llvm-6502/test/CodeGen/X86/sink-hoist.ll
Andrew Trick 6a7770b7ae Enable MI Sched for x86.
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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192750 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-15 23:33:07 +00:00

175 lines
7.2 KiB
LLVM

; RUN: llc < %s -march=x86-64 -asm-verbose=false -mtriple=x86_64-unknown-linux-gnu -mcpu=nehalem -post-RA-scheduler=true -schedmodel=false | FileCheck %s
; Currently, floating-point selects are lowered to CFG triangles.
; This means that one side of the select is always unconditionally
; evaluated, however with MachineSink we can sink the other side so
; that it's conditionally evaluated.
; CHECK-LABEL: foo:
; CHECK-NEXT: testb $1, %dil
; CHECK-NEXT: jne
; CHECK-NEXT: divsd
; CHECK-NEXT: movaps
; CHECK-NEXT: ret
; CHECK: divsd
define double @foo(double %x, double %y, i1 %c) nounwind {
%a = fdiv double %x, 3.2
%b = fdiv double %y, 3.3
%z = select i1 %c, double %a, double %b
ret double %z
}
; Make sure the critical edge is broken so the divsd is sunken below
; the conditional branch.
; rdar://8454886
; CHECK-LABEL: split:
; CHECK-NEXT: testb $1, %dil
; CHECK-NEXT: je
; CHECK: divsd
; CHECK: movaps
; CHECK: ret
define double @split(double %x, double %y, i1 %c) nounwind {
%a = fdiv double %x, 3.2
%z = select i1 %c, double %a, double %y
ret double %z
}
; Hoist floating-point constant-pool loads out of loops.
; CHECK-LABEL: bar:
; CHECK: movsd
; CHECK: align
define void @bar(double* nocapture %p, i64 %n) nounwind {
entry:
%0 = icmp sgt i64 %n, 0
br i1 %0, label %bb, label %return
bb:
%i.03 = phi i64 [ 0, %entry ], [ %3, %bb ]
%scevgep = getelementptr double* %p, i64 %i.03
%1 = load double* %scevgep, align 8
%2 = fdiv double 3.200000e+00, %1
store double %2, double* %scevgep, align 8
%3 = add nsw i64 %i.03, 1
%exitcond = icmp eq i64 %3, %n
br i1 %exitcond, label %return, label %bb
return:
ret void
}
; Sink instructions with dead EFLAGS defs.
; FIXME: Unfail the zzz test if we can correctly mark pregs with the kill flag.
;
; See <rdar://problem/8030636>. This test isn't valid after we made machine
; sinking more conservative about sinking instructions that define a preg into a
; block when we don't know if the preg is killed within the current block.
; FIXMEHECK: zzz:
; FIXMEHECK: je
; FIXMEHECK-NEXT: orb
; define zeroext i8 @zzz(i8 zeroext %a, i8 zeroext %b) nounwind readnone {
; entry:
; %tmp = zext i8 %a to i32 ; <i32> [#uses=1]
; %tmp2 = icmp eq i8 %a, 0 ; <i1> [#uses=1]
; %tmp3 = or i8 %b, -128 ; <i8> [#uses=1]
; %tmp4 = and i8 %b, 127 ; <i8> [#uses=1]
; %b_addr.0 = select i1 %tmp2, i8 %tmp4, i8 %tmp3 ; <i8> [#uses=1]
; ret i8 %b_addr.0
; }
; Codegen should hoist and CSE these constants.
; CHECK-LABEL: vv:
; CHECK: LCPI3_0(%rip), %xmm0
; CHECK: LCPI3_1(%rip), %xmm1
; CHECK: LCPI3_2(%rip), %xmm2
; CHECK: align
; CHECK-NOT: LCPI
; CHECK: ret
@_minusZero.6007 = internal constant <4 x float> <float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00> ; <<4 x float>*> [#uses=0]
@twoTo23.6008 = internal constant <4 x float> <float 8.388608e+06, float 8.388608e+06, float 8.388608e+06, float 8.388608e+06> ; <<4 x float>*> [#uses=0]
define void @vv(float* %y, float* %x, i32* %n) nounwind ssp {
entry:
br label %bb60
bb: ; preds = %bb60
%i.0 = phi i32 [ 0, %bb60 ] ; <i32> [#uses=2]
%0 = bitcast float* %x_addr.0 to <4 x float>* ; <<4 x float>*> [#uses=1]
