[ARM] do not consider sp as deprecated for ldm/stm

Early versions of the ARMv7 reference manuals considered the sp register as a deprecated register for ldm/stm familiy of instructions. However, later versions such as ARM DDI 0406C.d added a note to the Appendix: D9.3 Use of the SP as a general-purpose register Most ARM instructions, unlike Thumb instructions, provide exactly the same access to the SP as to R0-R12. This means that it is possible to use the SP as a general-purpose register. Earlier issues of this manual deprecated the use of SP in an ARM instruction, in any way that is deprecated, not permitted, or not possible in the corresponding Thumb instruction. However, user feedback indicates a number of cases where these instructions are useful. Therefore, ARM no longer deprecates these instruction uses. Also Armv8 manuals no longer consider SP as deprecated register for ldm/ stm A32 instructions. Furthermore, GNU as also does not print a deprecated warning when using SP with those instructions. Drop deprecation warning for pop/ldm/push/stm instructions. Patch by: Stefan Agner. Differential Revision: https://reviews.llvm.org/D82692
llvm · Feb 23, 2021 · e1c3bf6 · e1c3bf6
1 parent dd2dbf7
commit e1c3bf6
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diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp
@@ -107,9 +107,8 @@ static bool getARMStoreDeprecationInfo(MCInst &MI, const MCSubtargetInfo &STI,
   assert(MI.getNumOperands() >= 4 && "expected >= 4 arguments");
   for (unsigned OI = 4, OE = MI.getNumOperands(); OI < OE; ++OI) {
     assert(MI.getOperand(OI).isReg() && "expected register");
-    if (MI.getOperand(OI).getReg() == ARM::SP ||
-        MI.getOperand(OI).getReg() == ARM::PC) {
-      Info = "use of SP or PC in the list is deprecated";
+    if (MI.getOperand(OI).getReg() == ARM::PC) {
+      Info = "use of PC in the list is deprecated";
       return true;
     }
   }
@@ -134,9 +133,6 @@ static bool getARMLoadDeprecationInfo(MCInst &MI, const MCSubtargetInfo &STI,
     case ARM::PC:
       ListContainsPC = true;
       break;
-    case ARM::SP:
-      Info = "use of SP in the list is deprecated";
-      return true;
     }
   }
 

diff --git a/llvm/test/CodeGen/ARM/deprecated-asm.s b/llvm/test/CodeGen/ARM/deprecated-asm.s
@@ -1,6 +1,6 @@
 // REQUIRES: asserts
 // RUN: llvm-mc < %s  -triple=armv4t-linux-gnueabi -filetype=obj -o %t.o -no-deprecated-warn -stats 2>&1 | FileCheck %s
-// RUN: llvm-mc < %s  -triple=armv4t-linux-gnueabi -filetype=obj -o %t.o 2>&1 | FileCheck %s -check-prefix=WARN
+// RUN: llvm-mc < %s  -triple=armv4t-linux-gnueabi -filetype=obj -o %t.o -stats 2>&1 | FileCheck %s
 
 	.text
 	.syntax unified

diff --git a/llvm/test/MC/ARM/arm-load-store-multiple-deprecated.s b/llvm/test/MC/ARM/arm-load-store-multiple-deprecated.s
@@ -4,6 +4,9 @@
 @ RUN:   | FileCheck -check-prefix CHECK-ERROR %s
 
 @ RUN: not llvm-mc -triple armv7-linux-eabi -filetype asm -o - %s 2>&1 \
+@ RUN:   | FileCheck %s -check-prefix CHECK -check-prefix CHECK-V7
+
+@ RUN: not llvm-mc -triple armv8-linux-eabi -filetype asm -o - %s 2>&1 \
 @ RUN:   | FileCheck %s -check-prefix CHECK -check-prefix CHECK-V7
 
