1 ; RUN: llc < %s -march=x86-64 -mcpu=bdver1 | FileCheck %s 2 3 ; clang -Oz -c test1.cpp -emit-llvm -S -o 4 ; Verify that we generate shld insruction when we are optimizing for size, 5 ; even for X86_64 processors that are known to have poor latency double 6 ; precision shift instructions. 7 ; uint64_t lshift10(uint64_t a, uint64_t b) 8 ; { 9 ; return (a << 10) | (b >> 54); 10 ; } 11 12 ; Function Attrs: minsize nounwind optsize readnone uwtable 13 define i64 @_Z8lshift10mm(i64 %a, i64 %b) #0 { 14 entry: 15 ; CHECK: shldq $10 16 %shl = shl i64 %a, 10 17 %shr = lshr i64 %b, 54 18 %or = or i64 %shr, %shl 19 ret i64 %or 20 } 21 22 attributes #0 = { minsize nounwind optsize readnone uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" } 23 24 25 ; clang -Os -c test2.cpp -emit-llvm -S 26 ; Verify that we generate shld insruction when we are optimizing for size, 27 ; even for X86_64 processors that are known to have poor latency double 28 ; precision shift instructions. 29 ; uint64_t lshift11(uint64_t a, uint64_t b) 30 ; { 31 ; return (a << 11) | (b >> 53); 32 ; } 33 34 ; Function Attrs: nounwind optsize readnone uwtable 35 define i64 @_Z8lshift11mm(i64 %a, i64 %b) #1 { 36 entry: 37 ; CHECK: shldq $11 38 %shl = shl i64 %a, 11 39 %shr = lshr i64 %b, 53 40 %or = or i64 %shr, %shl 41 ret i64 %or 42 } 43 44 attributes #1 = { nounwind optsize readnone uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" } 45 46 ; clang -O2 -c test2.cpp -emit-llvm -S 47 ; Verify that we do not generate shld insruction when we are not optimizing 48 ; for size for X86_64 processors that are known to have poor latency double 49 ; precision shift instructions. 50 ; uint64_t lshift12(uint64_t a, uint64_t b) 51 ; { 52 ; return (a << 12) | (b >> 52); 53 ; } 54 55 ; Function Attrs: nounwind optsize readnone uwtable 56 define i64 @_Z8lshift12mm(i64 %a, i64 %b) #2 { 57 entry: 58 ; CHECK: shlq $12 59 ; CHECK-NEXT: shrq $52 60 %shl = shl i64 %a, 12 61 %shr = lshr i64 %b, 52 62 %or = or i64 %shr, %shl 63 ret i64 %or 64 } 65 66 attributes #2= { nounwind readnone uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" } 67 68
