9_PCREL_X:
     or32le(loc, applyMask(0x003000fe, val & 0x3f));
     break;
   case R_HEX_B13_PCREL:
+    checkInt(loc, val, 15, type);
     or32le(loc, applyMask(0x00202ffe, val >> 2));
     break;
   case R_HEX_B15_PCREL:
+    checkInt(loc, val, 17, type);
     or32le(loc, applyMask(0x00df20fe, val >> 2));
     break;
   case R_HEX_B15_PCREL_X:
     or32le(loc, applyMask(0x00df20fe, val & 0x3f));
     break;
   case R_HEX_B22_PCREL:
   case R_HEX_PLT_B22_PCREL:
+    checkInt(loc, val, 22, type);
     or32le(loc, applyMask(0x1ff3ffe, val >> 2));
     break;
   case R_HEX_B22_PCREL_X:
     or32le(loc, applyMask(0x1ff3ffe, val & 0x3f));
     break;
   case R_HEX_B32_PCREL_X:
     or32le(loc, applyMask(0x0fff3fff, val >> 6));
     break;

lld/test/ELF/hexagon-jump-error.s

+# REQUIRES: hexagon
+# RUN: llvm-mc -filetype=obj -triple=hexagon-unknown-elf %s -o %t.o
+# RUN: not ld.lld %t.o -o %t 2>&1 | FileCheck --implicit-check-not "out of range" %s
+
+  .globl  _start
+  .type _start, @function
+_start:
+
+# CHECK: relocation R_HEX_B9_PCREL out of range: 1028 is not in [-1024, 1023]
+{r0 = #0; jump #1f}
+.space (1<<10)
+.section b9, "ax"
+1:
+
+# CHECK-NEXT: relocation R_HEX_B13_PCREL out of range: 16388 is not in [-16384, 16383]
+if (r0==#0) jump:t #1f
+.space (1<<14)
+.section b13, "ax"
+1:
+
+# CHECK-NEXT: relocation R_HEX_B15_PCREL out of range: 65540 is not in [-65536, 65535]
+if (p0) jump #1f
+.space (1<<16)
+.section b15, "ax"
+1:
+
+# CHECK-NEXT: relocation R_HEX_B22_PCREL out of range: 8388612 is not in [-2097152, 2097151]
+jump #1f
+.space (1<<23)
+.section b22, "ax"
+1: