Changes in directory llvm/lib/Target/X86:
README-SSE.txt updated: 1.7 -> 1.8
README.txt updated: 1.143 -> 1.144
---
Log message:
These are done.
---
Diffs of the changes: (+0 -69)
README-SSE.txt | 58 ---------------------------------------------------------
README.txt | 11 ----------
2 files changed, 69 deletions(-)
Index: llvm/lib/Target/X86/README-SSE.txt
diff -u llvm/lib/Target/X86/README-SSE.txt:1.7
llvm/lib/Target/X86/README-SSE.txt:1.8
--- llvm/lib/Target/X86/README-SSE.txt:1.7 Wed Oct 18 12:04:09 2006
+++ llvm/lib/Target/X86/README-SSE.txt Fri Nov 10 16:03:35 2006
@@ -4,30 +4,6 @@
//===---------------------------------------------------------------------===//
-There are serious issues folding loads into "scalar sse" intrinsics. For
-example, this:
-
-float minss4( float x, float *y ) {
- return _mm_cvtss_f32(_mm_min_ss(_mm_set_ss(x),_mm_set_ss(*y)));
-}
-
-compiles to:
-
-_minss4:
- subl $4, %esp
- movl 12(%esp), %eax
-*** movss 8(%esp), %xmm0
-*** movss (%eax), %xmm1
-*** minss %xmm1, %xmm0
- movss %xmm0, (%esp)
- flds (%esp)
- addl $4, %esp
- ret
-
-Each operand of the minss is a load. At least one should be folded!
-
-//===---------------------------------------------------------------------===//
-
Expand libm rounding functions inline: Significant speedups possible.
http://gcc.gnu.org/ml/gcc-patches/2006-10/msg00909.html
@@ -165,17 +141,6 @@
//===---------------------------------------------------------------------===//
-Should generate min/max for stuff like:
-
-void minf(float a, float b, float *X) {
- *X = a <= b ? a : b;
-}
-
-Make use of floating point min / max instructions. Perhaps introduce ISD::FMIN
-and ISD::FMAX node types?
-
-//===---------------------------------------------------------------------===//
-
Lower memcpy / memset to a series of SSE 128 bit move instructions when it's
feasible.
@@ -225,29 +190,6 @@
//===---------------------------------------------------------------------===//
-Better codegen for:
-
-void f(float a, float b, vector float * out) { *out = (vector float){ a, 0.0,
0.0, b}; }
-void f(float a, float b, vector float * out) { *out = (vector float){ a, b,
0.0, 0}; }
-
-For the later we generate:
-
-_f:
- pxor %xmm0, %xmm0
- movss 8(%esp), %xmm1
- movaps %xmm0, %xmm2
- unpcklps %xmm1, %xmm2
- movss 4(%esp), %xmm1
- unpcklps %xmm0, %xmm1
- unpcklps %xmm2, %xmm1
- movl 12(%esp), %eax
- movaps %xmm1, (%eax)
- ret
-
-This seems like it should use shufps, one for each of a & b.
-
-//===---------------------------------------------------------------------===//
-
How to decide when to use the "floating point version" of logical ops? Here are
some code fragments:
Index: llvm/lib/Target/X86/README.txt
diff -u llvm/lib/Target/X86/README.txt:1.143
llvm/lib/Target/X86/README.txt:1.144
--- llvm/lib/Target/X86/README.txt:1.143 Sun Oct 22 16:40:12 2006
+++ llvm/lib/Target/X86/README.txt Fri Nov 10 16:03:35 2006
@@ -232,17 +232,6 @@
//===---------------------------------------------------------------------===//
-Should generate min/max for stuff like:
-
-void minf(float a, float b, float *X) {
- *X = a <= b ? a : b;
-}
-
-Make use of floating point min / max instructions. Perhaps introduce ISD::FMIN
-and ISD::FMAX node types?
-
-//===---------------------------------------------------------------------===//
-
The first BB of this code:
declare bool %foo()
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