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|
# RUN: llc -mcpu=haswell -filetype=obj -start-before stack-protector -O2 %s -o - | llvm-objdump -d - | FileCheck %s
# Test 1:
#
# Source C code:
# volatile int y;
# volatile int x;
#
# int switchCase(int z, int w) {
# int result = 0;
# while (x > 0 && y < 0) {
# switch(z) {
# case 0:
# result+=result*5;break;
# case 1:
# result--; break;
# case 2:
# result *= result; break;
# case 3:
# result <<= 7; break;
# case 4:
# result >>= 7; break;
# case 5:
# result = result * 16 | ~result; break;
# }
# }
# return result;
# }
#
# CHECK: 49: eb 4a jmp 74 <switchCase+0x95>
# CHECK: 57: eb 3c jmp 60 <switchCase+0x95>
# CHECK: 65: eb 2e jmp 46 <switchCase+0x95>
# CHECK: 73: eb 20 jmp 32 <switchCase+0x95>
# CHECK: 81: eb 12 jmp 18 <switchCase+0x95>
# CHECK: 93: 7f 8b jg -117 <switchCase+0x20>
# Test 2:
#
# Source C code:
#
# int ifElse(int z) {
# int w = 0;
# while(1) {
# if(x < 0)
# w++;
# else if(y > 0)
# w--;
# else if((x & y) == 3)
# w*=2;
# else if ((x | y) == 18)
# w += 2;
# else if ((y ^ x) == 154)
# w -= 3;
# else if(((y ^ x) & 1) != 0)
# break;
# }
# return w;
# }
#
# CHECK: 129: eb 13 jmp 19 <ifElse+0x7e>
# CHECK: 12e: eb a0 jmp -96 <ifElse+0x10>
# CHECK: 132: eb 9c jmp -100 <ifElse+0x10>
# CHECK: 137: eb 97 jmp -105 <ifElse+0x10>
# CHECK: 13c: eb 92 jmp -110 <ifElse+0x10>
--- |
; ModuleID = 'D:\iusers\opaparo\dev_test\branch_instruction_and_target_split_perf_nops.ll'
source_filename = "D:\5C\5Ciusers\5C\5Copaparo\5C\5Cdev_test\5C\5Cbranch_instruction_and_target_split_perf_nops.c"
target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-windows-msvc19.0.24210"
@x = common global i32 0, align 4
@y = common global i32 0, align 4
; Function Attrs: norecurse nounwind uwtable
define i32 @switchCase(i32 %z, i32 %w) local_unnamed_addr #0 {
entry:
%0 = load volatile i32, i32* @x, align 4, !tbaa !3
%cmp19 = icmp sgt i32 %0, 0
br i1 %cmp19, label %land.rhs.preheader, label %while.end
land.rhs.preheader: ; preds = %entry
br label %land.rhs
land.rhs: ; preds = %sw.epilog, %land.rhs.preheader
%result.020 = phi i32 [ %result.1, %sw.epilog ], [ 0, %land.rhs.preheader ]
%1 = load volatile i32, i32* @y, align 4, !tbaa !3
%cmp1 = icmp slt i32 %1, 0
br i1 %cmp1, label %while.body, label %while.end
while.body: ; preds = %land.rhs
switch i32 %z, label %sw.epilog [
i32 0, label %sw.bb
i32 1, label %sw.bb2
i32 2, label %sw.bb3
i32 3, label %sw.bb5
i32 4, label %sw.bb6
i32 5, label %sw.bb7
]
sw.bb: ; preds = %while.body
%add = mul nsw i32 %result.020, 6
br label %sw.epilog
sw.bb2: ; preds = %while.body
%dec = add nsw i32 %result.020, -1
br label %sw.epilog
sw.bb3: ; preds = %while.body
%mul4 = mul nsw i32 %result.020, %result.020
br label %sw.epilog
sw.bb5: ; preds = %while.body
%shl = shl i32 %result.020, 7
br label %sw.epilog
sw.bb6: ; preds = %while.body
%shr = ashr i32 %result.020, 7
br label %sw.epilog
sw.bb7: ; preds = %while.body
%mul8 = shl nsw i32 %result.020, 4
%neg = xor i32 %result.020, -1
%or = or i32 %mul8, %neg
br label %sw.epilog
sw.epilog: ; preds = %sw.bb7, %sw.bb6, %sw.bb5, %sw.bb3, %sw.bb2, %sw.bb, %while.body
%result.1 = phi i32 [ %result.020, %while.body ], [ %or, %sw.bb7 ], [ %shr, %sw.bb6 ], [ %shl, %sw.bb5 ], [ %mul4, %sw.bb3 ], [ %dec, %sw.bb2 ], [ %add, %sw.bb ]
%2 = load volatile i32, i32* @x, align 4, !tbaa !3
%cmp = icmp sgt i32 %2, 0
br i1 %cmp, label %land.rhs, label %while.end
while.end: ; preds = %sw.epilog, %land.rhs, %entry
%result.0.lcssa = phi i32 [ 0, %entry ], [ %result.020, %land.rhs ], [ %result.1, %sw.epilog ]
ret i32 %result.0.lcssa
}
; Function Attrs: norecurse nounwind uwtable
define i32 @ifElse(i32 %z) local_unnamed_addr #0 {
entry:
br label %while.cond.outer
