diff options
Diffstat (limited to 'llvm/test/CodeGen/X86/block-placement.ll')
| -rw-r--r-- | llvm/test/CodeGen/X86/block-placement.ll | 27 |
1 files changed, 13 insertions, 14 deletions
diff --git a/llvm/test/CodeGen/X86/block-placement.ll b/llvm/test/CodeGen/X86/block-placement.ll index 2b16e417385..98d37153876 100644 --- a/llvm/test/CodeGen/X86/block-placement.ll +++ b/llvm/test/CodeGen/X86/block-placement.ll @@ -463,23 +463,26 @@ exit: } define void @fpcmp_unanalyzable_branch(i1 %cond) { -; This function's CFG contains an once-unanalyzable branch (une on floating -; points). As now it becomes analyzable, we should get best layout in which each -; edge in 'entry' -> 'entry.if.then_crit_edge' -> 'if.then' -> 'if.end' is -; fall-through. +; This function's CFG contains an unanalyzable branch that is likely to be +; split due to having a different high-probability predecessor. ; CHECK: fpcmp_unanalyzable_branch ; CHECK: %entry -; CHECK: %entry.if.then_crit_edge -; CHECK: %if.then -; CHECK: %if.end ; CHECK: %exit +; CHECK-NOT: %if.then +; CHECK-NOT: %if.end +; CHECK-NOT: jne +; CHECK-NOT: jnp ; CHECK: jne ; CHECK-NEXT: jnp +; CHECK-NEXT: %if.then entry: ; Note that this branch must be strongly biased toward ; 'entry.if.then_crit_edge' to ensure that we would try to form a chain for -; 'entry' -> 'entry.if.then_crit_edge' -> 'if.then' -> 'if.end'. +; 'entry' -> 'entry.if.then_crit_edge' -> 'if.then'. It is the last edge in that +; chain which would violate the unanalyzable branch in 'exit', but we won't even +; try this trick unless 'if.then' is believed to almost always be reached from +; 'entry.if.then_crit_edge'. br i1 %cond, label %entry.if.then_crit_edge, label %lor.lhs.false, !prof !1 entry.if.then_crit_edge: @@ -491,7 +494,7 @@ lor.lhs.false: exit: %cmp.i = fcmp une double 0.000000e+00, undef - br i1 %cmp.i, label %if.then, label %if.end, !prof !3 + br i1 %cmp.i, label %if.then, label %if.end if.then: %0 = phi i8 [ %.pre14, %entry.if.then_crit_edge ], [ undef, %exit ] @@ -504,7 +507,6 @@ if.end: } !1 = !{!"branch_weights", i32 1000, i32 1} -!3 = !{!"branch_weights", i32 1, i32 1000} declare i32 @f() declare i32 @g() @@ -663,14 +665,11 @@ define void @unanalyzable_branch_to_best_succ(i1 %cond) { ; Ensure that we can handle unanalyzable branches where the destination block ; gets selected as the optimal successor to merge. ; -; This branch is now analyzable and hence the destination block becomes the -; hotter one. The right order is entry->bar->exit->foo. -; ; CHECK: unanalyzable_branch_to_best_succ ; CHECK: %entry +; CHECK: %foo ; CHECK: %bar ; CHECK: %exit -; CHECK: %foo entry: ; Bias this branch toward bar to ensure we form that chain. |
