[RISCV] Properly evaluate fixup_riscv_pcrel_lo12

This is a update to D43157 to correctly handle fixup_riscv_pcrel_lo12.

Notable changes:

Rebased onto trunk
Handle and test S-type
Test case pcrel-hilo.s is merged into relocations.s

D43157 description:
VK_RISCV_PCREL_LO has to be handled specially. The MCExpr inside is
actually the location of an auipc instruction with a VK_RISCV_PCREL_HI fixup
pointing to the real target.

Differential Revision: https://reviews.llvm.org/D54029
Patch by Chih-Mao Chen and Michael Spencer.

llvm-svn: 349764

3 files changed, 27 insertions, 20 deletions

diff --git a/llvm/test/MC/RISCV/fixups.s b/llvm/test/MC/RISCV/fixups.s
index 0f5432dd117..f0377debabb 100644
--- a/llvm/test/MC/RISCV/fixups.s
+++ b/llvm/test/MC/RISCV/fixups.s
@@ -24,15 +24,26 @@ sw a0, %lo(val)(t1)
 # CHECK-FIXUP: fixup A - offset: 0, value: %lo(val), kind: fixup_riscv_lo12_s
 # CHECK-INSTR: sw a0, 1656(t1)
 
+1:
+auipc t1, %pcrel_hi(.LBB0)
+# CHECK-FIXUP: fixup A - offset: 0, value: %pcrel_hi(.LBB0), kind: fixup_riscv_pcrel_hi20
+# CHECK-INSTR: auipc t1, 0
+addi t1, t1, %pcrel_lo(1b)
+# CHECK-FIXUP: fixup A - offset: 0, value: %pcrel_lo(.Ltmp0), kind: fixup_riscv_pcrel_lo12_i
+# CHECK-INSTR: addi t1, t1, -16
+sw t1, %pcrel_lo(1b)(t1)
+# CHECK-FIXUP: fixup A - offset: 0, value: %pcrel_lo(.Ltmp0), kind: fixup_riscv_pcrel_lo12_s
+# CHECK-INSTR: sw t1, -16(t1)
+
 jal zero, .LBB0
 # CHECK-FIXUP: fixup A - offset: 0, value: .LBB0, kind: fixup_riscv_jal
-# CHECK-INSTR: jal zero, -16
+# CHECK-INSTR: jal zero, -28
 jal zero, .LBB2
 # CHECK-FIXUP: fixup A - offset: 0, value: .LBB2, kind: fixup_riscv_jal
 # CHECK-INSTR: jal zero, 330996
 beq a0, a1, .LBB0
 # CHECK-FIXUP: fixup A - offset: 0, value: .LBB0, kind: fixup_riscv_branch
-# CHECK-INSTR: beq a0, a1, -24
+# CHECK-INSTR: beq a0, a1, -36
 blt a0, a1, .LBB1
 # CHECK-FIXUP: fixup A - offset: 0, value: .LBB1, kind: fixup_riscv_branch
 # CHECK-INSTR: blt a0, a1, 1108
diff --git a/llvm/test/MC/RISCV/pcrel-lo12-invalid.s b/llvm/test/MC/RISCV/pcrel-lo12-invalid.s
new file mode 100644
index 00000000000..7cf2494ad8e
--- /dev/null
+++ b/llvm/test/MC/RISCV/pcrel-lo12-invalid.s
@@ -0,0 +1,5 @@
+# RUN: not llvm-mc -triple riscv32 -mattr=-relax -filetype obj < %s -o /dev/null 2>&1 | FileCheck %s
+# RUN: not llvm-mc -triple riscv32 -mattr=+relax -filetype obj < %s -o /dev/null 2>&1 | FileCheck %s
+
+1:
+  addi a0, a0, %pcrel_lo(1b) # CHECK: :[[@LINE]]:3: error: could not find corresponding %pcrel_hi
diff --git a/llvm/test/MC/RISCV/relocations.s b/llvm/test/MC/RISCV/relocations.s
index b68b11bf195..a879c9a54ad 100644
--- a/llvm/test/MC/RISCV/relocations.s
+++ b/llvm/test/MC/RISCV/relocations.s
@@ -44,6 +44,7 @@ sb t1, %lo(foo+4)(a2)
 # INSTR: sb t1, %lo(foo+4)(a2)
 # FIXUP: fixup A - offset: 0, value: %lo(foo+4), kind: fixup_riscv_lo12_s
 
+.L0:
 auipc t1, %pcrel_hi(foo)
 # RELOC: R_RISCV_PCREL_HI20 foo 0x0
 # INSTR: auipc t1, %pcrel_hi(foo)
@@ -54,25 +55,15 @@ auipc t1, %pcrel_hi(foo+4)
 # INSTR: auipc t1, %pcrel_hi(foo+4)
 # FIXUP: fixup A - offset: 0, value: %pcrel_hi(foo+4), kind: fixup_riscv_pcrel_hi20
 
-addi t1, t1, %pcrel_lo(foo)
-# RELOC: R_RISCV_PCREL_LO12_I foo 0x0
-# INSTR: addi t1, t1, %pcrel_lo(foo)
-# FIXUP: fixup A - offset: 0, value: %pcrel_lo(foo), kind: fixup_riscv_pcrel_lo12_i
+addi t1, t1, %pcrel_lo(.L0)
+# RELOC: R_RISCV_PCREL_LO12_I .L0 0x0
+# INSTR: addi t1, t1, %pcrel_lo(.L0)
+# FIXUP: fixup A - offset: 0, value: %pcrel_lo(.L0), kind: fixup_riscv_pcrel_lo12_i
 
-addi t1, t1, %pcrel_lo(foo+4)
-# RELOC: R_RISCV_PCREL_LO12_I foo 0x4
-# INSTR: addi t1, t1, %pcrel_lo(foo+4)
-# FIXUP: fixup A - offset: 0, value: %pcrel_lo(foo+4), kind: fixup_riscv_pcrel_lo12_i
-
-sb t1, %pcrel_lo(foo)(a2)
-# RELOC: R_RISCV_PCREL_LO12_S foo 0x0
-# INSTR: sb t1, %pcrel_lo(foo)(a2)
-# FIXUP: fixup A - offset: 0, value: %pcrel_lo(foo), kind: fixup_riscv_pcrel_lo12_s
-
-sb t1, %pcrel_lo(foo+4)(a2)
-# RELOC: R_RISCV_PCREL_LO12_S foo 0x4
-# INSTR: sb t1, %pcrel_lo(foo+4)(a2)
-# FIXUP: fixup A - offset: 0, value: %pcrel_lo(foo+4), kind: fixup_riscv_pcrel_lo12_s
+sb t1, %pcrel_lo(.L0)(a2)
+# RELOC: R_RISCV_PCREL_LO12_S .L0 0x0
+# INSTR: sb t1, %pcrel_lo(.L0)(a2)
+# FIXUP: fixup A - offset: 0, value: %pcrel_lo(.L0), kind: fixup_riscv_pcrel_lo12_s
 
 jal zero, foo
 # RELOC: R_RISCV_JAL