while.cond.outer: ; preds = %if.then, %if.then2, %if.then5, %if.then8, %if.then11, %entry
%w.0.ph = phi i32 [ 0, %entry ], [ %sub, %if.then11 ], [ %add, %if.then8 ], [ %mul, %if.then5 ], [ %dec, %if.then2 ], [ %inc, %if.then ]
br label %while.cond
while.cond: ; preds = %if.else12, %while.cond.outer
%0 = load volatile i32, i32* @x, align 4, !tbaa !3
%cmp = icmp slt i32 %0, 0
br i1 %cmp, label %if.then, label %if.else
if.then: ; preds = %while.cond
%inc = add nsw i32 %w.0.ph, 1
br label %while.cond.outer
if.else: ; preds = %while.cond
%1 = load volatile i32, i32* @y, align 4, !tbaa !3
%cmp1 = icmp sgt i32 %1, 0
br i1 %cmp1, label %if.then2, label %if.else3
if.then2: ; preds = %if.else
%dec = add nsw i32 %w.0.ph, -1
br label %while.cond.outer
if.else3: ; preds = %if.else
%2 = load volatile i32, i32* @x, align 4, !tbaa !3
%3 = load volatile i32, i32* @y, align 4, !tbaa !3
%and = and i32 %3, %2
%cmp4 = icmp eq i32 %and, 3
br i1 %cmp4, label %if.then5, label %if.else6
if.then5: ; preds = %if.else3
%mul = shl nsw i32 %w.0.ph, 1
br label %while.cond.outer
if.else6: ; preds = %if.else3
%4 = load volatile i32, i32* @x, align 4, !tbaa !3
%5 = load volatile i32, i32* @y, align 4, !tbaa !3
%or = or i32 %5, %4
%cmp7 = icmp eq i32 %or, 18
br i1 %cmp7, label %if.then8, label %if.else9
if.then8: ; preds = %if.else6
%add = add nsw i32 %w.0.ph, 2
br label %while.cond.outer
if.else9: ; preds = %if.else6
%6 = load volatile i32, i32* @y, align 4, !tbaa !3
%7 = load volatile i32, i32* @x, align 4, !tbaa !3
%xor = xor i32 %7, %6
%cmp10 = icmp eq i32 %xor, 154
br i1 %cmp10, label %if.then11, label %if.else12
if.then11: ; preds = %if.else9
%sub = add nsw i32 %w.0.ph, -3
br label %while.cond.outer
if.else12: ; preds = %if.else9
%8 = load volatile i32, i32* @y, align 4, !tbaa !3
%9 = load volatile i32, i32* @x, align 4, !tbaa !3
%xor13 = xor i32 %9, %8
%and14 = and i32 %xor13, 1
%cmp15 = icmp eq i32 %and14, 0
br i1 %cmp15, label %while.cond, label %while.end
while.end: ; preds = %if.else12
ret i32 %w.0.ph
}
attributes #0 = { norecurse nounwind uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="haswell" "target-features"="+aes,+avx,+avx2,+bmi,+bmi2,+cx16,+f16c,+fma,+fsgsbase,+fxsr,+lzcnt,+mmx,+movbe,+pclmul,+popcnt,+rdrnd,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave,+xsaveopt" "unsafe-fp-math"="false" "use-soft-float"="false" }
!llvm.module.flags = !{!0, !1}
!llvm.ident = !{!2}
!0 = !{i32 1, !"wchar_size", i32 2}
!1 = !{i32 7, !"PIC Level", i32 2}
!2 = !{!"clang version 6.0.0 (ssh://git-amr-1.devtools.intel.com:29418/dpd_icl-llvm_clang_worldread 3789ad4283ec09df1ed8411abbb227d76e7ef8cb) (ssh://git-amr-1.devtools.intel.com:29418/dpd_icl-llvm_llvm_worldread 42897913cc9fac0d94e8636d9aed4dc193d7864e)"}
!3 = !{!4, !4, i64 0}
!4 = !{!"int", !5, i64 0}
!5 = !{!"omnipotent char", !6, i64 0}
!6 = !{!"Simple C/C++ TBAA"}
...
---
name: switchCase
alignment: 4
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
tracksRegLiveness: true
registers:
liveins:
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 0
offsetAdjustment: 0
maxAlignment: 0
adjustsStack: false
hasCalls: false
stackProtector: ''
maxCallFrameSize: 4294967295
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
savePoint: ''
restorePoint: ''
fixedStack:
stack:
constants:
body: |
...
---
name: ifElse
alignment: 4
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
tracksRegLiveness: true
registers:
liveins:
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 0
offsetAdjustment: 0
maxAlignment: 0
adjustsStack: false
hasCalls: false
stackProtector: ''
maxCallFrameSize: 4294967295
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
savePoint: ''
restorePoint: ''
fixedStack:
stack:
constants:
body: |
...
|
