diff options
Diffstat (limited to 'lib/Target/README.txt')
| -rw-r--r-- | lib/Target/README.txt | 31 |
1 files changed, 18 insertions, 13 deletions
diff --git a/lib/Target/README.txt b/lib/Target/README.txt index 052a5756da9f..144bf5d3e3dc 100644 --- a/lib/Target/README.txt +++ b/lib/Target/README.txt @@ -263,19 +263,6 @@ if anyone cared enough about sincos. //===---------------------------------------------------------------------===// -Turn this into a single byte store with no load (the other 3 bytes are -unmodified): - -define void @test(i32* %P) { - %tmp = load i32* %P - %tmp14 = or i32 %tmp, 3305111552 - %tmp15 = and i32 %tmp14, 3321888767 - store i32 %tmp15, i32* %P - ret void -} - -//===---------------------------------------------------------------------===// - quantum_sigma_x in 462.libquantum contains the following loop: for(i=0; i<reg->size; i++) @@ -1843,3 +1830,21 @@ entry: //===---------------------------------------------------------------------===// +We should use DSE + llvm.lifetime.end to delete dead vtable pointer updates. +See GCC PR34949 + +//===---------------------------------------------------------------------===// + +In this code: + +long foo(long x) { + return x > 1 ? x : 1; +} + +LLVM emits a comparison with 1 instead of 0. 0 would be equivalent +and cheaper on most targets. + +LLVM prefers comparisons with zero over non-zero in general, but in this +case it choses instead to keep the max operation obvious. + +//===---------------------------------------------------------------------===// |