diff options
| author | Stephen Canon <scanon@apple.com> | 2010-07-03 01:00:49 +0000 |
|---|---|---|
| committer | Stephen Canon <scanon@apple.com> | 2010-07-03 01:00:49 +0000 |
| commit | fe22a3f1e1abddc4a512aa8f9bed64b3ada78094 (patch) | |
| tree | ce6db5f8ae533b0e9c6a7bf77d66ec5b263dc3a9 /lib/arm | |
| parent | b6d4e2e3a87eb3c9a6dec0ad21d4c1dec545c137 (diff) | |
| download | compiler-rt-fe22a3f1e1abddc4a512aa8f9bed64b3ada78094.tar.gz | |
Marginally smaller implementations of bswap for ARMv4, ARMv5 that avoid the need to establish a frame
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@107555 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/arm')
| -rw-r--r-- | lib/arm/bswapdi2.S | 43 | ||||
| -rw-r--r-- | lib/arm/bswapsi2.S | 15 |
2 files changed, 26 insertions, 32 deletions
diff --git a/lib/arm/bswapdi2.S b/lib/arm/bswapdi2.S index d5d65d772..19311caad 100644 --- a/lib/arm/bswapdi2.S +++ b/lib/arm/bswapdi2.S @@ -1,4 +1,4 @@ -//===------- bswapdi2 - Implement bswapdi2 ---------------------------------===// +//===------- bswapdi2 - Implement bswapdi2 --------------------------------===// // // The LLVM Compiler Infrastructure // @@ -14,30 +14,25 @@ // // Reverse all the bytes in a 64-bit integer. // - .align 2 + .align 2 DEFINE_COMPILERRT_FUNCTION(__bswapdi2) #if __ARM_ARCH_5TEJ__ || __ARM_ARCH_4T__ - // before armv6 does not have "rev" instruction - stmfd sp!, {r7, lr} - mov r7, sp - mov r2, #255, 24 - and r3, r2, r1, lsr #8 - mov r12, #255, 16 - and lr, r12, r1, lsl #8 - orr r3, r3, r1, lsr #24 - orr r1, lr, r1, lsl #24 - and r2, r2, r0, lsr #8 - orr r3, r1, r3 - orr r1, r2, r0, lsr #24 - and r2, r12, r0, lsl #8 - orr r0, r2, r0, lsl #24 - orr r1, r0, r1 - mov r0, r3 - ldmfd sp!, {r7, pc} + mov r12, #0xff00 + + and r3, r12, r0, lsr #8 + and r2, r12, r0 + orr r3, r3, r0, lsr #24 + orr r3, r3, r0, lsl #24 + orr r2, r3, r2, lsl #8 // r2 = rev(r0) + + and r3, r12, r1, lsr #8 + and r0, r12, r1 + orr r3, r3, r1, lsr #24 + orr r3, r3, r1, lsl #24 + orr r0, r3, r0, lsl #8 // r0 = rev(r1) #else - rev r2, r1 // reverse bytes in high 32-bits into temp2 - rev r3, r0 // reverse bytes in low 32-bit into temp3 - mov r0, r2 // set low 32-bits of result to temp2 - mov r1, r3 // set high 32-bits of result to temp3 - bx lr + rev r2, r0 // r2 = rev(r0) + rev r0, r1 // r0 = rev(r1) #endif + mov r1, r2 // r1 = r2 = rev(r0) + bx lr diff --git a/lib/arm/bswapsi2.S b/lib/arm/bswapsi2.S index 309b202c0..7e3ab7f48 100644 --- a/lib/arm/bswapsi2.S +++ b/lib/arm/bswapsi2.S @@ -1,4 +1,4 @@ -//===------- bswapsi2 - Implement bswapsi2 ---------------------------------===// +//===------- bswapsi2 - Implement bswapsi2 --------------------------------===// // // The LLVM Compiler Infrastructure // @@ -18,13 +18,12 @@ DEFINE_COMPILERRT_FUNCTION(__bswapsi2) #if __ARM_ARCH_5TEJ__ || __ARM_ARCH_4T__ // before armv6 does not have "rev" instruction - mov r1, #255, 24 - mov r2, #255, 16 - and r1, r1, r0, lsr #8 - and r2, r2, r0, lsl #8 - orr r1, r1, r0, lsr #24 - orr r0, r2, r0, lsl #24 - orr r0, r0, r1 + mov r1, #0xff00 + and r2, r1, r0, lsr #8 + and r1, r1, r0 + orr r2, r2, r0, lsr #24 + orr r2, r2, r0, lsl #24 + orr r0, r2, r1, lsl #8 #else rev r0, r0 // reverse bytes in parameter and put into result register #endif |