[SystemZ] Use LA instead of AGR in eliminateFrameIndex(). (llvm#80)

Since AGR clobbers CC it should not be used here.

Fixes https://bugs.llvm.org/show_bug.cgi?id=47736.

Review: Ulrich Weigand
Differential Revision: https://reviews.llvm.org/D89034

(cherry picked from commit d851495)

Co-authored-by: Jonas Paulsson <paulsson@linux.vnet.ibm.com>

Author: cuviper

llvm/lib/Target/SystemZ/SystemZRegisterInfo.cpp

@@ -321,8 +321,8 @@ SystemZRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
         // Load the high offset into the scratch register and use it as
         // an index.
         TII->loadImmediate(MBB, MI, ScratchReg, HighOffset);
-        BuildMI(MBB, MI, DL, TII->get(SystemZ::AGR),ScratchReg)
-          .addReg(ScratchReg, RegState::Kill).addReg(BasePtr);
+        BuildMI(MBB, MI, DL, TII->get(SystemZ::LA), ScratchReg)
+          .addReg(BasePtr, RegState::Kill).addImm(0).addReg(ScratchReg);
       }
 
       // Use the scratch register as the base.  It then dies here.

llvm/test/CodeGen/SystemZ/frame-14.ll

@@ -85,13 +85,13 @@ define void @f3() {
 define void @f4() {
 ; CHECK-NOFP-LABEL: f4:
 ; CHECK-NOFP: llilh %r1, 8
-; CHECK-NOFP: agr %r1, %r15
+; CHECK-NOFP: la %r1, 0(%r1,%r15)
 ; CHECK-NOFP: mvi 0(%r1), 42
 ; CHECK-NOFP: br %r14
 ;
 ; CHECK-FP-LABEL: f4:
 ; CHECK-FP: llilh %r1, 8
-; CHECK-FP: agr %r1, %r11
+; CHECK-FP: la %r1, 0(%r1,%r11)
 ; CHECK-FP: mvi 0(%r1), 42
 ; CHECK-FP: br %r14
   %region1 = alloca [524104 x i8], align 8
@@ -108,13 +108,13 @@ define void @f4() {
 define void @f5() {
 ; CHECK-NOFP-LABEL: f5:
 ; CHECK-NOFP: llilh %r1, 8
-; CHECK-NOFP: agr %r1, %r15
+; CHECK-NOFP: la %r1, 0(%r1,%r15)
 ; CHECK-NOFP: mvi 4095(%r1), 42
 ; CHECK-NOFP: br %r14
 ;
 ; CHECK-FP-LABEL: f5:
 ; CHECK-FP: llilh %r1, 8
-; CHECK-FP: agr %r1, %r11
+; CHECK-FP: la %r1, 0(%r1,%r11)
 ; CHECK-FP: mvi 4095(%r1), 42
 ; CHECK-FP: br %r14
   %region1 = alloca [524104 x i8], align 8
@@ -130,13 +130,13 @@ define void @f5() {
 define void @f6() {
 ; CHECK-NOFP-LABEL: f6:
 ; CHECK-NOFP: llilh %r1, 8
-; CHECK-NOFP: agr %r1, %r15
+; CHECK-NOFP: la %r1, 0(%r1,%r15)
 ; CHECK-NOFP: mviy 4096(%r1), 42
 ; CHECK-NOFP: br %r14
 ;
 ; CHECK-FP-LABEL: f6:
 ; CHECK-FP: llilh %r1, 8
-; CHECK-FP: agr %r1, %r11
+; CHECK-FP: la %r1, 0(%r1,%r11)
 ; CHECK-FP: mviy 4096(%r1), 42
 ; CHECK-FP: br %r14
   %region1 = alloca [524104 x i8], align 8
@@ -155,13 +155,13 @@ define void @f6() {
 define void @f7() {
 ; CHECK-NOFP-LABEL: f7:
