[RISCV] Lower calls through PLT

This patch adds support for generating calls through the procedure
linkage table where required for a given ExternalSymbol or GlobalAddress
callee.

Differential Revision: https://reviews.llvm.org/D55304

llvm-svn: 363686

1 files changed, 124 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/RISCV/calls.ll b/llvm/test/CodeGen/RISCV/calls.ll
index 413b61d70b0..801b298da0d 100644
--- a/llvm/test/CodeGen/RISCV/calls.ll
+++ b/llvm/test/CodeGen/RISCV/calls.ll
@@ -1,6 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc -mtriple=riscv32 -verify-machineinstrs < %s \
 ; RUN:   | FileCheck -check-prefix=RV32I %s
+; RUN: llc -relocation-model=pic -mtriple=riscv32 -verify-machineinstrs < %s \
+; RUN:   | FileCheck -check-prefix=RV32I-PIC %s
 
 declare i32 @external_function(i32)
 
@@ -13,15 +15,53 @@ define i32 @test_call_external(i32 %a) nounwind {
 ; RV32I-NEXT:    lw ra, 12(sp)
 ; RV32I-NEXT:    addi sp, sp, 16
 ; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: test_call_external:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    addi sp, sp, -16
+; RV32I-PIC-NEXT:    sw ra, 12(sp)
+; RV32I-PIC-NEXT:    call external_function@plt
+; RV32I-PIC-NEXT:    lw ra, 12(sp)
+; RV32I-PIC-NEXT:    addi sp, sp, 16
+; RV32I-PIC-NEXT:    ret
   %1 = call i32 @external_function(i32 %a)
   ret i32 %1
 }
 
