Revert "builtins: Add ARM Thumb1 implementation for uidiv and uidivmod"

This reverts commit r288710.

r288710 breaks building the builtin libraries on Darwin for armv7em.

Build logs may still be avaialable here:
http://lab.llvm.org:8080/green/job/clang-stage2-configure-Rlto_build/12035/console

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@288773 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 22 insertions, 122 deletions

diff --git a/lib/builtins/arm/aeabi_uidivmod.S b/lib/builtins/arm/aeabi_uidivmod.S
index 7098bc6ff..4a8944908 100644
--- a/lib/builtins/arm/aeabi_uidivmod.S
+++ b/lib/builtins/arm/aeabi_uidivmod.S
@@ -23,20 +23,6 @@
         .syntax unified
         .p2align 2
 DEFINE_COMPILERRT_FUNCTION(__aeabi_uidivmod)
-#if __ARM_ARCH_ISA_THUMB == 1
-        cmp     r0, r1
-        bcc     LOCAL_LABEL(case_denom_larger)
-        push    {r0, r1, lr}
-        bl      SYMBOL_NAME(__aeabi_uidiv)
-        pop     {r1, r2, r3}
-        muls    r2, r2, r0 // r2 = quot * denom
-        subs    r1, r1, r2
-        JMP     (r3)
-LOCAL_LABEL(case_denom_larger):
-        movs    r1, r0
-        movs    r0, #0
-        JMP     (lr)
-#else
         push    { lr }
         sub     sp, sp, #4
         mov     r2, sp
@@ -49,7 +35,6 @@ LOCAL_LABEL(case_denom_larger):
         ldr     r1, [sp]
         add     sp, sp, #4
         pop     { pc }
-#endif
 END_COMPILERRT_FUNCTION(__aeabi_uidivmod)
 
 NO_EXEC_STACK_DIRECTIVE
diff --git a/lib/builtins/arm/udivsi3.S b/lib/builtins/arm/udivsi3.S
index 6739dc2ed..085f8fb9e 100644
--- a/lib/builtins/arm/udivsi3.S
+++ b/lib/builtins/arm/udivsi3.S
@@ -40,26 +40,12 @@ DEFINE_COMPILERRT_FUNCTION(__udivsi3)
 #else
 	cmp	r1, #1
 	bcc	LOCAL_LABEL(divby0)
-#if __ARM_ARCH_ISA_THUMB == 1
-	bne LOCAL_LABEL(num_neq_denom)
-	JMP(lr)
-LOCAL_LABEL(num_neq_denom):
-#else
 	IT(eq)
 	JMPc(lr, eq)
-#endif
 	cmp	r0, r1
-#if __ARM_ARCH_ISA_THUMB == 1
-	bhs LOCAL_LABEL(num_ge_denom)
-	movs r0, #0
-	JMP(lr)
-LOCAL_LABEL(num_ge_denom):
-#else
 	ITT(cc)
 	movcc	r0, #0
 	JMPc(lr, cc)
-#endif
-
 	/*
 	 * Implement division using binary long division algorithm.
 	 *
@@ -76,7 +62,7 @@ LOCAL_LABEL(num_ge_denom):
 	 * that (r0 << shift) < 2 * r1. The quotient is stored in r3.
 	 */
 
-#  if defined(__ARM_FEATURE_CLZ)
+#  ifdef __ARM_FEATURE_CLZ
 	clz	ip, r0
 	clz	r3, r1
 	/* r0 >= r1 implies clz(r0) <= clz(r1), so ip <= r3. */
@@ -91,128 +77,49 @@ LOCAL_LABEL(num_ge_denom):
 	sub	ip, ip, r3, lsl #3
 	mov	r3, #0
 	bx	ip
-#  else /* No CLZ Feature */
+#  else
 #    if __ARM_ARCH_ISA_THUMB == 2
 #    error THUMB mode requires CLZ or UDIV
 #    endif
-#    if __ARM_ARCH_ISA_THUMB == 1
-#      define BLOCK_SIZE 10
-#    else
-#      define BLOCK_SIZE 12
-#    endif
-
 	mov	r2, r0
-#    if __ARM_ARCH_ISA_THUMB == 1
-	mov ip, r0
-	adr r0, LOCAL_LABEL(div0block)
-	adds r0, #1
-#    else
 	adr	ip, LOCAL_LABEL(div0block)
-#    endif
-	lsrs	r3, r2, #16
+
+	lsr	r3, r2, #16
 	cmp	r3, r1
-#    if __ARM_ARCH_ISA_THUMB == 1
-	blo LOCAL_LABEL(skip_16)
-	movs r2, r3
-	subs r0, r0, #(16 * BLOCK_SIZE)
-LOCAL_LABEL(skip_16):
-#    else
 	movhs	r2, r3
-	subhs	ip, ip, #(16 * BLOCK_SIZE)
-#    endif
+	subhs	ip, ip, #(16 * 12)
 
