[mips] Enable tail calls by default

Enable tail calls by default for (micro)MIPS(64).

microMIPS is slightly more tricky than doing it for MIPS(R6) or microMIPSR6.
microMIPS has two instruction encodings: 16bit and 32bit along with some
restrictions on the size of the instruction that can fill the delay slot.
For safe tail calls for microMIPS, the delay slot filler attempts to find
a correct size instruction for the delay slot of TAILCALL pseudos.

Reviewers: dsanders, vkalintris

Subscribers: jfb, dsanders, sdardis, llvm-commits

Differential Revision: https://reviews.llvm.org/D21138

llvm-svn: 277708

1 files changed, 38 insertions, 20 deletions

diff --git a/llvm/test/CodeGen/Mips/llvm-ir/call.ll b/llvm/test/CodeGen/Mips/llvm-ir/call.ll
index 0d524d43960..1d0c76877dd 100644
--- a/llvm/test/CodeGen/Mips/llvm-ir/call.ll
+++ b/llvm/test/CodeGen/Mips/llvm-ir/call.ll
@@ -1,18 +1,29 @@
 ; Test the 'call' instruction and the tailcall variant.
 
-; FIXME: We should remove the need for -enable-mips-tail-calls
-; RUN: llc -march=mips   -mcpu=mips32   -relocation-model=pic -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,O32,NOT-R6C
-; RUN: llc -march=mips   -mcpu=mips32r2 -relocation-model=pic -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,O32,NOT-R6C
-; RUN: llc -march=mips   -mcpu=mips32r3 -relocation-model=pic -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,O32,NOT-R6C
-; RUN: llc -march=mips   -mcpu=mips32r5 -relocation-model=pic -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,O32,NOT-R6C
-; RUN: llc -march=mips   -mcpu=mips32r6 -relocation-model=pic -disable-mips-delay-filler -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,O32,R6C
-; RUN: llc -march=mips   -mcpu=mips32r6 -relocation-model=pic -mattr=+fp64,+nooddspreg -disable-mips-delay-filler -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,O32,R6C
-; RUN: llc -march=mips64 -mcpu=mips4    -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
-; RUN: llc -march=mips64 -mcpu=mips64   -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
-; RUN: llc -march=mips64 -mcpu=mips64r2 -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
-; RUN: llc -march=mips64 -mcpu=mips64r3 -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
-; RUN: llc -march=mips64 -mcpu=mips64r5 -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
-; RUN: llc -march=mips64 -mcpu=mips64r6 -disable-mips-delay-filler -enable-mips-tail-calls < %s | FileCheck %s -check-prefixes=ALL,N64,R6C
+; RUN: llc -march=mips   -mcpu=mips32   -relocation-model=pic  < %s | FileCheck %s -check-prefixes=ALL,O32,NOT-R6C
+; RUN: llc -march=mips   -mcpu=mips32r2 -relocation-model=pic  < %s | FileCheck %s -check-prefixes=ALL,O32,NOT-R6C
+; RUN: llc -march=mips   -mcpu=mips32r3 -relocation-model=pic  < %s | FileCheck %s -check-prefixes=ALL,O32,NOT-R6C
+; RUN: llc -march=mips   -mcpu=mips32r5 -relocation-model=pic  < %s | FileCheck %s -check-prefixes=ALL,O32,NOT-R6C
+; RUN: llc -march=mips   -mcpu=mips32r6 -relocation-model=pic -disable-mips-delay-filler  < %s | FileCheck %s -check-prefixes=ALL,O32,R6C
+; RUN: llc -march=mips   -mcpu=mips32r6 -relocation-model=pic -mattr=+fp64,+nooddspreg -disable-mips-delay-filler  < %s | FileCheck %s -check-prefixes=ALL,O32,R6C
+; RUN: llc -march=mips64 -mcpu=mips4     < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64    < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64r2  < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64r3  < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64r5  < %s | FileCheck %s -check-prefixes=ALL,N64,NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64r6 -disable-mips-delay-filler  < %s | FileCheck %s -check-prefixes=ALL,N64,R6C
+; RUN: llc -march=mips   -mcpu=mips32   -relocation-model=pic  < %s | FileCheck %s -check-prefix=ALL -check-prefix=O32 -check-prefix=NOT-R6C
+; RUN: llc -march=mips   -mcpu=mips32r2 -relocation-model=pic  < %s | FileCheck %s -check-prefix=ALL -check-prefix=O32 -check-prefix=NOT-R6C
+; RUN: llc -march=mips   -mcpu=mips32r3 -relocation-model=pic  < %s | FileCheck %s -check-prefix=ALL -check-prefix=O32 -check-prefix=NOT-R6C
+; RUN: llc -march=mips   -mcpu=mips32r5 -relocation-model=pic  < %s | FileCheck %s -check-prefix=ALL -check-prefix=O32 -check-prefix=NOT-R6C
+; RUN: llc -march=mips   -mcpu=mips32r6 -relocation-model=pic -disable-mips-delay-filler  < %s | FileCheck %s -check-prefix=ALL -check-prefix=O32 -check-prefix=R6C
+; RUN: llc -march=mips   -mcpu=mips32r6 -relocation-model=pic -mattr=+fp64,+nooddspreg -disable-mips-delay-filler  < %s | FileCheck %s -check-prefix=ALL -check-prefix=O32 -check-prefix=R6C
+; RUN: llc -march=mips64 -mcpu=mips4     < %s | FileCheck %s -check-prefix=ALL -check-prefix=N64 -check-prefix=NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64    < %s | FileCheck %s -check-prefix=ALL -check-prefix=N64 -check-prefix=NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64r2  < %s | FileCheck %s -check-prefix=ALL -check-prefix=N64 -check-prefix=NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64r3  < %s | FileCheck %s -check-prefix=ALL -check-prefix=N64 -check-prefix=NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64r5  < %s | FileCheck %s -check-prefix=ALL -check-prefix=N64 -check-prefix=NOT-R6C
+; RUN: llc -march=mips64 -mcpu=mips64r6 -disable-mips-delay-filler  < %s | FileCheck %s -check-prefix=ALL -check-prefix=N64 -check-prefix=R6C
 
