[RISCV] Add R_RISCV_RELAX relocation to all possible relax candidates.

Summary:
Add R_RISCV_RELAX relocation to all possible relax candidates and
update corresponding testcase.

Reviewers: asb, apazos

Differential Revision: https://reviews.llvm.org/D46677

llvm-svn: 351723

lib/Target/RISCV/MCTargetDesc/RISCVMCCodeEmitter.cpp

@@ -204,6 +204,7 @@ unsigned RISCVMCCodeEmitter::getImmOpValue(const MCInst &MI, unsigned OpNo,
   const MCExpr *Expr = MO.getExpr();
   MCExpr::ExprKind Kind = Expr->getKind();
   RISCV::Fixups FixupKind = RISCV::fixup_riscv_invalid;
+  bool RelaxCandidate = false;
   if (Kind == MCExpr::Target) {
     const RISCVMCExpr *RVExpr = cast<RISCVMCExpr>(Expr);
 
@@ -218,9 +219,11 @@ unsigned RISCVMCCodeEmitter::getImmOpValue(const MCInst &MI, unsigned OpNo,
         FixupKind = RISCV::fixup_riscv_lo12_s;
       else
         llvm_unreachable("VK_RISCV_LO used with unexpected instruction format");
+      RelaxCandidate = true;
       break;
     case RISCVMCExpr::VK_RISCV_HI:
       FixupKind = RISCV::fixup_riscv_hi20;
+      RelaxCandidate = true;
       break;
     case RISCVMCExpr::VK_RISCV_PCREL_LO:
       if (MIFrm == RISCVII::InstFormatI)
@@ -230,12 +233,15 @@ unsigned RISCVMCCodeEmitter::getImmOpValue(const MCInst &MI, unsigned OpNo,
       else
         llvm_unreachable(
             "VK_RISCV_PCREL_LO used with unexpected instruction format");
+      RelaxCandidate = true;
       break;
     case RISCVMCExpr::VK_RISCV_PCREL_HI:
       FixupKind = RISCV::fixup_riscv_pcrel_hi20;
+      RelaxCandidate = true;
       break;
     case RISCVMCExpr::VK_RISCV_CALL:
       FixupKind = RISCV::fixup_riscv_call;
+      RelaxCandidate = true;
       break;
     }
   } else if (Kind == MCExpr::SymbolRef &&
@@ -257,13 +263,15 @@ unsigned RISCVMCCodeEmitter::getImmOpValue(const MCInst &MI, unsigned OpNo,
       MCFixup::create(0, Expr, MCFixupKind(FixupKind), MI.getLoc()));
   ++MCNumFixups;
 
-  if (EnableRelax) {
+  // Ensure an R_RISCV_RELAX relocation will be emitted if linker relaxation is
-    if (FixupKind == RISCV::fixup_riscv_call) {
+  // enabled and the current fixup will result in a relocation that may be
-      Fixups.push_back(
+  // relaxed.
-      MCFixup::create(0, Expr, MCFixupKind(RISCV::fixup_riscv_relax),
+  if (EnableRelax && RelaxCandidate) {
-                      MI.getLoc()));
+    const MCConstantExpr *Dummy = MCConstantExpr::create(0, Ctx);
-      ++MCNumFixups;
+    Fixups.push_back(
-    }
+    MCFixup::create(0, Dummy, MCFixupKind(RISCV::fixup_riscv_relax),
+                    MI.getLoc()));
+    ++MCNumFixups;
   }
 
   return 0;