+declare dso_local i32 @dso_local_function(i32)
+
+define i32 @test_call_dso_local(i32 %a) nounwind {
+; RV32I-LABEL: test_call_dso_local:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    addi sp, sp, -16
+; RV32I-NEXT:    sw ra, 12(sp)
+; RV32I-NEXT:    call dso_local_function
+; RV32I-NEXT:    lw ra, 12(sp)
+; RV32I-NEXT:    addi sp, sp, 16
+; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: test_call_dso_local:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    addi sp, sp, -16
+; RV32I-PIC-NEXT:    sw ra, 12(sp)
+; RV32I-PIC-NEXT:    call dso_local_function
+; RV32I-PIC-NEXT:    lw ra, 12(sp)
+; RV32I-PIC-NEXT:    addi sp, sp, 16
+; RV32I-PIC-NEXT:    ret
+  %1 = call i32 @dso_local_function(i32 %a)
+  ret i32 %1
+}
+
 define i32 @defined_function(i32 %a) nounwind {
 ; RV32I-LABEL: defined_function:
 ; RV32I:       # %bb.0:
 ; RV32I-NEXT:    addi a0, a0, 1
 ; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: defined_function:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    addi a0, a0, 1
+; RV32I-PIC-NEXT:    ret
   %1 = add i32 %a, 1
   ret i32 %1
 }
@@ -35,6 +75,15 @@ define i32 @test_call_defined(i32 %a) nounwind {
 ; RV32I-NEXT:    lw ra, 12(sp)
 ; RV32I-NEXT:    addi sp, sp, 16
 ; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: test_call_defined:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    addi sp, sp, -16
+; RV32I-PIC-NEXT:    sw ra, 12(sp)
+; RV32I-PIC-NEXT:    call defined_function@plt
+; RV32I-PIC-NEXT:    lw ra, 12(sp)
+; RV32I-PIC-NEXT:    addi sp, sp, 16
+; RV32I-PIC-NEXT:    ret
   %1 = call i32 @defined_function(i32 %a)
   ret i32 %1
 }
@@ -50,6 +99,17 @@ define i32 @test_call_indirect(i32 (i32)* %a, i32 %b) nounwind {
 ; RV32I-NEXT:    lw ra, 12(sp)
 ; RV32I-NEXT:    addi sp, sp, 16
 ; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: test_call_indirect:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    addi sp, sp, -16
+; RV32I-PIC-NEXT:    sw ra, 12(sp)
+; RV32I-PIC-NEXT:    mv a2, a0
+; RV32I-PIC-NEXT:    mv a0, a1
+; RV32I-PIC-NEXT:    jalr a2
+; RV32I-PIC-NEXT:    lw ra, 12(sp)
+; RV32I-PIC-NEXT:    addi sp, sp, 16
+; RV32I-PIC-NEXT:    ret
   %1 = call i32 %a(i32 %b)
   ret i32 %1
 }
@@ -62,6 +122,11 @@ define fastcc i32 @fastcc_function(i32 %a, i32 %b) nounwind {
 ; RV32I:       # %bb.0:
 ; RV32I-NEXT:    add a0, a0, a1
 ; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: fastcc_function:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    add a0, a0, a1
+; RV32I-PIC-NEXT:    ret
  %1 = add i32 %a, %b
  ret i32 %1
 }
@@ -79,6 +144,19 @@ define i32 @test_call_fastcc(i32 %a, i32 %b) nounwind {
 ; RV32I-NEXT:    lw ra, 12(sp)
 ; RV32I-NEXT:    addi sp, sp, 16
 ; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: test_call_fastcc:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    addi sp, sp, -16
+; RV32I-PIC-NEXT:    sw ra, 12(sp)
+; RV32I-PIC-NEXT:    sw s0, 8(sp)
+; RV32I-PIC-NEXT:    mv s0, a0
+; RV32I-PIC-NEXT:    call fastcc_function@plt
+; RV32I-PIC-NEXT:    mv a0, s0
+; RV32I-PIC-NEXT:    lw s0, 8(sp)
+; RV32I-PIC-NEXT:    lw ra, 12(sp)
+; RV32I-PIC-NEXT:    addi sp, sp, 16
+; RV32I-PIC-NEXT:    ret
   %1 = call fastcc i32 @fastcc_function(i32 %a, i32 %b)
   ret i32 %a
 }
@@ -107,6 +185,28 @@ define i32 @test_call_external_many_args(i32 %a) nounwind {
 ; RV32I-NEXT:    lw ra, 12(sp)
 ; RV32I-NEXT:    addi sp, sp, 16
 ; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: test_call_external_many_args:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    addi sp, sp, -16
+; RV32I-PIC-NEXT:    sw ra, 12(sp)
+; RV32I-PIC-NEXT:    sw s0, 8(sp)
+; RV32I-PIC-NEXT:    mv s0, a0
+; RV32I-PIC-NEXT:    sw a0, 4(sp)
+; RV32I-PIC-NEXT:    sw a0, 0(sp)
+; RV32I-PIC-NEXT:    mv a1, a0
+; RV32I-PIC-NEXT:    mv a2, a0
+; RV32I-PIC-NEXT:    mv a3, a0
+; RV32I-PIC-NEXT:    mv a4, a0
+; RV32I-PIC-NEXT:    mv a5, a0
+; RV32I-PIC-NEXT:    mv a6, a0
+; RV32I-PIC-NEXT:    mv a7, a0
+; RV32I-PIC-NEXT:    call external_many_args@plt
+; RV32I-PIC-NEXT:    mv a0, s0
+; RV32I-PIC-NEXT:    lw s0, 8(sp)
+; RV32I-PIC-NEXT:    lw ra, 12(sp)
+; RV32I-PIC-NEXT:    addi sp, sp, 16
+; RV32I-PIC-NEXT:    ret
   %1 = call i32 @external_many_args(i32 %a, i32 %a, i32 %a, i32 %a, i32 %a,
                                     i32 %a, i32 %a, i32 %a, i32 %a, i32 %a)
   ret i32 %a
@@ -118,6 +218,12 @@ define i32 @defined_many_args(i32, i32, i32, i32, i32, i32, i32, i32, i32, i32 %
 ; RV32I-NEXT:    lw a0, 4(sp)
 ; RV32I-NEXT:    addi a0, a0, 1
 ; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: defined_many_args:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    lw a0, 4(sp)
+; RV32I-PIC-NEXT:    addi a0, a0, 1
+; RV32I-PIC-NEXT:    ret
   %added = add i32 %j, 1
   ret i32 %added
 }
@@ -140,6 +246,24 @@ define i32 @test_call_defined_many_args(i32 %a) nounwind {
 ; RV32I-NEXT:    lw ra, 12(sp)
 ; RV32I-NEXT:    addi sp, sp, 16
 ; RV32I-NEXT:    ret
+;
+; RV32I-PIC-LABEL: test_call_defined_many_args:
+; RV32I-PIC:       # %bb.0:
+; RV32I-PIC-NEXT:    addi sp, sp, -16
+; RV32I-PIC-NEXT:    sw ra, 12(sp)
+; RV32I-PIC-NEXT:    sw a0, 4(sp)
+; RV32I-PIC-NEXT:    sw a0, 0(sp)
+; RV32I-PIC-NEXT:    mv a1, a0
+; RV32I-PIC-NEXT:    mv a2, a0
+; RV32I-PIC-NEXT:    mv a3, a0
+; RV32I-PIC-NEXT:    mv a4, a0
+; RV32I-PIC-NEXT:    mv a5, a0
+; RV32I-PIC-NEXT:    mv a6, a0
+; RV32I-PIC-NEXT:    mv a7, a0
+; RV32I-PIC-NEXT:    call defined_many_args@plt
+; RV32I-PIC-NEXT:    lw ra, 12(sp)
+; RV32I-PIC-NEXT:    addi sp, sp, 16
+; RV32I-PIC-NEXT:    ret
   %1 = call i32 @defined_many_args(i32 %a, i32 %a, i32 %a, i32 %a, i32 %a,
                                    i32 %a, i32 %a, i32 %a, i32 %a, i32 %a)
   ret i32 %1