2012-02-02 00:20:51 +01:00
|
|
|
; RUN: llc < %s -mcpu=generic -march=x86 | FileCheck %s
|
2008-02-21 08:42:26 +01:00
|
|
|
%struct._obstack_chunk = type { i8*, %struct._obstack_chunk*, [4 x i8] }
|
|
|
|
|
%struct.obstack = type { i32, %struct._obstack_chunk*, i8*, i8*, i8*, i32, i32, %struct._obstack_chunk* (...)*, void (...)*, i8*, i8 }
|
|
|
|
|
@stmt_obstack = external global %struct.obstack ; <%struct.obstack*> [#uses=1]
|
2006-09-06 23:54:59 +02:00
|
|
|
|
2010-01-07 22:59:23 +01:00
|
|
|
; This should just not crash.
|
|
|
|
|
define void @test1() nounwind {
|
2006-09-06 23:54:59 +02:00
|
|
|
entry:
|
2010-01-07 22:59:23 +01:00
|
|
|
br i1 true, label %cond_true, label %cond_next
|
2006-09-06 23:54:59 +02:00
|
|
|
|
|
|
|
|
cond_true: ; preds = %entry
|
2008-02-21 08:42:26 +01:00
|
|
|
%new_size.0.i = select i1 false, i32 0, i32 0 ; <i32> [#uses=1]
|
|
|
|
|
%tmp.i = load i32* bitcast (i8* getelementptr (%struct.obstack* @stmt_obstack, i32 0, i32 10) to i32*) ; <i32> [#uses=1]
|
|
|
|
|
%tmp.i.upgrd.1 = trunc i32 %tmp.i to i8 ; <i8> [#uses=1]
|
|
|
|
|
%tmp21.i = and i8 %tmp.i.upgrd.1, 1 ; <i8> [#uses=1]
|
|
|
|
|
%tmp22.i = icmp eq i8 %tmp21.i, 0 ; <i1> [#uses=1]
|
|
|
|
|
br i1 %tmp22.i, label %cond_false30.i, label %cond_true23.i
|
2006-09-06 23:54:59 +02:00
|
|
|
|
|
|
|
|
cond_true23.i: ; preds = %cond_true
|
|
|
|
|
ret void
|
|
|
|
|
|
|
|
|
|
cond_false30.i: ; preds = %cond_true
|
2008-02-21 08:42:26 +01:00
|
|
|
%tmp35.i = tail call %struct._obstack_chunk* null( i32 %new_size.0.i ) ; <%struct._obstack_chunk*> [#uses=0]
|
2006-09-06 23:54:59 +02:00
|
|
|
ret void
|
|
|
|
|
|
|
|
|
|
cond_next: ; preds = %entry
|
|
|
|
|
ret void
|
|
|
|
|
}
|
2010-01-07 22:59:23 +01:00
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
define i32 @test2(i16* %P, i16* %Q) nounwind {
|
|
|
|
|
%A = load i16* %P, align 4 ; <i16> [#uses=11]
|
|
|
|
|
%C = zext i16 %A to i32 ; <i32> [#uses=1]
|
|
|
|
|
%D = and i32 %C, 255 ; <i32> [#uses=1]
|
|
|
|
|
br label %L
|
|
|
|
|
L:
|
|
|
|
|
|
|
|
|
|
store i16 %A, i16* %Q
|
|
|
|
|
ret i32 %D
|
2013-10-16 01:33:07 +02:00
|
|
|
|
2013-07-13 22:38:47 +02:00
|
|
|
; CHECK-LABEL: test2:
|
2010-01-07 22:59:23 +01:00
|
|
|
; CHECK: movl 4(%esp), %eax
|
2013-10-16 01:33:07 +02:00
|
|
|
; CHECK-NEXT: movzwl (%eax), %e{{..}}
|
2010-01-07 22:59:23 +01:00
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
2012-08-02 02:56:42 +02:00
|
|
|
; rdar://10554090
|
|
|
|
|
; xor in exit block will be CSE'ed and load will be folded to xor in entry.
|
|
|
|
|
define i1 @test3(i32* %P, i32* %Q) nounwind {
|
2013-07-13 22:38:47 +02:00
|
|
|
; CHECK-LABEL: test3:
|
MachineSink: Fix and tweak critical-edge breaking heuristic.
Per original comment, the intention of this loop
is to go ahead and break the critical edge
(in order to sink this instruction) if there's
reason to believe doing so might "unblock" the
sinking of additional instructions that define
registers used by this one. The idea is that if
we have a few instructions to sink "together"
breaking the edge might be worthwhile.
This commit makes a few small changes
to help better realize this goal:
First, modify the loop to ignore registers
defined by this instruction. We don't
sink definitions of physical registers,
and sinking an SSA definition isn't
going to unblock an upstream instruction.
Second, ignore uses of physical registers.
Instructions that define physical registers are
rejected for sinking, and so moving this one
won't enable moving any defining instructions.
As an added bonus, while virtual register
use-def chains are generally small due
to SSA goodness, iteration over the uses
and definitions (used by hasOneNonDBGUse)
for physical registers like EFLAGS
can be rather expensive in practice.
(This is the original reason for looking at this)
Finally, to keep things simple continue
to only consider this trick for registers that
have a single use (via hasOneNonDBGUse),
but to avoid spuriously breaking critical edges
only do so if the definition resides
in the same MBB and therefore this one directly
blocks it from being sunk as well.
If sinking them together is meant to be,
let the iterative nature of this pass
sink the definition into this block first.
Update tests to accomodate this change,
add new testcase where sinking avoids pipeline stalls.
llvm-svn: 192608
2013-10-14 18:57:17 +02:00
|
|
|
; CHECK: movl 8(%esp), %e
|
|
|
|
|
; CHECK: movl 4(%esp), %e
|
|
|
|
|
; CHECK: xorl (%e
|
2012-08-02 02:56:42 +02:00
|
|
|
; CHECK: j
|
|
|
|
|
entry:
|
|
|
|
|
%0 = load i32* %P, align 4
|
|
|
|
|
%1 = load i32* %Q, align 4
|
|
|
|
|
%2 = xor i32 %0, %1
|
2012-08-18 19:53:03 +02:00
|
|
|
%3 = and i32 %2, 89947
|
2012-08-02 02:56:42 +02:00
|
|
|
%4 = icmp eq i32 %3, 0
|
|
|
|
|
br i1 %4, label %exit, label %land.end
|
|
|
|
|
|
|
|
|
|
exit:
|
|
|
|
|
%shr.i.i19 = xor i32 %1, %0
|
2012-08-18 19:53:03 +02:00
|
|
|
%5 = and i32 %shr.i.i19, 3456789123
|
2012-08-02 02:56:42 +02:00
|
|
|
%6 = icmp eq i32 %5, 0
|
|
|
|
|
br label %land.end
|
|
|
|
|
|
|
|
|
|
land.end:
|
|
|
|
|
%7 = phi i1 [ %6, %exit ], [ false, %entry ]
|
|
|
|
|
ret i1 %7
|
|
|
|
|
}
|