test/MC/RISCV/linker-relaxation.s

@@ -18,9 +18,58 @@ call foo
 # NORELAX-RELOC: R_RISCV_CALL foo 0x0
 # NORELAX-RELOC-NOT: R_RISCV_RELAX
 # RELAX-RELOC: R_RISCV_CALL foo 0x0
-# RELAX-RELOC: R_RISCV_RELAX foo 0x0
+# RELAX-RELOC: R_RISCV_RELAX - 0x0
 # RELAX-FIXUP: fixup A - offset: 0, value: foo, kind: fixup_riscv_call
-# RELAX-FIXUP: fixup B - offset: 0, value: foo, kind: fixup_riscv_relax
+# RELAX-FIXUP: fixup B - offset: 0, value: 0, kind: fixup_riscv_relax
 beq s1, s1, .L1
 # RELAX-RELOC: R_RISCV_BRANCH .L1 0x0
 # RELAX-FIXUP: fixup A - offset: 0, value: .L1, kind: fixup_riscv_branch
+# RELAX-FIXUP-NOT: fixup B - offset: 0, value: 0, kind: fixup_riscv_relax
+
+lui t1, %hi(foo)
+# NORELAX-RELOC: R_RISCV_HI20 foo 0x0
+# NORELAX-RELOC-NOT: R_RISCV_RELAX
+# RELOC: R_RISCV_HI20 foo 0x0
+# RELAX-RELOC: R_RISCV_RELAX - 0x0
+# RELAX-FIXUP: fixup A - offset: 0, value: %hi(foo), kind: fixup_riscv_hi20
+# RELAX-FIXUP: fixup B - offset: 0, value: 0, kind: fixup_riscv_relax
+
+addi t1, t1, %lo(foo)
+# NORELAX-RELOC: R_RISCV_LO12_I foo 0x0
+# NORELAX-RELOC-NOT: R_RISCV_RELAX
+# RELOC: R_RISCV_LO12_I foo 0x0
+# RELAX-RELOC: R_RISCV_RELAX - 0x0
+# RELAX-FIXUP: fixup A - offset: 0, value: %lo(foo), kind: fixup_riscv_lo12_i
+# RELAX-FIXUP: fixup B - offset: 0, value: 0, kind: fixup_riscv_relax
+
+sb t1, %lo(foo)(a2)
+# NORELAX-RELOC: R_RISCV_LO12_S foo 0x0
+# NORELAX-RELOC-NOT: R_RISCV_RELAX
+# RELOC: R_RISCV_LO12_S foo 0x0
+# RELAX-RELOC: R_RISCV_RELAX - 0x0
+# RELAX-FIXUP: fixup A - offset: 0, value: %lo(foo), kind: fixup_riscv_lo12_s
+# RELAX-FIXUP: fixup B - offset: 0, value: 0, kind: fixup_riscv_relax
+
+auipc t1, %pcrel_hi(foo)
+# NORELAX-RELOC: R_RISCV_PCREL_HI20 foo 0x0
+# NORELAX-RELOC-NOT: R_RISCV_RELAX
+# RELOC: R_RISCV_PCREL_HI20 foo 0x0
+# RELAX-RELOC: R_RISCV_RELAX - 0x0
+# RELAX-FIXUP: fixup A - offset: 0, value: %pcrel_hi(foo), kind: fixup_riscv_pcrel_hi20
+# RELAX-FIXUP: fixup B - offset: 0, value: 0, kind: fixup_riscv_relax
+
+addi t1, t1, %pcrel_lo(foo)
+# NORELAX-RELOC: R_RISCV_PCREL_LO12_I foo 0x0
+# NORELAX-RELOC-NOT: R_RISCV_RELAX
+# RELOC: R_RISCV_PCREL_LO12_I foo 0x0
+# RELAX-RELOC: R_RISCV_RELAX - 0x0
+# RELAX-FIXUP: fixup A - offset: 0, value: %pcrel_lo(foo), kind: fixup_riscv_pcrel_lo12_i
+# RELAX-FIXUP: fixup B - offset: 0, value: 0, kind: fixup_riscv_relax
+
+sb t1, %pcrel_lo(foo)(a2)
+# NORELAX-RELOC: R_RISCV_PCREL_LO12_S foo 0x0
+# NORELAX-RELOC-NOT: R_RISCV_RELAX
+# RELOC: R_RISCV_PCREL_LO12_S foo 0x0
+# RELAX-RELOC: R_RISCV_RELAX - 0x0
+# RELAX-FIXUP: fixup A - offset: 0, value: %pcrel_lo(foo), kind: fixup_riscv_pcrel_lo12_s
+# RELAX-FIXUP: fixup B - offset: 0, value: 0, kind: fixup_riscv_relax

test/MC/RISCV/option-pushpop.s

@@ -21,7 +21,7 @@
 
 # CHECK-INST: call foo
 # CHECK-RELOC: R_RISCV_CALL foo 0x0
-# CHECK-RELOC-NOT: R_RISCV_RELAX foo 0x0
+# CHECK-RELOC-NOT: R_RISCV_RELAX - 0x0
 call foo
 
 # CHECK-INST: addi s0, sp, 1020
@@ -36,7 +36,7 @@ addi s0, sp, 1020
 # CHECK-INST: .option relax
 # CHECK-INST: call bar
 # CHECK-RELOC-NEXT: R_RISCV_CALL bar 0x0
-# CHECK-RELOC-NEXT: R_RISCV_RELAX bar 0x0
+# CHECK-RELOC-NEXT: R_RISCV_RELAX - 0x0
 call bar
 
 .option push    # Push relax=true, rvc=false
@@ -58,14 +58,14 @@ addi s0, sp, 1020
 
 # CHECK-INST: call bar
 # CHECK-RELOC-NEXT: R_RISCV_CALL bar 0x0
-# CHECK-RELOC-NEXT: R_RISCV_RELAX bar 0x0
+# CHECK-RELOC-NEXT: R_RISCV_RELAX - 0x0
 call bar
 
 .option pop     # Pop relax=false, rvc=false
 # CHECK-INST: .option pop
 # CHECK-INST: call baz
 # CHECK-RELOC: R_RISCV_CALL baz 0x0
-# CHECK-RELOC-NOT: R_RISCV_RELAX baz 0x0
+# CHECK-RELOC-NOT: R_RISCV_RELAX - 0x0
 call baz
 
 # CHECK-INST: addi s0, sp, 1020

test/MC/RISCV/option-relax.s

@@ -21,7 +21,7 @@
 
 # CHECK-INST: call foo
 # CHECK-RELOC: R_RISCV_CALL foo 0x0
-# CHECK-RELOC-NOT: R_RISCV_RELAX foo 0x0
+# CHECK-RELOC-NOT: R_RISCV_RELAX - 0x0
 call foo
 
 # CHECK-RELOC-NEXT: R_RISCV_ADD64
@@ -38,7 +38,7 @@ beq s1, s1, .L1
 
 # CHECK-INST: call bar
 # CHECK-RELOC-NEXT: R_RISCV_CALL bar 0x0
-# CHECK-RELOC-NEXT: R_RISCV_RELAX bar 0x0
+# CHECK-RELOC-NEXT: R_RISCV_RELAX - 0x0
 call bar
 
 # CHECK-RELOC-NEXT: R_RISCV_ADD64
@@ -54,7 +54,7 @@ beq s1, s1, .L1
 
 # CHECK-INST: call baz
 # CHECK-RELOC-NEXT: R_RISCV_CALL baz 0x0
-# CHECK-RELOC-NOT: R_RISCV_RELAX baz 0x0
+# CHECK-RELOC-NOT: R_RISCV_RELAX - 0x0
 call baz
 
 # CHECK-RELOC-NEXT: R_RISCV_ADD64