[PATCH] D38554: Fixed ppc32 function relocations in non-pic mode

[vit9696 via Phabricator via llvm-commits]

vit9696 updated this revision to Diff 119839.
vit9696 added a comment.

Alright, now I understand that the condition I added in the beginning did not conform to all the other relocation models available in LLVM:

  -relocation-model                                 - Choose relocation model
    =static                                         -   Non-relocatable code
    =pic                                            -   Fully relocatable, position independent code
    =dynamic-no-pic                                 -   Relocatable external references, non-relocatable code
    =ropi                                           -   Code and read-only data relocatable, accessed PC-relative
    =rwpi                                           -   Read-write data relocatable, accessed relative to static base
    =ropi-rwpi                                      -   Combination of ropi and rwpi

Initially I added PLT to be enabled only for PIC model, and you are right, in case of dynamic-no-pic model (which allows dynamic relocation) PLT must be used. I updated the diff to enable PLT unless static relocation model is used. No issues from then on?


https://reviews.llvm.org/D38554

Files:
  lib/Target/PowerPC/PPCISelLowering.cpp
  test/CodeGen/PowerPC/ppc32-static.ll


Index: test/CodeGen/PowerPC/ppc32-static.ll
===================================================================
--- test/CodeGen/PowerPC/ppc32-static.ll
+++ test/CodeGen/PowerPC/ppc32-static.ll
@@ -0,0 +1,13 @@
+; RUN: llc < %s -mtriple=powerpc-unknown-linux-gnu -relocation-model=static | FileCheck --match-full-lines %s
+
+declare i32 @call_foo(i32, ...)
+
+define i32 @foo() {
+entry:
+  %call = call i32 (i32, ...) @call_foo(i32 0, i32 1)
+  ret i32 0
+}
+
+; LABEL:foo:
+; CHECK-NOT:  bl call_foo at PLT
+; CHECK:      bl call_foo
Index: lib/Target/PowerPC/PPCISelLowering.cpp
===================================================================
--- lib/Target/PowerPC/PPCISelLowering.cpp
+++ lib/Target/PowerPC/PPCISelLowering.cpp
@@ -4719,7 +4719,8 @@
   if (auto *G = dyn_cast<GlobalAddressSDNode>(Callee))
     GV = G->getGlobal();
   bool Local = TM.shouldAssumeDSOLocal(*Mod, GV);
-  bool UsePlt = !Local && Subtarget.isTargetELF() && !isPPC64;
+  bool UsePlt = !Local && Subtarget.isTargetELF() && !isPPC64 &&
+                DAG.getTarget().getRelocationModel() != Reloc::Static;
 
   if (isFunctionGlobalAddress(Callee)) {
     GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Callee);


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