 declare void @extern_void_void()
 declare i32 @extern_i32_void()
@@ -76,7 +87,8 @@ define void @musttail_call_void_void() {
 
 ; N64:           ld $[[TGT:[0-9]+]], %call16(extern_void_void)($gp)
 
-; ALL:           jr $[[TGT]]
+; NOT-R6C:       jr   $[[TGT]]
+; R6C:           jrc  $[[TGT]]
 
   musttail call void @extern_void_void()
   ret void
@@ -89,7 +101,8 @@ define i32 @musttail_call_i32_void() {
 
 ; N64:           ld $[[TGT:[0-9]+]], %call16(extern_i32_void)($gp)
 
-; ALL:           jr $[[TGT]]
+; NOT-R6C:       jr   $[[TGT]]
+; R6C:           jrc  $[[TGT]]
 
   %1 = musttail call i32 @extern_i32_void()
   ret i32 %1
@@ -102,7 +115,8 @@ define float @musttail_call_float_void() {
 
 ; N64:           ld $[[TGT:[0-9]+]], %call16(extern_float_void)($gp)
 
-; ALL:           jr $[[TGT]]
+; NOT-R6C:       jr   $[[TGT]]
+; R6C:           jrc  $[[TGT]]
 
   %1 = musttail call float @extern_float_void()
   ret float %1
@@ -154,7 +168,8 @@ define void @tail_indirect_call_void_void(void ()* %addr) {
 ; ALL-LABEL: tail_indirect_call_void_void:
 
 ; ALL:           move $25, $4
-; ALL:           jr $25
+; NOT-R6C:       jr   $[[TGT]]
+; R6C:           jrc  $[[TGT]]
 
   tail call void %addr()
   ret void
@@ -164,7 +179,8 @@ define i32 @tail_indirect_call_i32_void(i32 ()* %addr) {
 ; ALL-LABEL: tail_indirect_call_i32_void:
 
 ; ALL:           move $25, $4
-; ALL:           jr $25
+; NOT-R6C:       jr   $[[TGT]]
+; R6C:           jrc  $[[TGT]]
 
   %1 = tail call i32 %addr()
   ret i32 %1
@@ -174,7 +190,8 @@ define float @tail_indirect_call_float_void(float ()* %addr) {
 ; ALL-LABEL: tail_indirect_call_float_void:
 
 ; ALL:           move $25, $4
-; ALL:           jr $25
+; NOT-R6C:       jr   $[[TGT]]
+; R6C:           jrc  $[[TGT]]
 
   %1 = tail call float %addr()
   ret float %1
@@ -188,7 +205,8 @@ define hidden void @thunk_undef_double(i32 %this, double %volume) unnamed_addr a
 ; ALL-LABEL: thunk_undef_double:
 ; O32: # implicit-def: %A2
 ; O32: # implicit-def: %A3
-; ALL:        jr $25
+; NOT-R6C:    jr   $[[TGT]]
+; R6C:        jrc  $[[TGT]]
 
   tail call void @undef_double(i32 undef, double undef) #8
   ret void