[MBP] Revert r231238 which attempted to fix a nasty bug where MBP is

just arbitrarily interleaving unrelated control flows once they get
moved "out-of-line" (both outside of natural CFG ordering and with
diamonds that cannot be fully laid out by chaining fallthrough edges).

This easy solution doesn't work in practice, and it isn't just a small
bug. It looks like a very different strategy will be required. I'm
working on that now, and it'll again go behind some flag so that
everyone can experiment and make sure it is working well for them.

llvm-svn: 231332

1 files changed, 9 insertions, 93 deletions

diff --git a/llvm/test/CodeGen/X86/block-placement.ll b/llvm/test/CodeGen/X86/block-placement.ll
index 49ee1b2c162..e0276e42d4d 100644
--- a/llvm/test/CodeGen/X86/block-placement.ll
+++ b/llvm/test/CodeGen/X86/block-placement.ll
@@ -1,4 +1,4 @@
-; RUN: llc -mtriple=i686-linux -place-last-successor -pre-RA-sched=source < %s | FileCheck %s
+; RUN: llc -mtriple=i686-linux -pre-RA-sched=source < %s | FileCheck %s
 
 declare void @error(i32 %i, i32 %a, i32 %b)
 
@@ -17,11 +17,11 @@ define i32 @test_ifchains(i32 %i, i32* %a, i32 %b) {
 ; CHECK: %else4
 ; CHECK-NOT: .align
 ; CHECK: %exit
-; CHECK: %then5
-; CHECK: %then4
-; CHECK: %then3
-; CHECK: %then2
 ; CHECK: %then1
+; CHECK: %then2
+; CHECK: %then3
+; CHECK: %then4
+; CHECK: %then5
 
 entry:
   %gep1 = getelementptr i32, i32* %a, i32 1
@@ -82,9 +82,9 @@ define i32 @test_loop_cold_blocks(i32 %i, i32* %a) {
 ; CHECK-LABEL: test_loop_cold_blocks:
 ; CHECK: %entry
 ; CHECK-NOT: .align
-; CHECK: %unlikely2
-; CHECK-NOT: .align
 ; CHECK: %unlikely1
+; CHECK-NOT: .align
+; CHECK: %unlikely2
 ; CHECK: .align
 ; CHECK: %body1
 ; CHECK: %body2
@@ -135,9 +135,9 @@ define i32 @test_loop_early_exits(i32 %i, i32* %a) {
 ; CHECK: %body3
 ; CHECK: %body4
 ; CHECK: %exit
-; CHECK: %bail3
-; CHECK: %bail2
 ; CHECK: %bail1
+; CHECK: %bail2
+; CHECK: %bail3
 
 entry:
   br label %body1
@@ -1083,87 +1083,3 @@ exit:
   %ret = phi i32 [ %val1, %then ], [ %val2, %else ]
   ret i32 %ret
 }
-
-define void @test_outlined() {
-; This test ends up with diamond control flow in outlined optional regions.
-; These diamonds should still be locally cohensive even when out-of-line due to
-; being cold.
-; CHECK-LABEL: test_outlined:
-; CHECK: %a1
-; CHECK: %a2
-; CHECK: %done
-; CHECK: %b2
-; CHECK: %c2
-; CHECK: %d2
-; CHECK: %f2
-; CHECK: %b1
-; CHECK: %c1
-; CHECK: %d1
-; CHECK: %f1
-
-a1:
-  %call.a1 = call i1 @a1()
-  br i1 %call.a1, label %b1, label %a2, !prof !0
-
-b1:
-  %call.b1 = call i1 @b1()
-  br i1 %call.b1, label %c1, label %d1
-
-c1:
-  call void @c1()
-  br label %f1
-
-d1:
-  call void @d1()
-  br label %f1
-
-f1:
-  call void @f1()
-  br label %a2
-
-a2:
-  %call.a2 = call i1 @a2()
-  br i1 %call.a2, label %b2, label %done, !prof !0
-
-b2:
-  %call.b2 = call i1 @b2()
-  br i1 %call.b2, label %c2, label %d2
-
-c2:
-  call void @c2()
-  br label %f2
-
-d2:
-  call void @d2()
-  br label %f2
-
-f2:
-  call void @f2()
-  br label %done
-
-done:
-  call void @done()
-  ret void
-}
-
-declare i1 @a1()
-
-declare i1 @b1()
-
-declare void @c1()
-
-declare void @d1()
-
-declare void @f1()
-
-declare i1 @a2()
-
-declare i1 @b2()
-
-declare void @c2()
-
-declare void @d2()
-
-declare void @f2()
-
-declare void @done()