-	lsrs	r3, r2, #8
+	lsr	r3, r2, #8
 	cmp	r3, r1
-#    if __ARM_ARCH_ISA_THUMB == 1
-	blo LOCAL_LABEL(skip_8)
-	movs r2, r3
-	subs r0, r0, #(8 * BLOCK_SIZE)
-LOCAL_LABEL(skip_8):
-#    else
 	movhs	r2, r3
-	subhs	ip, ip, #(8 * BLOCK_SIZE)
-#    endif
+	subhs	ip, ip, #(8 * 12)
 
-	lsrs	r3, r2, #4
+	lsr	r3, r2, #4
 	cmp	r3, r1
-#    if __ARM_ARCH_ISA_THUMB == 1
-	blo LOCAL_LABEL(skip_4)
-	movs r2, r3
-	subs r0, r0, #(4 * BLOCK_SIZE)
-LOCAL_LABEL(skip_4):
-#    else
 	movhs	r2, r3
-	subhs	ip, #(4 * BLOCK_SIZE)
-#    endif
+	subhs	ip, #(4 * 12)
 
-	lsrs	r3, r2, #2
+	lsr	r3, r2, #2
 	cmp	r3, r1
-#    if __ARM_ARCH_ISA_THUMB == 1
-	blo LOCAL_LABEL(skip_2)
-	movs r2, r3
-	subs r0, r0, #(2 * BLOCK_SIZE)
-LOCAL_LABEL(skip_2):
-#    else
 	movhs	r2, r3
-	subhs	ip, ip, #(2 * BLOCK_SIZE)
-#    endif
+	subhs	ip, ip, #(2 * 12)
 
 	/* Last block, no need to update r2 or r3. */
-#    if __ARM_ARCH_ISA_THUMB == 1
-	lsrs r3, r2, #1
-	cmp r3, r1
-	blo LOCAL_LABEL(skip_1)
-	subs r0, r0, #(1 * BLOCK_SIZE)
-LOCAL_LABEL(skip_1):
-	movs r2, r0
-	mov r0, ip
-	movs r3, #0
-	JMP (r2)
-
-#    else
 	cmp	r1, r2, lsr #1
-	subls	ip, ip, #(1 * BLOCK_SIZE)
+	subls	ip, ip, #(1 * 12)
 
-	movs	r3, #0
+	mov	r3, #0
 
 	JMP(ip)
-#    endif
-#  endif /* __ARM_FEATURE_CLZ */
-
+#  endif
 
 #define	IMM	#
-	/* due to the range limit of branch in Thumb1, we have to place the
-		 block closer */
-LOCAL_LABEL(divby0):
-	movs	r0, #0
-#      if defined(__ARM_EABI__)
-	bl	__aeabi_idiv0 // due to relocation limit, can't use b.
-#      endif
-	JMP(lr)
-
-
-#if __ARM_ARCH_ISA_THUMB == 1
-#define block(shift)                                                           \
-	lsls r2, r1, IMM shift;                                                      \
-	cmp r0, r2;                                                                  \
-	blo LOCAL_LABEL(block_skip_##shift);                                         \
-	subs r0, r0, r2;                                                             \
-	LOCAL_LABEL(block_skip_##shift) :;                                           \
-	adcs r3, r3 /* same as ((r3 << 1) | Carry). Carry is set if r0 >= r2. */
-
-	/* TODO: if current location counter is not not word aligned, we don't
-		 need the .p2align and nop */
-	/* Label div0block must be word-aligned. First align block 31 */
-	.p2align 2
-	nop /* Padding to align div0block as 31 blocks = 310 bytes */
 
-#else
 #define block(shift)                                                           \
 	cmp	r0, r1, lsl IMM shift;                                         \
 	ITT(hs);                                                               \
 	WIDE(addhs)	r3, r3, IMM (1 << shift);                              \
 	WIDE(subhs)	r0, r0, r1, lsl IMM shift
-#endif
 
 	block(31)
 	block(30)
@@ -252,6 +159,14 @@ LOCAL_LABEL(div0block):
 	JMP(lr)
 #endif /* __ARM_ARCH_EXT_IDIV__ */
 
+LOCAL_LABEL(divby0):
+	mov	r0, #0
+#ifdef __ARM_EABI__
+	b	__aeabi_idiv0
+#else
+	JMP(lr)
+#endif
+
 END_COMPILERRT_FUNCTION(__udivsi3)
 
 NO_EXEC_STACK_DIRECTIVE