Fix for PR 26356

Using the load immediate only when the immediate (whether signed or unsigned)
can fit in a 16-bit signed field. Namely, from -32768 to 32767 for signed and
0 to 65535 for unsigned. This patch also ensures that we sign-extend under the
right conditions.

llvm-svn: 259840

1 files changed, 136 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/PowerPC/pr26356.ll b/llvm/test/CodeGen/PowerPC/pr26356.ll
new file mode 100644
index 00000000000..0f5d877b576
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/pr26356.ll
@@ -0,0 +1,136 @@
+; RUN: llc -O0 -mcpu=pwr7 -mtriple=powerpc64le-unknown-unknown < %s | FileCheck %s
+
+define zeroext i32 @f1() {
+entry:
+  ret i32 65535
+}
+; CHECK-LABEL: @f1
+; CHECK: lis 3, 0
+; CHECK: ori 3, 3, 65535
+
+define zeroext i32 @f2() {
+entry:
+  ret i32 32768
+}
+; CHECK-LABEL: @f2
+; CHECK: lis 3, 0
+; CHECK: ori 3, 3, 32768
+
+define zeroext i32 @f3() {
+entry:
+  ret i32 32767
+}
+; CHECK-LABEL: @f3
+; CHECK: li 3, 32767
+
+define zeroext i16 @f4() {
+entry:
+  ret i16 65535
+}
+; CHECK-LABEL: @f4
+; CHECK: lis 3, 0
+; CHECK: ori 3, 3, 65535
+
+define zeroext i16 @f5() {
+entry:
+  ret i16 32768
+}
+; CHECK-LABEL: @f5
+; CHECK: lis 3, 0
+; CHECK: ori 3, 3, 32768
+
+define zeroext i16 @f6() {
+entry:
+  ret i16 32767
+}
+; CHECK-LABEL: @f6
+; CHECK: li 3, 32767
+
+define zeroext i16 @f7() {
+entry:
+  ret i16 -1
+}
+; CHECK-LABEL: @f7
+; CHECK: lis 3, 0
+; CHECK: ori 3, 3, 65535
+
+define zeroext i16 @f8() {
+entry:
+  ret i16 -32768
+}
+; CHECK-LABEL: @f8
+; CHECK: lis 3, 0
+; CHECK: ori 3, 3, 32768
+
+define signext i32 @f1s() {
+entry:
+  ret i32 65535
+}
+; CHECK-LABEL: @f1s
+; CHECK: lis 3, 0
+; CHECK: ori 3, 3, 65535
+
+define signext i32 @f2s() {
+entry:
+  ret i32 32768
+}
+; CHECK-LABEL: @f2s
+; CHECK: lis 3, 0
+; CHECK: ori 3, 3, 32768
+
+define signext i32 @f3s() {
+entry:
+  ret i32 32767
+}
+; CHECK-LABEL: @f3s
+; CHECK: li 3, 32767
+
+define signext i16 @f4s() {
+entry:
+  ret i16 32767
+}
+; CHECK-LABEL: @f4s
+; CHECK: li 3, 32767
+
+define signext i32 @f1sn() {
+entry:
+  ret i32 -65535
+}
+; CHECK-LABEL: @f1sn
+; CHECK: lis 3, -1
+; CHECK: ori 3, 3, 1
+
+define signext i32 @f2sn() {
+entry:
+  ret i32 -32768
+}
+; CHECK-LABEL: @f2sn
+; CHECK: li 3, -32768
+
+define signext i32 @f3sn() {
+entry:
+  ret i32 -32767
+}
+; CHECK-LABEL: @f3sn
+; CHECK: li 3, -32767
+
+define signext i32 @f4sn() {
+entry:
+  ret i32 -65536
+}
+; CHECK-LABEL: @f4sn
+; CHECK: lis 3, -1
+
+define signext i16 @f5sn() {
+entry:
+  ret i16 -32767
+}
+; CHECK-LABEL: @f5sn
+; CHECK: li 3, -32767
+
+define signext i16 @f6sn() {
+entry:
+  ret i16 -32768
+}
+; CHECK-LABEL: @f6sn
+; CHECK: li 3, -32768