%1 = load <4 x float>* %0, align 16 ; <<4 x float>> [#uses=4]
%tmp20 = bitcast <4 x float> %1 to <4 x i32> ; <<4 x i32>> [#uses=1]
%tmp22 = and <4 x i32> %tmp20, <i32 2147483647, i32 2147483647, i32 2147483647, i32 2147483647> ; <<4 x i32>> [#uses=1]
%tmp23 = bitcast <4 x i32> %tmp22 to <4 x float> ; <<4 x float>> [#uses=1]
%tmp25 = bitcast <4 x float> %1 to <4 x i32> ; <<4 x i32>> [#uses=1]
%tmp27 = and <4 x i32> %tmp25, <i32 -2147483648, i32 -2147483648, i32 -2147483648, i32 -2147483648> ; <<4 x i32>> [#uses=2]
%tmp30 = call <4 x float> @llvm.x86.sse.cmp.ps(<4 x float> %tmp23, <4 x float> <float 8.388608e+06, float 8.388608e+06, float 8.388608e+06, float 8.388608e+06>, i8 5) ; <<4 x float>> [#uses=1]
%tmp34 = bitcast <4 x float> %tmp30 to <4 x i32> ; <<4 x i32>> [#uses=1]
%tmp36 = xor <4 x i32> %tmp34, <i32 -1, i32 -1, i32 -1, i32 -1> ; <<4 x i32>> [#uses=1]
%tmp37 = and <4 x i32> %tmp36, <i32 1258291200, i32 1258291200, i32 1258291200, i32 1258291200> ; <<4 x i32>> [#uses=1]
%tmp42 = or <4 x i32> %tmp37, %tmp27 ; <<4 x i32>> [#uses=1]
%tmp43 = bitcast <4 x i32> %tmp42 to <4 x float> ; <<4 x float>> [#uses=2]
%tmp45 = fadd <4 x float> %1, %tmp43 ; <<4 x float>> [#uses=1]
%tmp47 = fsub <4 x float> %tmp45, %tmp43 ; <<4 x float>> [#uses=2]
%tmp49 = call <4 x float> @llvm.x86.sse.cmp.ps(<4 x float> %1, <4 x float> %tmp47, i8 1) ; <<4 x float>> [#uses=1]
%2 = bitcast <4 x float> %tmp49 to <4 x i32> ; <<4 x i32>> [#uses=1]
%3 = call <4 x float> @llvm.x86.sse2.cvtdq2ps(<4 x i32> %2) nounwind readnone ; <<4 x float>> [#uses=1]
%tmp53 = fadd <4 x float> %tmp47, %3 ; <<4 x float>> [#uses=1]
%tmp55 = bitcast <4 x float> %tmp53 to <4 x i32> ; <<4 x i32>> [#uses=1]
%tmp57 = or <4 x i32> %tmp55, %tmp27 ; <<4 x i32>> [#uses=1]
%tmp58 = bitcast <4 x i32> %tmp57 to <4 x float> ; <<4 x float>> [#uses=1]
%4 = bitcast float* %y_addr.0 to <4 x float>* ; <<4 x float>*> [#uses=1]
store <4 x float> %tmp58, <4 x float>* %4, align 16
%5 = getelementptr float* %x_addr.0, i64 4 ; <float*> [#uses=1]
%6 = getelementptr float* %y_addr.0, i64 4 ; <float*> [#uses=1]
%7 = add i32 %i.0, 4 ; <i32> [#uses=1]
%8 = load i32* %n, align 4 ; <i32> [#uses=1]
%9 = icmp sgt i32 %8, %7 ; <i1> [#uses=1]
br i1 %9, label %bb60, label %return
bb60: ; preds = %bb, %entry
%x_addr.0 = phi float* [ %x, %entry ], [ %5, %bb ] ; <float*> [#uses=2]
%y_addr.0 = phi float* [ %y, %entry ], [ %6, %bb ] ; <float*> [#uses=2]
br label %bb
return: ; preds = %bb60
ret void
}
declare <4 x float> @llvm.x86.sse.cmp.ps(<4 x float>, <4 x float>, i8) nounwind readnone
declare <4 x float> @llvm.x86.sse2.cvtdq2ps(<4 x i32>) nounwind readnone
; CodeGen should use the correct register class when extracting
; a load from a zero-extending load for hoisting.
; CHECK-LABEL: default_get_pch_validity:
; CHECK: movl cl_options_count(%rip), %ecx
@cl_options_count = external constant i32 ; <i32*> [#uses=2]
define void @default_get_pch_validity() nounwind {
entry:
%tmp4 = load i32* @cl_options_count, align 4 ; <i32> [#uses=1]
%tmp5 = icmp eq i32 %tmp4, 0 ; <i1> [#uses=1]
br i1 %tmp5, label %bb6, label %bb2
bb2: ; preds = %bb2, %entry
%i.019 = phi i64 [ 0, %entry ], [ %tmp25, %bb2 ] ; <i64> [#uses=1]
%tmp25 = add i64 %i.019, 1 ; <i64> [#uses=2]
%tmp11 = load i32* @cl_options_count, align 4 ; <i32> [#uses=1]
%tmp12 = zext i32 %tmp11 to i64 ; <i64> [#uses=1]
%tmp13 = icmp ugt i64 %tmp12, %tmp25 ; <i1> [#uses=1]
br i1 %tmp13, label %bb2, label %bb6
bb6: ; preds = %bb2, %entry
ret void
}