MIsched: add an ILP window property to machine model.

This was an experimental option, but needs to be defined
per-target. e.g. PPC A2 needs to aggressively hide latency.

I converted some in-order scheduling tests to A2. Hal is working on
more test cases.

llvm-svn: 171946

1 files changed, 55 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/PowerPC/misched-inorder-latency.ll b/llvm/test/CodeGen/PowerPC/misched-inorder-latency.ll
new file mode 100644
index 00000000000..8fae7ad4d1d
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/misched-inorder-latency.ll
@@ -0,0 +1,55 @@
+; RUN: llc < %s -enable-misched -pre-RA-sched=source -scheditins=false \
+; RUN:          -disable-ifcvt-triangle-false -disable-post-ra | FileCheck %s
+;
+target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128-v128:128:128-n32:64"
+target triple = "powerpc64-bgq-linux"
+
+; %val1 is a load live out of %entry. It should be hoisted
+; above the add.
+; CHECK: testload:
+; CHECK: %entry
+; CHECK: lwz
+; CHECK: addi
+; CHECK: bne
+; CHECK: %true
+define i32 @testload(i32 *%ptr, i32 %sumin) {
+entry:
+  %sum1 = add i32 %sumin, 1
+  %val1 = load i32* %ptr
+  %p = icmp eq i32 %sumin, 0
+  br i1 %p, label %true, label %end
+true:
+  %sum2 = add i32 %sum1, 1
+  %ptr2 = getelementptr i32* %ptr, i32 1
+  %val = load i32* %ptr2
+  %val2 = add i32 %val1, %val
+  br label %end
+end:
+  %valmerge = phi i32 [ %val1, %entry], [ %val2, %true ]
+  %summerge = phi i32 [ %sum1, %entry], [ %sum2, %true ]
+  %sumout = add i32 %valmerge, %summerge
+  ret i32 %sumout
+}
+
+; The prefetch gets a default latency of 3 cycles and should be hoisted
+; above the add.
+;
+; CHECK: testprefetch:
+; CHECK: %entry
+; CHECK: dcbt
+; CHECK: addi
+; CHECK: blr
+define i32 @testprefetch(i8 *%ptr, i32 %i) {
+entry:
+  %val1 = add i32 %i, 1
+  tail call void @llvm.prefetch( i8* %ptr, i32 0, i32 3, i32 1 )
+  %p = icmp eq i32 %i, 0
+  br i1 %p, label %true, label %end
+true:
+  %val2 = add i32 %val1, 1
+  br label %end
+end:
+  %valmerge = phi i32 [ %val1, %entry], [ %val2, %true ]
+  ret i32 %valmerge
+}
+declare void @llvm.prefetch(i8*, i32, i32, i32) nounwind