 	.syntax unified
@@ -13,152 +16,107 @@
 	.type stm,%function
 stm:
 	stm sp!, {r0, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK-ERROR: error: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
+@ CHECK-ERROR: error: use of PC in the list is deprecated
 @ CHECK: stm sp!, {r0, pc}
-@ CHECK: ^
-	stm r0!, {r0, sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK-ERROR: error: use of SP or PC in the list is deprecated
-@ CHECK: stm r0!, {r0, sp}
 @ CHECK: ^
 	stm r1!, {r0, sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stm r1!, {r0, sp, pc}
 @ CHECK: ^
 	stm r2!, {sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stm r2!, {sp, pc}
 @ CHECK: ^
 	stm sp!, {pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stm sp!, {pc}
-@ CHECK: ^
-	stm r0!, {sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK: stm r0!, {sp}
 @ CHECK: ^
 
 	.global stmda
 	.type stmda,%function
 stmda:
 	stmda sp!, {r0, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmda sp!, {r0, pc}
-@ CHECK: ^
-	stmda r0!, {r0, sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK: stmda r0!, {r0, sp}
 @ CHECK: ^
 	stmda r1!, {r0, sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmda r1!, {r0, sp, pc}
 @ CHECK: ^
 	stmda r2!, {sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmda r2!, {sp, pc}
 @ CHECK: ^
 	stmda sp!, {pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmda sp!, {pc}
-@ CHECK: ^
-	stmda r0!, {sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK: stmda r0!, {sp}
 @ CHECK: ^
 
 	.global stmdb
 	.type stmdb,%function
 stmdb:
 	stmdb sp!, {r0, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmdb sp!, {r0, pc}
-@ CHECK: ^
-	stmdb r0!, {r0, sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK: stmdb r0!, {r0, sp}
 @ CHECK: ^
 	stmdb r1!, {r0, sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmdb r1!, {r0, sp, pc}
 @ CHECK: ^
 	stmdb r2!, {sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmdb r2!, {sp, pc}
 @ CHECK: ^
 	stmdb sp!, {pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmdb sp!, {pc}
-@ CHECK: ^
-	stmdb r0!, {sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK: stmdb r0!, {sp}
 @ CHECK: ^
 
 	.global stmib
 	.type stmib,%function
 stmib:
 	stmib sp!, {r0, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmib sp!, {r0, pc}
-@ CHECK: ^
-	stmib r0!, {r0, sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK: stmib r0!, {r0, sp}
 @ CHECK: ^
 	stmib r1!, {r0, sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmib r1!, {r0, sp, pc}
 @ CHECK: ^
 	stmib r2!, {sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmib r2!, {sp, pc}
 @ CHECK: ^
 	stmib sp!, {pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: stmib sp!, {pc}
-@ CHECK: ^
-	stmib r0!, {sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK: stmib r0!, {sp}
 @ CHECK: ^
 
 
 	.global push
 	.type push,%function
 push:
 	push {r0, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: push {r0, pc}
-@ CHECK: ^
-	push {r0, sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK: push {r0, sp}
 @ CHECK: ^
 	push {r0, sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: push {r0, sp, pc}
 @ CHECK: ^
 	push {sp, pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: push {sp, pc}
 @ CHECK: ^
 	push {pc}
-@ CHECK: warning: use of SP or PC in the list is deprecated
+@ CHECK: warning: use of PC in the list is deprecated
 @ CHECK: push {pc}
-@ CHECK: ^
-	push {sp}
-@ CHECK: warning: use of SP or PC in the list is deprecated
-@ CHECK: push {sp}
 @ CHECK: ^
 
