Add pie as another relocation-model value

[hlopko]

MCP: rust-lang/compiler-team#461

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @wesleywiser (or someone else) soon.

Please see the contribution instructions for more information.

[rust-highfive]

⚠️ Warning ⚠️

• These commits modify compiler targets. (See the Target Tier Policy.)

[hlopko]

And I discovered a bug already - external functions should not be marked dso_local. I will add a fix and a test.

[wesleywiser]

r? @petrochenkov or @tmandry

[petrochenkov]

Also fn link_output_kind needs to be updated to treat pie in the same way as pic.

[petrochenkov]

r=me with commits squashed.

[hlopko]

(ftr, I believe I addressed all the comments, maybe I need to comment so bors continues with the r= command?)

[bjorn3]

The comments haven't been squashed into a single commit yet. Once that is done someone with review permission will need to tell bors to merge this PR.

[hlopko]

@bjorn3 are you saying that I should squash the commits? Or bors is going to do that?

[bjorn3]

You need to squash. Bors doesn't.

[hlopko]

I see, thank you! Done.

[bjorn3]

@bors r=petrochenkov

[bors]

📌 Commit d033e9b2c8d0eff1a49f4283f5c623c9503cdf10 has been approved by petrochenkov

[hlopko]

@bors r=petrochenkov

[bors]

@hlopko: 🔑 Insufficient privileges: Not in reviewers

[hlopko]

Had to try :)

[petrochenkov]

@bors r+

[bors]

📌 Commit dea3ee1 has been approved by petrochenkov

[Manishearth]

Failed in #89411 (comment) on x86_64-apple

@bors r-

---- [codegen] codegen/pie-relocation-model.rs stdout ----

error: verification with 'FileCheck' failed
status: exit status: 1
command: "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/llvm/build/bin/FileCheck" "--input-file" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/test/codegen/pie-relocation-model/pie-relocation-model.ll" "/Users/runner/work/rust/rust/src/test/codegen/pie-relocation-model.rs" "--allow-unused-prefixes" "--check-prefixes" "CHECK,NONMSVC"
stdout:
------------------------------------------

------------------------------------------
stderr:
------------------------------------------
/Users/runner/work/rust/rust/src/test/codegen/pie-relocation-model.rs:7:11: error: CHECK: expected string not found in input
// CHECK: define dso_local i8 @call_foreign_fn()
          ^
/Users/runner/work/rust/rust/build/x86_64-apple-darwin/test/codegen/pie-relocation-model/pie-relocation-model.ll:1:1: note: scanning from here
; ModuleID = 'pie_relocation_model.8d7ed54a-cgu.0'
^
/Users/runner/work/rust/rust/build/x86_64-apple-darwin/test/codegen/pie-relocation-model/pie-relocation-model.ll:9:10: note: possible intended match here
 %0 = tail call zeroext i8 @foreign_fn()
         ^

Input file: /Users/runner/work/rust/rust/build/x86_64-apple-darwin/test/codegen/pie-relocation-model/pie-relocation-model.ll
Check file: /Users/runner/work/rust/rust/src/test/codegen/pie-relocation-model.rs

-dump-input=help explains the following input dump.

Input was:
<<<<<<
           1: ; ModuleID = 'pie_relocation_model.8d7ed54a-cgu.0' 
check:7'0     X~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ error: no match found
           2: source_filename = "pie_relocation_model.8d7ed54a-cgu.0" 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
           3: target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
           4: target triple = "x86_64-apple-macosx10.8.0" 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
           5:  
check:7'0     ~
           6: ; Function Attrs: uwtable 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~
           7: define i8 @call_foreign_fn() unnamed_addr #0 { 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
           8: start: 
check:7'0     ~~~~~~~
           9:  %0 = tail call zeroext i8 @foreign_fn() 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
check:7'1              ?                                possible intended match
          10:  ret i8 %0 
check:7'0     ~~~~~~~~~~~
          11: } 
check:7'0     ~~
          12:  
check:7'0     ~
          13: ; Function Attrs: uwtable 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~
          14: declare zeroext i8 @foreign_fn() unnamed_addr #0 
check:7'0     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
           .
           .
           .
>>>>>>

------------------------------------------



failures:
    [codegen] codegen/pie-relocation-model.rs

[hlopko]

Restricted the codegen test only to x86_64 linux, the test doesn't make sense on mac as functions are (almost?) never marked dso_local there. And I don't know of PIE makes any sense for Windows.

[petrochenkov]

@bors r+

[bors]

📌 Commit 198d907 has been approved by petrochenkov