mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-24 11:42:57 +01:00
e3e67d4a0a
This changes the SelectionDAG scheduling preference to source order. Soon, the SelectionDAG scheduler can be bypassed saving a nice chunk of compile time. Performance differences that result from this change are often a consequence of register coalescing. The register coalescer is far from perfect. Bugs can be filed for deficiencies. On x86 SandyBridge/Haswell, the source order schedule is often preserved, particularly for small blocks. Register pressure is generally improved over the SD scheduler's ILP mode. However, we are still able to handle large blocks that require latency hiding, unlike the SD scheduler's BURR mode. MI scheduler also attempts to discover the critical path in single-block loops and adjust heuristics accordingly. The MI scheduler relies on the new machine model. This is currently unimplemented for AVX, so we may not be generating the best code yet. Unit tests are updated so they don't depend on SD scheduling heuristics. llvm-svn: 192750
28 lines
815 B
LLVM
28 lines
815 B
LLVM
; RUN: llc < %s -mtriple=i386-unknown-linux-gnu -mcpu=corei7-avx -enable-misched=false | FileCheck %s
|
|
|
|
; CHECK-LABEL: main:
|
|
; CHECK: pushl %esi
|
|
; CHECK-NEXT: movl $-12, %eax
|
|
; CHECK-NEXT: movl $-1, %edx
|
|
; CHECK-NEXT: testb $1, 8(%esp)
|
|
; CHECK-NEXT: cmovel %edx, %eax
|
|
; CHECK-NEXT: xorl %ecx, %ecx
|
|
; CHECK-NEXT: movl %eax, %esi
|
|
; CHECK-NEXT: addl $-1, %esi
|
|
; CHECK-NEXT: movl $-1, %esi
|
|
; CHECK-NEXT: adcl $-1, %esi
|
|
; CHECK-NEXT: cmovsl %ecx, %eax
|
|
; CHECK-NEXT: cmovsl %ecx, %edx
|
|
; CHECK-NEXT: popl %esi
|
|
define i64 @main(i1 %tobool1) nounwind {
|
|
entry:
|
|
%0 = zext i1 %tobool1 to i32
|
|
%. = xor i32 %0, 1
|
|
%.21 = select i1 %tobool1, i32 -12, i32 -1
|
|
%conv = sext i32 %.21 to i64
|
|
%1 = add i64 %conv, -1
|
|
%cmp10 = icmp slt i64 %1, 0
|
|
%sub17 = select i1 %cmp10, i64 0, i64 %conv
|
|
ret i64 %sub17
|
|
}
|