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authorBenjamin Kramer <benny.kra@googlemail.com>2015-03-26 17:12:16 +0000
committerBenjamin Kramer <benny.kra@googlemail.com>2015-03-26 17:12:16 +0000
commit3d0031e0b8d3f2099e7d0278ef74e9d68a7fe15f (patch)
tree2c0bd91dc1f320ffbbf37e545fe352da8914d0c2 /llvm/lib
parent7fa8c430f748cc4b4dea08caa1a225b10a08563e (diff)
downloadbcm5719-llvm-3d0031e0b8d3f2099e7d0278ef74e9d68a7fe15f.tar.gz
bcm5719-llvm-3d0031e0b8d3f2099e7d0278ef74e9d68a7fe15f.zip
Remove outdated README-SSE.txt entries.
llvm-svn: 233292
Diffstat (limited to 'llvm/lib')
-rw-r--r--llvm/lib/Target/X86/README-SSE.txt78
1 files changed, 0 insertions, 78 deletions
diff --git a/llvm/lib/Target/X86/README-SSE.txt b/llvm/lib/Target/X86/README-SSE.txt
index 71329b06692..e6896e80556 100644
--- a/llvm/lib/Target/X86/README-SSE.txt
+++ b/llvm/lib/Target/X86/README-SSE.txt
@@ -93,36 +93,6 @@ The pattern isel got this one right.
//===---------------------------------------------------------------------===//
-SSE should implement 'select_cc' using 'emulated conditional moves' that use
-pcmp/pand/pandn/por to do a selection instead of a conditional branch:
-
-double %X(double %Y, double %Z, double %A, double %B) {
- %C = setlt double %A, %B
- %z = fadd double %Z, 0.0 ;; select operand is not a load
- %D = select bool %C, double %Y, double %z
- ret double %D
-}
-
-We currently emit:
-
-_X:
- subl $12, %esp
- xorpd %xmm0, %xmm0
- addsd 24(%esp), %xmm0
- movsd 32(%esp), %xmm1
- movsd 16(%esp), %xmm2
- ucomisd 40(%esp), %xmm1
- jb LBB_X_2
-LBB_X_1:
- movsd %xmm0, %xmm2
-LBB_X_2:
- movsd %xmm2, (%esp)
- fldl (%esp)
- addl $12, %esp
- ret
-
-//===---------------------------------------------------------------------===//
-
Lower memcpy / memset to a series of SSE 128 bit move instructions when it's
feasible.
@@ -787,25 +757,6 @@ cheaper to do fld1 than load from a constant pool for example, so
//===---------------------------------------------------------------------===//
-The X86 backend should be able to if-convert SSE comparisons like "ucomisd" to
-"cmpsd". For example, this code:
-
-double d1(double x) { return x == x ? x : x + x; }
-
-Compiles into:
-
-_d1:
- ucomisd %xmm0, %xmm0
- jnp LBB1_2
- addsd %xmm0, %xmm0
- ret
-LBB1_2:
- ret
-
-Also, the 'ret's should be shared. This is PR6032.
-
-//===---------------------------------------------------------------------===//
-
These should compile into the same code (PR6214): Perhaps instcombine should
canonicalize the former into the later?
@@ -858,35 +809,6 @@ doing a shuffle from v[1] to v[0] then a float store.
//===---------------------------------------------------------------------===//
-On SSE4 machines, we compile this code:
-
-define <2 x float> @test2(<2 x float> %Q, <2 x float> %R,
- <2 x float> *%P) nounwind {
- %Z = fadd <2 x float> %Q, %R
-
- store <2 x float> %Z, <2 x float> *%P
- ret <2 x float> %Z
-}
-
-into:
-
-_test2: ## @test2
-## BB#0:
- insertps $0, %xmm2, %xmm2
- insertps $16, %xmm3, %xmm2
- insertps $0, %xmm0, %xmm3
- insertps $16, %xmm1, %xmm3
- addps %xmm2, %xmm3
- movq %xmm3, (%rdi)
- movaps %xmm3, %xmm0
- pshufd $1, %xmm3, %xmm1
- ## kill: XMM1<def> XMM1<kill>
- ret
-
-The insertps's of $0 are pointless complex copies.
-
-//===---------------------------------------------------------------------===//
-
[UNSAFE FP]
void foo(double, double, double);
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