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author | Richard Sandiford <rsandifo@linux.vnet.ibm.com> | 2013-07-03 10:10:02 +0000 |
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committer | Richard Sandiford <rsandifo@linux.vnet.ibm.com> | 2013-07-03 10:10:02 +0000 |
commit | fa487e83a83c260d6a50f3df00a0eb012553a912 (patch) | |
tree | f6ddd72df044eaa9cabbce37fd4b04f64b978139 /test/CodeGen/SystemZ/int-sub-05.ll | |
parent | b81b477cd4392a51112c3af0659ea9fc176e74f1 (diff) | |
download | llvm-fa487e83a83c260d6a50f3df00a0eb012553a912.tar.gz llvm-fa487e83a83c260d6a50f3df00a0eb012553a912.tar.bz2 llvm-fa487e83a83c260d6a50f3df00a0eb012553a912.tar.xz |
[SystemZ] Fold more spills
Add a mapping from register-based <INSN>R instructions to the corresponding
memory-based <INSN>. Use it to cut down on the number of spill loads.
Some instructions extend their operands from smaller fields, so this
required a new TSFlags field to say how big the unextended operand is.
This optimisation doesn't trigger for C(G)R and CL(G)R because in practice
we always combine those instructions with a branch. Adding a test for every
other case probably seems excessive, but it did catch a missed optimisation
for DSGF (fixed in r185435).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185529 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'test/CodeGen/SystemZ/int-sub-05.ll')
-rw-r--r-- | test/CodeGen/SystemZ/int-sub-05.ll | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/test/CodeGen/SystemZ/int-sub-05.ll b/test/CodeGen/SystemZ/int-sub-05.ll index 1475b244f6..5d95e79080 100644 --- a/test/CodeGen/SystemZ/int-sub-05.ll +++ b/test/CodeGen/SystemZ/int-sub-05.ll @@ -2,6 +2,8 @@ ; ; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s +declare i128 *@foo() + ; Test register addition. define void @f1(i128 *%ptr, i64 %high, i64 %low) { ; CHECK: f1: @@ -116,3 +118,35 @@ define void @f7(i64 %base) { store i128 %sub, i128 *%aptr ret void } + +; Check that subtractions of spilled values can use SLG and SLBG rather than +; SLGR and SLBGR. +define void @f8(i128 *%ptr0) { +; CHECK: f8: +; CHECK: brasl %r14, foo@PLT +; CHECK: slg {{%r[0-9]+}}, {{[0-9]+}}(%r15) +; CHECK: slbg {{%r[0-9]+}}, {{[0-9]+}}(%r15) +; CHECK: br %r14 + %ptr1 = getelementptr i128 *%ptr0, i128 2 + %ptr2 = getelementptr i128 *%ptr0, i128 4 + %ptr3 = getelementptr i128 *%ptr0, i128 6 + %ptr4 = getelementptr i128 *%ptr0, i128 8 + + %val0 = load i128 *%ptr0 + %val1 = load i128 *%ptr1 + %val2 = load i128 *%ptr2 + %val3 = load i128 *%ptr3 + %val4 = load i128 *%ptr4 + + %retptr = call i128 *@foo() + + %ret = load i128 *%retptr + %sub0 = sub i128 %ret, %val0 + %sub1 = sub i128 %sub0, %val1 + %sub2 = sub i128 %sub1, %val2 + %sub3 = sub i128 %sub2, %val3 + %sub4 = sub i128 %sub3, %val4 + store i128 %sub4, i128 *%retptr + + ret void +} |