 ; CHECK-NOFP: llilh %r1, 23
-; CHECK-NOFP: agr %r1, %r15
+; CHECK-NOFP: la %r1, 0(%r1,%r15)
 ; CHECK-NOFP: mviy 65535(%r1), 42
 ; CHECK-NOFP: br %r14
 ;
 ; CHECK-FP-LABEL: f7:
 ; CHECK-FP: llilh %r1, 23
-; CHECK-FP: agr %r1, %r11
+; CHECK-FP: la %r1, 0(%r1,%r11)
 ; CHECK-FP: mviy 65535(%r1), 42
 ; CHECK-FP: br %r14
   %region1 = alloca [1048400 x i8], align 8
@@ -178,13 +178,13 @@ define void @f7() {
 define void @f8() {
 ; CHECK-NOFP-LABEL: f8:
 ; CHECK-NOFP: llilh %r1, 24
-; CHECK-NOFP: agr %r1, %r15
+; CHECK-NOFP: la %r1, 0(%r1,%r15)
 ; CHECK-NOFP: mvi 7(%r1), 42
 ; CHECK-NOFP: br %r14
 ;
 ; CHECK-FP-LABEL: f8:
 ; CHECK-FP: llilh %r1, 24
-; CHECK-FP: agr %r1, %r11
+; CHECK-FP: la %r1, 0(%r1,%r11)
 ; CHECK-FP: mvi 7(%r1), 42
 ; CHECK-FP: br %r14
   %region1 = alloca [1048408 x i8], align 8
@@ -233,15 +233,15 @@ define void @f10(i32 *%vptr) {
 ; CHECK-NOFP-LABEL: f10:
 ; CHECK-NOFP: stg [[REGISTER:%r[1-9][0-4]?]], [[OFFSET:160|168]](%r15)
 ; CHECK-NOFP: llilh [[REGISTER]], 8
-; CHECK-NOFP: agr [[REGISTER]], %r15
+; CHECK-NOFP: la [[REGISTER]], 0([[REGISTER]],%r15)
 ; CHECK-NOFP: mvi 0([[REGISTER]]), 42
 ; CHECK-NOFP: lg [[REGISTER]], [[OFFSET]](%r15)
 ; CHECK-NOFP: br %r14
 ;
 ; CHECK-FP-LABEL: f10:
 ; CHECK-FP: stg [[REGISTER:%r[1-9][0-4]?]], [[OFFSET:160|168]](%r11)
 ; CHECK-FP: llilh [[REGISTER]], 8
-; CHECK-FP: agr [[REGISTER]], %r11
+; CHECK-FP: la [[REGISTER]], 0([[REGISTER]],%r11)
 ; CHECK-FP: mvi 0([[REGISTER]]), 42
 ; CHECK-FP: lg [[REGISTER]], [[OFFSET]](%r11)
 ; CHECK-FP: br %r14
@@ -273,7 +273,7 @@ define void @f11(i32 *%vptr) {
 ; CHECK-NOFP: stmg %r6, %r15,
 ; CHECK-NOFP: stg [[REGISTER:%r[1-9][0-4]?]], [[OFFSET:160|168]](%r15)
 ; CHECK-NOFP: llilh [[REGISTER]], 8
-; CHECK-NOFP: agr [[REGISTER]], %r15
+; CHECK-NOFP: la [[REGISTER]], 0([[REGISTER]],%r15)
 ; CHECK-NOFP: mvi 0([[REGISTER]]), 42
 ; CHECK-NOFP: lg [[REGISTER]], [[OFFSET]](%r15)
 ; CHECK-NOFP: lmg %r6, %r15,

llvm/test/CodeGen/SystemZ/frame-16.ll

@@ -311,13 +311,13 @@ define void @f11(i32 *%vptr, i8 %byte) {
 define void @f12(i8 %byte, i64 %index) {
 ; CHECK-NOFP-LABEL: f12:
 ; CHECK-NOFP: llilh %r1, 8
-; CHECK-NOFP: agr %r1, %r15
+; CHECK-NOFP: la %r1, 0(%r1,%r15)
 ; CHECK-NOFP: stc %r2, 0(%r3,%r1)
 ; CHECK-NOFP: br %r14
 ;
 ; CHECK-FP-LABEL: f12:
 ; CHECK-FP: llilh %r1, 8
-; CHECK-FP: agr %r1, %r11
+; CHECK-FP: la %r1, 0(%r1,%r11)
 ; CHECK-FP: stc %r2, 0(%r3,%r1)
 ; CHECK-FP: br %r14
   %region1 = alloca [524104 x i8], align 8