 	.global ldm
 	.type ldm,%function
 ldm:
-	ldm r0!, {r1, sp}
-@ CHECK: warning: use of SP in the list is deprecated
-	ldm r0!, {sp}
-@ CHECK: warning: use of SP in the list is deprecated
 	ldm r0!, {r1, lr, pc}
 @ CHECK: warning: use of LR and PC simultaneously in the list is deprecated
 	ldm r0!, {lr, pc}
@@ -167,10 +125,6 @@ ldm:
 	.global ldmda
 	.type ldmda,%function
 ldmda:
-	ldmda r0!, {r1, sp}
-@ CHECK: warning: use of SP in the list is deprecated
-	ldmda r0!, {sp}
-@ CHECK: warning: use of SP in the list is deprecated
 	ldmda r0!, {r1, lr, pc}
 @ CHECK: warning: use of LR and PC simultaneously in the list is deprecated
 	ldmda r0!, {lr, pc}
@@ -179,10 +133,6 @@ ldmda:
 	.global ldmdb
 	.type ldmdb,%function
 ldmdb:
-	ldmdb r0!, {r1, sp}
-@ CHECK: warning: use of SP in the list is deprecated
-	ldmdb r0!, {sp}
-@ CHECK: warning: use of SP in the list is deprecated
 	ldmdb r0!, {r1, lr, pc}
 @ CHECK: warning: use of LR and PC simultaneously in the list is deprecated
 	ldmdb r0!, {lr, pc}
@@ -191,10 +141,6 @@ ldmdb:
 	.global ldmib
 	.type ldmib,%function
 ldmib:
-	ldmib r0!, {r1, sp}
-@ CHECK: warning: use of SP in the list is deprecated
-	ldmib r0!, {sp}
-@ CHECK: warning: use of SP in the list is deprecated
 	ldmib r0!, {r1, lr, pc}
 @ CHECK: warning: use of LR and PC simultaneously in the list is deprecated
 	ldmib r0!, {lr, pc}
@@ -204,23 +150,69 @@ ldmib:
 	.type pop,%function
 pop:
 	pop {r0, sp}
-@ CHECK: warning: use of SP in the list is deprecated
 @ CHECK-V7: error: writeback register not allowed in register list
 	pop {sp}
-@ CHECK: warning: use of SP in the list is deprecated
 @ CHECK-V7: error: writeback register not allowed in register list
 	pop {r0, lr, pc}
 @ CHECK: warning: use of LR and PC simultaneously in the list is deprecated
 	pop {lr, pc}
 @ CHECK: warning: use of LR and PC simultaneously in the list is deprecated
 
-	.global valid
+	.global valid_stm
 	.type valid,%function
-valid:
+valid_stm:
+	stm r0!, {r0, sp}
+@ CHECK: stm r0!, {r0, sp}
+	stm r0!, {sp}
+@ CHECK: stm r0!, {sp}
+	stmda r0!, {r0, sp}
+@ CHECK: stmda r0!, {r0, sp}
+	stmda r0!, {sp}
+@ CHECK: stmda r0!, {sp}
+	stmdb r0!, {r0, sp}
+@ CHECK: stmdb r0!, {r0, sp}
+	stmdb r0!, {sp}
+@ CHECK: stmdb r0!, {sp}
+	stmib r0!, {r0, sp}
+@ CHECK: stmib r0!, {r0, sp}
+	stmib r0!, {sp}
+@ CHECK: stmib r0!, {sp}
 	stmdaeq r0, {r0}
 @ CHECK: stmdaeq r0, {r0}
+
+	.global valid_push
+	.type valid,%function
+valid_push:
+	push {r0, sp}
+@ CHECK: push {r0, sp}
+	push {sp}
+@ CHECK: push {sp}
+
+	.global valid_ldm
+	.type valid,%function
+valid_ldm:
+	ldm r0!, {r1, sp}
+@ CHECK: ldm r0!, {r1, sp}
+	ldm r0!, {sp}
+@ CHECK: ldm r0!, {sp}
+	ldmda r0!, {r1, sp}
+@ CHECK: ldmda r0!, {r1, sp}
+	ldmda r0!, {sp}
+@ CHECK: ldmda r0!, {sp}
+	ldmdb r0!, {r1, sp}
+@ CHECK: ldmdb r0!, {r1, sp}
+	ldmdb r0!, {sp}
+@ CHECK: ldmdb r0!, {sp}
+	ldmib r0!, {r1, sp}
+@ CHECK: ldmib r0!, {r1, sp}
+	ldmib r0!, {sp}
+@ CHECK: ldmib r0!, {sp}
 	ldmdaeq r0, {r0}
 @ CHECK: ldmdaeq r0, {r0}
+
+	.global valid_pop
+	.type valid,%function
+valid_pop:
 	pop {r0, pc}
 @ CHECK: pop {r0, pc}