From 6b632bbe37d6728ec2a7a7468ffad6e058642b66 Mon Sep 17 00:00:00 2001 From: Lioncash Date: Thu, 18 Dec 2014 14:25:07 -0500 Subject: [PATCH 1/2] armemu: More concise names for USAT16-related variables --- src/core/arm/interpreter/armemu.cpp | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/src/core/arm/interpreter/armemu.cpp b/src/core/arm/interpreter/armemu.cpp index b9ac8b9ad..ae865aa72 100644 --- a/src/core/arm/interpreter/armemu.cpp +++ b/src/core/arm/interpreter/armemu.cpp @@ -6192,18 +6192,22 @@ L_stm_s_takeabort: //ichfly //USAT16 { - u8 tar = BITS(12, 15); - u8 src = BITS(0, 3); - u8 val = BITS(16, 19); - s16 a1 = (state->Reg[src]); - s16 a2 = (state->Reg[src] >> 0x10); - s16 max = 0xFFFF >> (16 - val); - if (max < a1) a1 = max; - if (max < a2) a2 = max; - u32 temp2 = ((u32)(a2)) << 0x10; - state->Reg[tar] = (a1 & 0xFFFF) | (temp2); + const u8 rd_idx = BITS(12, 15); + const u8 rn_idx = BITS(0, 3); + const u8 num_bits = BITS(16, 19); + const s16 max = 0xFFFF >> (16 - num_bits); + s16 rn_lo = (state->Reg[rn_idx]); + s16 rn_hi = (state->Reg[rn_idx] >> 16); + + if (max < rn_lo) + rn_lo = max; + if (max < rn_hi) + rn_hi = max; + + state->Reg[rd_idx] = (rn_lo & 0xFFFF) | (rn_hi); + return 1; } - return 1; + default: break; } From e683f654ce2b143fb34c3a36d889d08af310db9c Mon Sep 17 00:00:00 2001 From: Lioncash Date: Thu, 18 Dec 2014 16:50:41 -0500 Subject: [PATCH 2/2] armemu: Fix lower-bounds clamping for USAT16 --- src/core/arm/interpreter/armemu.cpp | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/src/core/arm/interpreter/armemu.cpp b/src/core/arm/interpreter/armemu.cpp index ae865aa72..99fc6c45d 100644 --- a/src/core/arm/interpreter/armemu.cpp +++ b/src/core/arm/interpreter/armemu.cpp @@ -6201,10 +6201,15 @@ L_stm_s_takeabort: if (max < rn_lo) rn_lo = max; + else if (rn_lo < 0) + rn_lo = 0; + if (max < rn_hi) rn_hi = max; + else if (rn_hi < 0) + rn_hi = 0; - state->Reg[rd_idx] = (rn_lo & 0xFFFF) | (rn_hi); + state->Reg[rd_idx] = (rn_lo & 0xFFFF) | ((rn_hi << 16) & 0xFFFF); return 1; }